HomeMy WebLinkAbout07-11-2011_Council Workshop Packet
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CALL TO ORDER / PLEDGE OF ALLEGIANCE/ROLL CALL
APPROVAL OF THE AGENDA
WORKSHOP ITEMS ~ NO FINAL ACTION WILL BE TAKEN
1. (10 min) 67th Avenue Retaining Wall ATTACHMENT A
2. (5 min) Water System Comprehensive Plan Review ATTACHMENT B
3. (5 min) Oosterwyck ROW Dedication ATTACHMENT C
4. (5 min) COA Water Supply Plan ATTACHMENT D
5. (5 min) Dedication Plaque for the WWTP Upgrade & Expansion Project ATTACHMENT E
6. (10 min) FEMA Floodplain Regulations ATTACHMENT F
7. (10 min) First Amendment to Interlocal Agreement for Lobbying Services ATTACHMENT G
8. (10 min) Review of the Park Naming Policy ATTACHMENT H
9. Miscellaneous Council items
ADJOURNMENT
To download all attachments, click here
Arlington City Council Workshop
July 11, 2011 – 7 PM
City Council Chambers ~ 110 E. Third
City of Arlington
Council Agenda Bill
AGENDA ITEM:
ATTACHMENT A
COUNCIL WORKSHOP DATE:
July 11, 2011
SUBJECT: 67th Avenue Retaining wall
Discussion
DEPARTMENT OF ORIGIN:
Public Works – Jim Kelly
ATTACHMENTS:
• No attachments
EXPENDITURES REQUESTED: $ 0
BUDGET CATEGORY: N/A
LEGAL REVIEW: N/A
DESCRIPTION: Continued discussion on selection of retaining wall block (style, color, texture,
etc) for 67th Ave Phase 3 project.
HISTORY: The City has been engaged in the design of upgrades and improvements to the
third phase of the 67th Ave Rehabilitation Project. As part of the rehabilitation project, the
retaining wall on the east side of the road has to be replaced and, in some areas, increased in
size.
The preferred option, as discussed with Council at an earlier meeting, was to move forward
with a segmental retaining wall system. The proposed current retaining wall has several
options to make it less industrial looking and more visually attractive as part of a Down Town
Corridor.
This is a continuing discussion with Council for their preferred color and style of retaining wall
system they would like to have installed along 67th Ave, Phase 3.
ALTERNATIVES:
Defer to staff for additional design/planning.
RECOMMENDED ACTION:
No action requested – discussion only.
City of Arlington
Council Agenda Bill
AGENDA ITEM:
ATTACHMENT B
COUNCIL WORKSHOP DATE:
July 11, 2011
SUBJECT:
Water Comprehensive Plan Public Hearing
DEPARTMENT OF ORIGIN:
PW-Utilities
ATTACHMENTS:
N/A – Presentation Only
EXPENDITURES REQUESTED: None
BUDGET CATEGORY: N/A
LEGAL REVIEW: Pending
DESCRIPTION: Request for a Public Hearing on August 1, 2011 to present Department
of Health comments and changes made to the Arlington Water System Comprehensive
Plan.
HISTORY: As required by WAC 246-290-100, the City of Arlington updated its Water
Comprehensive Plan (Plan). The Plan details how the City will safely and efficiently
operate and maintain the water system for the next six years (2010-2016). The Plan also
includes a six year financial analysis of the Water Utility that examines the projected
revenues and expenses required for the implementation of the Plan.
A copy of the draft plan will be provided to the Department of Health for their review
and comment. After several meetings with our consultant and DOH, the City has made
some changes to the Plan to address DOH comments. The revised Plan is ready for a
Public Hearing on August 1, 2011 and subsequent adoption buy City Council. A copy
of the draft plan will on the City website and at City Hall for Public review.
ALTERNATIVES:
N/A
RECOMMENDED ACTION:
N/A
City of Arlington
Council Agenda Bill
AGENDA ITEM:
ATTACHMENT C
COUNCIL WORKSHOP DATE:
July 11, 2011
SUBJECT: Oosterwyk Right of Way Dedication DEPARTMENT OF ORIGIN:
Public Works – Utilities Division
James Kelly
ATTACHMENTS:
• Exhibit Map
EXPENDITURES REQUESTED: N/A
BUDGET CATEGORY: N/A
LEGAL REVIEW: City Attorney will prepare the dedication
documents upon Council Approval
DESCRIPTION: Staff will review the proposed right of way dedication for approval at the July 18th
Council Meeting.
HISTORY: As a condition of development for the Oosterwyk Chiropractic Office and the adjacent
Espresso stand the owner was required to dedicate the property as shown on the attached Exhibit Map
for right of way.
The project is complete and Staff will be recommended the acceptance of this dedication at the July 18th
Council Meeting.
ALTERNATIVES:
- No Action at this time
RECOMMENDED ACTION:
No Action at this time
W Division St
N West Ave
N West Ave
W Division St
"Scale:
Date:
File Name:
Cartographer:
Oo sterwyk_R OWded_11.mxd
7/1/2011 lb
Exhibit :N West Ave & Div ision St ROW Dedication
City of Arlington
1 inch = 50 fee t
Maps and GIS data are distributed “AS-IS”without warranties of any kind, eitherexpress or implied, including but not limitedto warranties of suitability for a particularpurpose or use. Map data are compiled froma variety of sources which may containerrors and users who rely upon theinformation do so at their own risk. Usersagree to indemnify, defend, and holdharmless the City of Arlington for any and all
Line Stripi ng
ROW Dedication Area
County Parcels
Approxi mate Edg e of Pavem ent
City ROW
County Trail R OW
Approximate Building Locatio n
Legend
Edge of Pavement & Line Striping from Drawings by Reid Midddleton, Division St.Traffic Circle Project 2008
ROW Dedication Areas
City of Arlington
Council Agenda Bill
AGENDA ITEM:
ATTACHMENT D
COUNCIL WORKSHOP DATE:
July 11, 2011
SUBJECT: Arlington Long Range Water
Supply Study
DEPARTMENT OF ORIGIN:
PW-Utilities
ATTACHMENTS:
– Brown & Caldwell Water Supply report
EXPENDITURES REQUESTED: None
BUDGET CATEGORY: N/A
LEGAL REVIEW: Pending
DESCRIPTION: A study prepared by Brown & Caldwell analyzing strategies for
securing and perfecting a long range water supply for the City of Arlington and for
needs within the Arlington Water Utility service area.
HISTORY: As required by the Growth Management Act, the City of Arlington must
assure there is adequate infrastructure and resources for planned growth. In addition,
as a requirement by the Department of Health for the Water Utility’s “Duty to Serve,
the Water Utility must have a plan on how to provide water for all existing and future
customers.
To meet the above requirements, the City contracted with Brown & Caldwell to analyze
the current water system, the current water rights, and pending water rights in order to
establish a plan of action for securing long term water supply. This document provides
a 30-year guide for Arlington’s future water supply including expansion at the water
treatment plant, Haller Well, and Airport Well.
ALTERNATIVES:
N/A
RECOMMENDED ACTION:
No action, discussion only.
Arlington Long Range Water Supply
Alternatives Feasibility Study
Prepared for
City of Arlington
April 11, 2011
iii
Final Arlington Feasibility Report.docx
Table of Contents
List of Figures ...................................................................................................................................................... v
List of Tables ...................................................................................................................................................... vi
List of Abbreviations ......................................................................................................................................... vii
1. Introduction ............................................................................................................................................. 1-1
2. Existing Water Supply Facilities Assessment ........................................................................................ 2-1
2.1 Haller Well Field ............................................................................................................................. 2-1
2.1.1 Analysis of Haller Well Field Capacity and Expansion ...................................................... 2-2
2.2 Water Treatment Plant .................................................................................................................. 2-3
2.2.1 Contact Adsorption Clarification ........................................................................................ 2-5
2.2.2 Filtration .............................................................................................................................. 2-6
2.2.3 Disinfection ......................................................................................................................... 2-7
2.2.4 Analysis of Existing WTP Capacity ................................................................................... 2-10
2.2.5 Needs and Recommendations ........................................................................................ 2-10
2.3 Airport Well Field .......................................................................................................................... 2-14
2.3.1 Analysis of Airport Well Capacity and Expansion ............................................................ 2-14
2.4 Operating Costs for Haller and Airport Well Fields ..................................................................... 2-15
2.5 Snohomish PUD Interconnection ................................................................................................ 2-16
2.5.1 Existing Operating Cost Summary ................................................................................... 2-18
2.5.2 2028 Capacity Improvements ......................................................................................... 2-18
3. Water Rights and Water Demand Summary ......................................................................................... 3-1
3.1 Water Rights ................................................................................................................................... 3-1
3.1.1 Haller Well Field Supply ..................................................................................................... 3-1
3.1.2 Airport Well Field Supply .................................................................................................... 3-2
3.2 Demand Forecast ........................................................................................................................... 3-3
3.3 Water Rights Analysis .................................................................................................................... 3-4
3.3.1 Haller Well Field Supply ..................................................................................................... 3-4
3.3.2 Airport Well Field Supply .................................................................................................... 3-5
3.4 Target Capacity Projections ........................................................................................................... 3-5
4. Regulatory Constraints and Water Quality Objectives .......................................................................... 4-1
4.1 Regulatory Overview ...................................................................................................................... 4-1
4.1.1 Federal Regulations ........................................................................................................... 4-1
4.2 Constituents of Concern to Water Purveyors ............................................................................... 4-3
4.2.1 Microbiological Water Quality ............................................................................................ 4-3
4.2.1.1 Coliform Bacteria ........................................................................................................ 4-3
4.2.1.2 Giardia and Viruses .................................................................................................... 4-4
4.2.1.3 Cryptosporidium ......................................................................................................... 4-4
4.2.1.4 Turbidity....................................................................................................................... 4-6
Arlington Long Range Water Supply Alternatives Feasibility Study Table of Contents
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Final Arlington Feasibility Report.docx
4.2.2 Disinfectants and Disinfection By-Products ..................................................................... 4-6
4.2.3 Chemical Contaminants ..................................................................................................... 4-7
4.2.4 Emerging Contaminants .................................................................................................... 4-7
4.2.4.1 Possible Future Regulatory Scenarios ...................................................................... 4-8
4.3 Raw and Finished Water Quality ................................................................................................... 4-9
4.3.1 Primary Inorganic Compounds .......................................................................................... 4-9
4.3.2 Secondary and Physical Standards ................................................................................. 4-11
4.3.3 Disinfection By-Products .................................................................................................. 4-13
4.4 Regulatory Scenarios and Their Implications ............................................................................. 4-14
5. Facilities Evaluation ................................................................................................................................ 5-1
5.1 Overview of Business Case Evaluation Process ........................................................................... 5-1
5.2 Selection of Expert Panel ............................................................................................................... 5-2
5.3 BCE Workshop 1 ............................................................................................................................ 5-3
5.3.1 Determine Level of Service ................................................................................................ 5-3
5.3.2 Brainstorm Alternatives and Initial Screening .................................................................. 5-4
5.3.3 Risk Discussion .................................................................................................................. 5-7
5.4 BCE Workshop 2 Preparation ........................................................................................................ 5-7
5.5 BCE Workshop 2 and Evaluation of Final Alternatives .............................................................. 5-10
5.5.1 Environmental Risks and Opportunities of Water Supply Alternatives ......................... 5-10
5.5.2 Life-Cycle Costs of Discrete Alternatives ......................................................................... 5-11
5.5.3 Life-Cycle Costs for Combinations of Discrete Alternatives ........................................... 5-13
5.6 Recommended Plan ..................................................................................................................... 5-15
References ......................................................................................................................................................... 1
Appendix A: Assessment of Water Supply Alternatives ................................................................................... A
Appendix B: Disinfection Profiling and Benchmarking Guidance Manual ...................................................... B
Appendix C: Analysis of Precipitate .................................................................................................................. C
Appendix D: Summary of Federal and State Water Quality Regulations ........................................................ D
Appendix E: Workshop 1 Meeting Notes ...........................................................................................................E
Appendix F: 2009 Water Production Cost Estimate ......................................................................................... F
Arlington Long Range Water Supply Alternatives Feasibility Study Table of Contents
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Final Arlington Feasibility Report.docx
List of Figures
Figure 2-1. One of three Haller Park wells ..................................................................................................... 2-2
Figure 2-2. WTP process flow diagram .......................................................................................................... 2-4
Figure 2-3. Pre-chlorination equipment ......................................................................................................... 2-8
Figure 2-4. Sodium hypochlorite equipment: post-filtration disinfection .................................................... 2-8
Figure 2-5. Caustic storage system ............................................................................................................. 2-11
Figure 2-6. Caustic application point ........................................................................................................... 2-11
Figure 2-7. Brownish color in finished water sampling appurtenances .................................................... 2-12
Figure 2-8. Stained tubing ............................................................................................................................ 2-12
Figure 2-9. Finished water pipe loop ........................................................................................................... 2-13
Figure 2-10. Airport well field site location .................................................................................................. 2-14
Figure 2-11. Equipment in Airport well building .......................................................................................... 2-15
Figure 2-12. Snohomish PUD water distribution system ............................................................................ 2-17
Figure 2-13. 1,000 gpm system improvements in 2028 ........................................................................... 2-20
Figure 2-14. 3,000 gpm system improvements in 2028 ........................................................................... 2-21
Figure 3-1. Projected demand versus water right supply capacity .............................................................. 3-6
Figure 4-1. Inorganic compound concentrations in raw water .................................................................. 4-10
Figure 4-2. Secondary and physical standards in raw water ..................................................................... 4-12
Figure 4-3. Treated water turbidity at the Water Treatment Plant ............................................................. 4-13
Figure 4-4. Highest DBP concentrations in finished drinking water .......................................................... 4-14
Figure 5-1. BCE process overview .................................................................................................................. 5-2
Figure 5-2. Comparison of Haller WTP expansion alternatives .................................................................... 5-5
Figure 5-3. Recommended discrete water supply project timing .............................................................. 5-16
Arlington Long Range Water Supply Alternatives Feasibility Study Table of Contents
vi
Final Arlington Feasibility Report.docx
List of Tables
Table 2-1. Vertical Rise Rate of CAC .............................................................................................................. 2-6
Table 2-2. Filtration Design Parameters ........................................................................................................ 2-7
Table 2-3. CT Requirements for Giardia lamblia Cysts ................................................................................. 2-9
Table 2-4. Clearwell Volume as Percent of Peak Day Flow ........................................................................ 2-10
Table 2-5. 2009 Haller and Airport Well Fields Operating Costs ............................................................... 2-16
Table 2-6. Summary of 2004-2010 Snohomish PUD Water Use and Cost .............................................. 2-18
Table 2-7. PUD Improvements Needed to Maintain and Expand PUD Supply to City of Arlington .......... 2-19
Table 3-1. Haller Well Field Water Rights ...................................................................................................... 3-2
Table 3-2. Airport Well Field Water Rights ..................................................................................................... 3-3
Table 3-3. Projected Water Demands ............................................................................................................ 3-4
Table 3-4. Haller Well Field Capacity ............................................................................................................. 3-4
Table 3-5. Haller Well Field Water Right Analysis ......................................................................................... 3-5
Table 3-6. Airport Well Field Water Right Analysis ........................................................................................ 3-5
Table 3-7. Description of Water Supply Scenarios ....................................................................................... 3-6
Table 4-1. Summary of USEPA Drinking Water Quality Regulations ............................................................ 4-2
Table 4-2. USEPA LT2ESWTR Bin Assignment for Cryptosporidium Reduction Requirements a ............... 4-4
Table 4-3. USEPA LT2ESWTR Microbial Toolbox for Cryptosporidium Treatment Credits ......................... 4-5
Table 4-4. USEPA Stage 1/2 D/DBP Rules Disinfectants and Disinfection By-Product Limits .................. 4-6
Table 4-5. Stage 2 Disinfectants and Disinfection By-Products Rule Compliance Schedule
for Systems Serving 10,000 to 49,999 people ...................................................................................... 4-7
Table 4-6. USEPA UCMR 2 Monitoring List .................................................................................................... 4-8
Table 5-1. Discrete Water Supply Alternatives .............................................................................................. 5-5
Table 5.2. Potential Risks with Water Supply Alternatives ........................................................................... 5-7
Table 5-3. Capital Cost Estimating Markups ................................................................................................. 5-8
Table 5-4. Distribution of Capital Costs ......................................................................................................... 5-8
Table 5-5. 2009 Water Use Profilea ............................................................................................................... 5-9
Table 5-6. Operations and Maintenance Cost Assumptions ........................................................................ 5-9
Table 5-7. Analysis of Potential Risks of Water Supply Alternatives.......................................................... 5-11
Table 5-8. 20 Year Life-Cycle Cost Analysis for Discrete Water Supply Alternatives ................................ 5-12
Table 5-9. 20 Year Life-Cycle Cost Analysis for Combinations of Discrete Water Supply Alternatives .... 5-14
Table 5-10. Recommend Water Supply Plan .............................................................................................. 5-17
Arlington Long Range Water Supply Alternatives Feasibility Study Table of Contents
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Final Arlington Feasibility Report.docx
List of Abbreviations
μg/L microgram(s) per liter
ADD average day demand
BCE business case evaluation
CAC contact adsorption clarification
ccf 100 cubic feet
CCL Contaminant Candidate List
City City of Arlington
CT concentration and time
DBP disinfection by-product
D/DBPR Stage 2 Disinfectants/Disinfection By-
Products Rule
DOH Washington State Department of Health
DSL distribution system leakage
EDC endocrine disrupting compound
ENR Engineering News-Record
gpcd gallons per capita per day
gpd gallon(s) per day
gpm gallon(s) per minute
gpm/sf gallons per minute per square foot
HAA5 five haloacetic acids
hp horsepower
ICR Information Collection Rule
IDSE Initial Distribution System Evaluation
IESWTR Interim Enhanced Surface Water Treatment
Rule
LOS level of service
LRAA locational running annual average (LRAA)
LT1ESWTR Long Term 1 Enhanced Surface Water
Treatment Rule
LT2ESWTR Long Term 2 Enhanced Surface Water
Treatment Rule
MCC motor control center
MCL maximum contaminant level
MDD maximum day demand
MG million gallon(s)
mg/L milligram(s) per liter
MnO2 manganese dioxide
MRDL maximum residual disinfectant level
NPV net present value
NTU nephelometric turbidity unit
O&M operations and maintenance
PAC polyaluminum chloride
PHD peak hour demand
PPCP pharmaceuticals and personal care products
PSPL Puget Sound Power and Light Company
PUD Public Utility District
PWS public water system
PWTF Public Works Trust Fund
scfm standard cubic feet per minute (scfm)
SDWA Safe Drinking Water Act
SWTR Surface Water Treatment Rule
TOC total organic carbon
TTHM total trihalomethanes
UCMR Unregulated Contaminant Monitoring Rule
UFRV unit filter run volume
UFWV unit filter-to-waste volume
USEPA U.S. Environmental Protection Agency
UWBV unit backwash volume
VFD variable-frequency drive
WSP Water System Plan
WTP water treatment plant
WUE water use efficiency
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Final Arlington Feasibility Report.docx
Section 1
Introduction
The City of Arlington (City) anticipates increased water demand and supply needs as a result of service
area population growth and development. The City faces important decisions on how to supply water to a
growing community that will affect its future growth and quality of life for years to come. The City’s goals
are to provide the highest quality water for the least cost, plan for the future and, ultimately, make the
best choices for both for the short term and for future generations.
The City currently serves a population of 17,500 (7,709 ERUs) with an average day demand (ADD) of
969 gpm and a maximum day demand (MDD) of 1,956 gpm. The City relies on the following three
primary sources of potable water to serve its customers:
Haller well field and existing surface water treatment plant (WTP): supplied from the Haller well
field intake along the Stillaguamish River; 1,500 gallon per minute (gpm), actual peak capacity
Airport groundwater well: 200-gpm, actual peak capacity
Snohomish County Public Utility District (PUD) intertie connection: currently using approximately
350 gpm of an agreement with a capacity of 1,000 gpm
The City anticipates population growth will increase ADD and MDD in 20 years to 1,852 gpm and 3,742
gpm, respectively, and in 50 years to 3,376 gpm and 6,818 gpm, respectively. To meet increased
demand, the City is considering:
expanding Haller well field and WTP capacity
increasing the capacity of the Airport well field
increasing the PUD intertie connection
This Feasibility Study is developed to evaluate these alternatives and recommend the most effective
water supply solution for the City to meet water demand forecasts. It presents detailed comparative
analyses of alternatives to provide a high-quality water supply in the most economical manner possible,
with due consideration to the following factors:
anticipated growth
the value of existing system capital assets and water rights
site space available for WTP expansion
existing and future water quality regulations
available treatment technology options and performance
operations and maintenance (O&M) needs
project costs and schedule needs
redundancy of water supply sources
stewardship of limited water resources and the environmental needs of the Stillaguamish basin
sustainability of water to supply future human and aquatic needs
Arlington Long Range Water Supply Alternatives Feasibility Study Section 1
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Final Arlington Feasibility Report.docx
To address the City’s needs, this Feasibility Study uses a collaborative approach referred to as a
“business case evaluation” (BCE) to:
Help the City assess and address the full spectrum of questions and considerations involved in
future water supply planning.
Guide appropriate capital investment and management decisions.
Develop a water supply vision for the future of Arlington and the Stillaguamish basin.
This Feasibility Study is subdivided into the following sections:
Section 1 Introduction: Section 1 provides an overview of the issues the City is facing with respect to
future water supply and an overall structure of the Feasibility Study.
Section 2 Existing Water Supply Facilities Assessment: Section 2 describes the nature of the City’s three
existing water supply sources, their physical and operating conditions, and limitations with respect to
expansion and operations.
Section 3 Water Rights and Water Demand Summary: Section 3 describes the City’s current water
rights and identifies additional potential future water rights available to the City. Water demand forecast
information to the year 2058 is also provided.
Section 4 Regulatory Constraints and Water Quality Objectives: Section 4 provides information related
to water quality goals and regulations for a variety of regulated and non-regulated water quality
constituents and compares them with current water quality data from the City’s water supply sources.
Section 5 Facilities Evaluation: Section 5 identifies and evaluates numerous water supply and treatment
alternatives using the BCE process. Life-cycle cost information is provided for select alternatives along
with a discussion of non-economic decision factors. A recommended plan of phased implementation of
discrete water supply projects is identified.
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Final Arlington Feasibility Report.docx
Section 2
Existing Water Supply Facilities
Assessment
This section summarizes the condition, capabilities, and limitations of the existing City of Arlington water
supply and treatment facilities. Assessments of the Haller well field, WTP, Airport well field, and
Snohomish County PUD intertie connection are detailed based on site inspections and field visits,
interviews and discussions with City staff, and a review of the following documentation provided by the
City:
2004 Water System Plan (WSP)
2006 Draft Supplement to 2004 WSP
2010 Draft WSP
2010 Integrated Water Resource Management Program (to be included in 2010 WSP)
WTP record drawings
2003 Comprehensive Performance Evaluation Report (Cadmus Report)
WTP Monthly Reports including supplemental disinfection by-product (DBP) and inorganic
chemical testing
Snohomish PUD 2028 CIP Analysis Final
2007 Snohomish PUD Memorandum
1998 Wholesale Water Agreement between City of Arlington and Snohomish County
2009 Water Production Cost Estimate for Haller and Airport Wells
PUD Water Purchase Rates and Costs from 2004 to 2010
2.1 Haller Well Field
The Haller well field consists of three shallow wells located in Haller Park adjacent to the Stillaguamish
River. The wells withdraw groundwater under the direct influence of surface water from the river and
provide raw water supply to the nearby City WTP. Each well is housed in a cement masonry unit building
containing mechanical and electrical equipment as illustrated in Figure 2-1.
Arlington Long Range Water Supply Alternatives Feasibility Study Section 2
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Final Arlington Feasibility Report.docx
Figure 2-1. One of three Haller Park wells
Haller well 1 was originally constructed between 1962 and 1964. It was abandoned in 2001 due to low
yields, and then relocated and reconstructed in 2002 as well 1R. Well 1R is shallow, with a depth of 36
feet and a diameter of 16 inches. Well 1R was designed with a 25 horsepower (hp), vertical-turbine
pump to deliver 570 gpm of water from the well to the WTP.
Well 1R water exhibits elevated levels of iron and manganese. While iron and manganese in well water is
generally not associated with human health concerns, presence in high concentrations can contribute to
aesthetic difficulties. Given the manganese concentrations present in the well water, the City generally
reserves well 1R as a backup emergency supply source.
Haller well 2 was constructed in 1961. It was rehabilitated in 2001 and consists of a 36-inch-diameter,
38-foot-deep well equipped with a 570 gpm, 25 hp vertical turbine pump. The well 2 building also
houses common equipment for the Haller well field, including telemetry and motor control center (MCC)
electrical equipment, and an emergency generator capable of powering well field equipment during
power outages.
Haller well 3 was part of the original water supply for the Town of Arlington in the early 1900s. Puget
Sound Power and Light used the well when it ran the water utility from 1916 to 1939. The City regained
ownership of the well, with its 1924 water right, when it purchased the utility in 1939 (refer to Section
3.1 for more details). It was rehabilitated in 1939 and again in 2001. Well 3 includes two 25 hp vertical
turbine pumps for a designed total capacity of 1,100 gpm. Well 3 serves as the primary raw water supply
source for the WTP. Well 2 is used when well 3's capacity is insufficient to meet demands.
The well pumps can be run individually or simultaneously in any combination as necessary to meet water
demand. Water is pumped from the wells to the WTP through 12-inch-diameter ductile iron and 10-inch-
diameter cast-iron piping.
2.1.1 Analysis of Haller Well Field Capacity and Expansion
Pacific Groundwater Group (PGG) evaluated the existing Haller well field capacity and the feasibility of
adding future wells. The results of the study are highlighted below. PGG’s assessment of the Arlington
well field, as well as other water supply sources, is included in Appendix A.
Wells 2 and 3 are unable to meet the target capacity of 1,710 gpm with one or both wells limiting
production. Wells 2 and 3 production is estimated to be limited to 1,500 gpm. Both wells should be
tested independently with existing pumps to assess the current specific capacity. It is anticipated that
Well 3 may need redevelopment.
Arlington Long Range Water Supply Alternatives Feasibility Study Section 2
2-3
Final Arlington Feasibility Report.docx
The interference analysis indicates that it may be possible to achieve a future expanded capacity of
2,500 gpm with one additional vertical well at the site. An assessment of dry season pumping water
levels during low river stages and high demand indicates that there may be 1.5 to 3.5 feet of available
drawdown in Wells 2 and 3. The accuracy of these measurements is significant for estimates of pumping
impacts from an additional well. It is recommended that a licensed surveyor measure the well water level
measuring points, the Stillaguamish river gage, and the pump pedestals so that pumping and static
groundwater levels and river elevations can be accurately correlated to one another. Additionally,
transducer and hand-measured water levels should be accurately tied to known measuring points.
In order to minimize interference drawdown within the well field, the new well should be sited at the
greatest distance possible from existing wells, but prospective locations are limited by the narrow extent
of the alluvial aquifer. High well efficiency may be achieved with a 24 to 30-inch diameter well and a well
completion depth of approximately 38 feet below ground surface. Before determining an additional
well’s location, it is recommended that a more accurate study of dry season pumping water levels,
interference drawdown, and aquifer extent be completed.
Future vertical wells may have manganese and possibly iron concentrations marginally below or above
secondary MCLs. It is recommended that water quality samples be collected either during the drilling of
the production well or from one or more small diameter test holes.
Given current well field constraints, it does not appear as though the City could fully utilize the well field
to a capacity over 4,000 gpm with vertical wells. However, a capacity of over 4,000 gpm could likely be
obtained with one Ranney-type collector. A Ranney-type collector consists of a large diameter casing
(approximately 16 feet) with lateral screens that would extend outward into the aquifer towards the
Stillaguamish River. The water quality of each lateral screen could be isolated and tested to minimize
potential manganese or iron exceedences of secondary MCLs. If a Ranney-type collector was installed,
the City could use their existing wells for backup supply during future maintenance events.
2.2 Water Treatment Plant
The Haller well field provides raw water supply to the WTP as discussed in Section 2.1. This section gives
an overview of the WTP and analyzes whether the existing WTP could support an increase in nominal
rated capacity from 1,710 gpm to 2,500 gpm.
A process flow diagram for the WTP is included as Figure 2-2. The WTP includes three Key-Pac Model AC
packaged treatment trains, which consist of an upflow contact adsorption clarifier followed by dual-
media rapid sand filters. Each treatment train is designed for a 570 gpm maximum capacity. The
combined nominal treatment capacity of these three treatment trains is 1,710 gpm.
Arlington Long Range Water Supply Alternatives Feasibility Study Section 2
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Figure 2-2. WTP process flow diagram
Modified from 2003 Cadmus Report
Arlington Long Range Water Supply Alternatives Feasibility Study Section 2
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Final Arlington Feasibility Report.docx
To reduce the potential for biological growth in the rapid sand filters, the raw well water supply is pre-
chlorinated using 12.5 percent strength sodium hypochlorite injection to maintain a 0.25 milligram per
liter (mg/L) free chlorine residual concentration. Following pre-chlorination, primary coagulant
(Sumaclear 700) is added and mixed into the raw water flow via a static mixer. A secondary coagulant,
Clearbrook AE3101 (a filter aid), is added just upstream of the upflow clarifiers.
Flow control for the three treatment trains is provided by Rotork actuators and flow meter control loops.
The water is sampled after the static mixer and prior to the treatment trains using a streaming current
monitor.
Following filtration, sodium hypochlorite is injected to provide chlorine disinfection in a 0.175 million
gallon (MG) clearwell. Three finished water pumps deliver flows from the clearwell to the City water
system. Sodium hydroxide solution at 25 percent strength is dosed into the finished water pump flow
and mixed via a static mixer for final pH control.
2.2.1 Contact Adsorption Clarification
The Keystone, Key-Pac Model AC, treatment trains utilize contact adsorption clarification (CAC) via an
upflow clarifier. Coagulant-dosed raw water enters the bottom of the clarifier through an array of slotted
nozzles. The CAC provides flocculation and clarification using a 42 inch deep bed of coarse media
(crushed quartz) with an effective size of 2.0 to 2.2 mm and a uniformity coefficient of 1.5. The CAC also
has a 3 inch deep gravel layer to support the media.
The upflow clarifiers are washed periodically using air scour and hydraulic wash water cycles in an
upward, forward flow direction. The upflow clarifiers are washed as needed, typically after around 20
hours of normal operation. The washes are initiated based on elapsed runtime, and not head loss
accumulation. A typical head loss observed during upflow clarifier operation is 18 inches of water (at
430 gpm).
When the upflow clarifiers are due to be washed, the backwash water to waste valve opens and the filter
effluent valve closes. Air scour is initiated for 5 minutes at 260 standard cubic feet per minute (scfm).
During the air scour cycle, wash water flow rate (as supplied from the Haller well field raw water pumps)
increases gradually to 580 gpm. The wash cycle operates for 21 minutes (1,260 seconds). Following the
wash cycle, the treatment train shuts down for 4 minutes to allow the launders to be manually hosed out
and the launder walls cleaned with a brush. The entire treatment train is then filtered-to-waste for
approximately 10 minutes before normal filtration operations resume.
The CAC process was analyzed to determine if it could support an increase from the nominal rated
capacity of 1,710 gpm to 2,500 gpm. For an upflow clarifier, the vertical rise rate becomes the
controlling criterion; the flow rise must be less than the respective floc settling rate. The vertical rise rate
was calculated based on the CAC flow rate, filter productivity, and clarifier area as shown in Table 2-1.
Overall filter productivity is factored in the vertical rise rate calculation to account for the difference
between raw water feed to the plant and water pumped to the distribution system. The quantity of water
being wasted during backwashing is added to the treatment process throughput to account for this
amount of added flow that must be processed to deliver a set plant finished water capacity. As a result,
the inflow to the CAC system is slightly greater than 1,710 gpm during peak flow conditions.
At a peak day flow rate of 1,710 gpm, the vertical rise rate for the CAC process is calculated to be 9.25
gallons per minute per square foot (gpm/sf). For this type of clarifier, a maximum vertical rise rate of
approximately 10 gpm/sf is typical (Cadmus, 2003). At a potential future peak plant flow rate of 2,500
gpm, the calculated vertical rise rate would be 13.5 gpm/sf — a value exceeding the maximum
recommended vertical rise rate for this system. Therefore, flocculation and clarification capacity would
need to be expanded to achieve expansion to a future 2,500 gpm WTP flow rate capacity. At a vertical
rise rate of approximately 10 gpm/sf, the CAC has a limited capacity of 1,835 gpm.
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Velocity gradients are another important consideration for the upflow clarifiers and can have a significant
effect on flocculation. If velocity gradients are too low, the particles will not form a floc. If the gradient is
too high the floc can be sheared. Based on the root mean velocity gradient calculated, the floc would be
sheared in the existing upflow clarifiers at 2,500 gpm. The floc shearing concern emphasizes the
conclusion that the existing upflow clarifiers operate at near full capacity, the 1,710 gpm nameplate
capacity of the Keystone treatment trains.
Table 2-1. Vertical Rise Rate of CAC
Existing Condition Expansion Scenario
Flow rate (gpm)
Minimum 411 600
Annual average 769 1,125
Peak day 1,710 2,500
Clarifier area (sf) 64 64
No. of CAC basins 3 3
Filter productivity (%) 96.3 97.4
Vertical rise rate (gpm/sf)
Minimum 2.22 3.21
Annual average 4.16 6.01
Peak day 9.25 13.37
2.2.2 Filtration
Water from each upflow clarifier flows into distribution troughs to feed pairs of dual-media filters
operated in parallel within each Keystone treatment train. The filters consist of 18 inches of anthracite
with an effective size of 1.0 mm, a 12-inch sand layer with an effective size of 0.5 mm, another 6-inch
sand layer with an effective size of 1.0 mm, and 3 inches of support gravel.
Filtered water is collected through nozzles at the base of each filter unit and transported in a common
header to supply the WTP clearwell. Filtered water turbidity is measured using Hach 1720 D
turbidimeters, which sample the filtered water effluent from each pair of parallel filters. The timing of
filter backwashes depends on raw water turbidity, flow, and operator judgment. Typical filter fun times
are as short as 16 hours and as long as 40 hours.
Each of the two filters in each treatment train is backwashed sequentially. Filter backwash water supply
comes from the clearwell via two 25 hp vertical turbine pumps operating in alternating service and each
capable of delivering 1,000 gpm peak backwash flow. During backwash, the raw water valves close and
the filter water level is drained down to approximately 11 inches above the filter media (ranges from 6 to
12 inches). An air scour cycle operates for 1 minute and the WTP backwash pumps supply low flow wash
water to the filter until the water rises to approximately 25 inches above the filter media. The filter is next
allowed to settle for 5 minutes, after which the filter is backwashed for 7 minutes with high flow wash
water (1,000 gpm or 16.7 gpm/sf). Following backwash, the filter is again allowed to settle for 5
minutes. This procedure is then repeated for the second filter in the treatment train. Following
backwashing of both filters in the treatment train, the filters are operated in a filter-to-waste mode for up
to 50 minutes.
During backwash, it is important to fully expand and fluidize the filter media to effectively remove
particles and achieve effective filter media cleansing. Approximately 25–35 percent filter bed expansion
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during backwash is generally desirable for effective cleaning. Filter bed expansion of only approximately
10 percent was observed during filter backwashing at Arlington. During backwash, the distance from the
bottom of the wash water trough to the top of the expanded media bed was observed at approximately
27 inches. Typically, a distance of only 18 inches is recommended to avoid media loss during backwash.
It is recommended that WTP backwash cycles be adjusted to increase bed expansion during backwash
given the available clearance and potential to help lengthen filter runs.
The filters have a ratio of depth to effective size (L/d ratio) of 1,000. A typical design criterion is for an
L/d ratio of 1,000 to 2,000. The filter L/d ratios are in the acceptable range, but at the low end. To
increase the L/d ratio, additional filter media could likely be added to the filters without risking loss of
filter media during backwash.
The filters were evaluated at peak day flow rates for existing and potential expansion scenario conditions
as shown in Table 2-2. The maximum design hydraulic loading rate for these filters is 4.75 gpm/sf (KEY-
PAC). Typically, a standard dual-media filter can accommodate filtration loading rates up to 6 gpm/sf.
Filtration systems can operate at higher filtration loading rates if systems can demonstrate consistent 2
log Giardia lamblia cysts removal and 2 log cryptosporidium oocysts removal while not exceeding a
filtered turbidity of 0.3 nephelometric turbidity units (NTU) for 95 percent of samples taking each month.
The existing filter operating conditions at 1,710 gpm satisfy the 6 gpm/sf criteria. Under a 2,500 gpm
expansion scenario, filtration capacity will either need to be increased or the filters tested to
demonstrate treatment criteria performance at higher filtration loading rates.
Table 2-2. Filtration Design Parameters
Existing Condition Expansion Scenario
Peak day flow rate (gpm) 1,710 2,500
Filter area (sf) 120 120
Anthracite depth (inches) 18 18
Sand depth (inches) 12.00 12.00
L/D 1,067 1,067
Hydraulic loading rate (gpm/sf)
All filters online 4.9 7.1
One filter offline for backwash 7.4 10.7
UFRV (gpm/sf-run) 10,361 14,970
Water recovery is evaluated though unit filter run volume (UFRV), unit backwash volume (UWBV), and
unit filter-to-waste volume (UFWV). Filters should be designed and operated for a recovery of at least 95
percent. The existing filters have a recovery rate of 96.3 percent. When the upflow clarifiers and the
water used to wash them are taken into account, the total recovery rate for the treatment trains is 94
percent.
2.2.3 Disinfection
Sodium hypochlorite is used for pre-filtration and post-filtration disinfection at the WTP. Pre-filtration
chlorination is used to reduce microbial growth in the filters. The pre-filtration chlorine dosage is
manually adjusted to maintain a 0.25 mg/L chlorine residual upstream of the raw water static mixer. An
image of the pre-filtration chlorination equipment is shown in Figure 2-3.
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Figure 2-3. Pre-chlorination equipment
For post-filtration disinfection, the WTP typically doses sodium hypochlorite at 1 mg/L. The sodium
hypochlorite generation room is shown in Figure 2-4. It includes a 500-gallon tank and two sodium
hypochlorite metering pumps.
Figure 2-4. Sodium hypochlorite equipment: post-filtration disinfection
The WTP is required to achieve 3-log inactivation of Giardia lamblia cysts, 4-log inactivation of viruses,
and 2-log inactivation of cryptosporidium oocysts. Under current regulations, the WTP is granted removal
credits for the direct filtration process: 2-log credit for Giardia lamblia cysts, 2-log credit for
cryptosporidium, and a 1-log credit for viruses. Thus, disinfection and clearwell disinfection contact time
must be sufficient to provide 1-log Giardia lamblia cyst inactivation and 3-log virus inactivation.
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Currently, the WTP tabulates log removal credits only for post-filtration disinfection and therefore, only
post-filtration disinfection is considered in analysis of clearwell disinfection capacity.
Inactivation is achieved by meeting specified disinfectant concentration and time (CT) requirements
specified in the U.S. Environmental Protection Agency (USEPA) Guidance Manual on Disinfection Profiling
and Benchmarking (USEPA 1999) included in Appendix B. CT is determined by multiplying the
disinfectant concentration (mg/L by the amount of time (minutes) that the water is in contact with the
disinfectant. The CT for the clearwell was calculated using a baffling factor of 0.5 and a pH of 7.0. The
City also applies a baffling factor of 0.5 in its Surface Water Treatment Rule (SWTR) Disinfection Monthly
Report. According to 2007 to 2010 operational data, the maximum pH of the filtered water prior to
disinfection was 7.1.
The clearwell has design minimum and maximum water depths of 7.5 feet and 9.8 feet, respectively.
Based on the City’s SWTR Disinfection Monthly Report, an active volume of 0.140 MG at the minimum
water surface level and 0.175 MG at the maximum water surface level is used for the CT calculations. CT
requirements for Giardia lamblia cysts are shown in Table 2-3 for design and expansion scenario flow
conditions, at minimum and maximum water surface elevations. Minimum winter and summer
temperature conditions were chosen to determine the maximum required inactivation for Giardia lamblia
cysts. Required virus inactivation is also achieved for each of the CT values presented in Table 2-3.
Table 2-3. CT Requirements for Giardia lamblia Cysts
Se
a
s
o
n
Fl
o
w
Co
n
d
i
t
i
o
n
1
Fl
o
w
(
g
p
m
)
Cl
e
a
r
w
e
l
l
De
p
t
h
(
f
t
)
Re
s
i
d
u
a
l
C
l
2
(m
g
/
L
)
Ti
m
e
(
m
i
n
)
pH
Te
m
p
(
°
C
)
CT
90
a
CT
c
a
l
c
In
a
c
t
i
v
a
t
i
o
n
Ra
t
i
o
Su
f
f
i
c
i
e
n
t
Cl
e
a
r
w
e
l
l
Vo
l
u
m
e
?
Winter Design average day 769 7.5 1.0 87 7.0 5 50 87 1.82 Yes
Winter Design average day 769 9.8 1.0 114 7.0 5 50 114 2.27 Yes
Summer Design maximum day 1,710 7.5 1.0 39 7.0 15 25 39 1.64 Yes
Summer Design maximum day 1,710 9.8 1.0 49 7.0 15 25 49 1.95 Yes
Winter
Expansion scenario
average day 1,125 7.5 1.0 60 7.0 5 50 60 1.24 Yes
Winter
Expansion scenario
average day 1,125 9.8 1.0 78 7.0 5 50 78 1.56 Yes
Summer
Expansion scenario
maximum day 2,500 7.5 1.0 27 7.0 15 25 27 1.12 Yes
Summer
Expansion Scenario
maximum day 2,500 9.8 1.0 35 7.0 15 25 35 1.40 Yes
a. CT90 represents the CT requirement for an additional 1 log removal on top of the 2-log credit for direct filtration for Giardia lamblia
cysts.
The existing clearwell provides sufficient CT volume for all of the conditions shown in Table 2-3. If the pH
increased to 7.5, then the residual chlorine concentration would need to be increased from 1.0 to
1.2 mg/L to meet the required CT at 15ºC.
Additional considerations in clearwell sizing are based on operational constraints. Generally, a nominal
clearwell volume of 5 to 10 percent of total peak day finished water flow is considered desirable. At the
expansion condition peak day flow of 2,500 gpm, the existing clearwell volume is 3.7 percent and 4.9
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percent at minimum and maximum water surface elevations, respectively (as shown in Table 2-4).
Therefore, it may be desirable to increase the clearwell volume to accommodate future flows.
Table 2-4. Clearwell Volume as Percent of Peak Day Flow
Design Flow = 1,700 gpm Expansion Scenario Flow = 2,500 gpm
Minimum depth 5.4% 3.7%
Maximum depth 7.1% 4.9%
2.2.4 Analysis of Existing WTP Capacity
From data collected during the examination of the existing plant and a comparison to nominal design
criteria for analogous treatment processes, an estimate of the ultimate plant capacity can be
determined. The capacity limiting process at the existing WTP is the CAC process described in Section
2.2.1. Based on the size of the existing CAC system, a maximum hydraulic loading rate of 10 gpm/sf,
and consideration of the amount of water needed to wash the CAC system, the maximum possible peak
net capacity of the CAC system (and hence the entire plant) is estimated to be approximately 1,835 gpm.
2.2.5 Needs and Recommendations
The existing WTP facilities were constructed in 1999 as a part of the Water Treatment Plant/Haller Park
Well Field Improvements. In general, the facility and major unit process equipment are in good condition.
This section discusses a few deficiencies and concerns identified during the evaluation of the existing
WTP facilities.
CAC System. There are a few areas of concern and potential deficiencies in the existing CAC system. The
clarifier underdrains appear to do a poor job of providing uniform air scour and backwash water
distribution, as evidenced by uneven media deposition. This shortcoming cannot likely be easily
corrected. Additionally, during CAC wash cycles, some of the wash water flows toward the filtrations
units. As a result, each treatment train is shut down for 4 minutes and filtered to waste for 10 minutes
after a CAC wash cycle. To alleviate this shortcoming and allow the downtime during CAC wash cycles to
be reduced, installation of a motor-operated weir gate or other such similar device between the CAC tank
and the filters is recommended. The gate would be configured to close during a CAC wash cycle to
prevent waste wash water from flowing onto the filters.
Flocculation and clarification capacity would need to be expanded to achieve expansion to a future
2,500 gpm WTP flow rate capacity. At a vertical rise rate of approximately 10 gpm/sf, the CAC has a
limited capacity of 1,835 gpm.
Filtration System. The filters are frequently subjected to rapid increases in filtration hydraulic loading
rates (known as filter bumping) under a variety of operational conditions. Filter bumping shortens filter
run time and degrades water quality. The periodic clarifier wash cycles described above, coupled with a
lack of automatic raw water pump throttling (one pump dedicated to one filter), are the principle reasons
why filter bumping can occur. Installation of variable-frequency drive (VFD) systems on the raw water
pumps would help eliminate the risk associated with filter bumping.
It is recommended that WTP backwash cycles be adjusted to increase bed expansion during backwash
given the available clearance and potential to help lengthen filter runs.
Clearwell. Due to operational constraints to accommodate future flows of 2,500 gpm, it may be
desirable to increase the clearwell volume.
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Caustic System. Currently, the WTP uses 25 percent sodium hydroxide solution, also referred to as
caustic, for finished water pH adjustment. A tanker truck fills an external caustic storage tank (Figure
2-5). The caustic application point is upstream of a static mixer following disinfection in the WTP
clearwell, as shown in Figure 2-6.
Caustic is a strong base and proper precautions must be maintained to protect plant operations staff
from exposure risks. Other chemicals may be more desirable for pH adjustment.
Figure 2-5. Caustic storage system
Figure 2-6. Caustic application point
Manganese Precipitation. Following caustic addition, formation of a brownish-colored precipitate has
periodically been noted in finished water sample tubing. Figures 2-7 and 2-8 show the brownish stain in
the finished water sampling equipment. According to the WTP staff, the brown staining fouls the chlorine
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analyzer equipment. There have also been occasional customer complaints of brown water during
hydrant use.
Figure 2-7. Brownish color in finished water sampling appurtenances
Figure 2-8. Stained tubing
A section of the stained tubing was sent to Columbia Analytical Services and the brownish precipitate
was determined to be mostly composed of manganese dioxide (MnO2). The testing results can be found
in Appendix C. The concentration of manganese in water supplied from the Haller well field has been
increasing; please refer to Section 4.3 for more information.
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The sodium hypochlorite used for disinfection oxidizes the manganese present in the water to insoluble
MnO2. The tendency for MnO2 to precipitate out of solution increases with increasing pH. The brownish
color is not seen until after caustic addition.
Since the brown precipitate was determined to be MnO2, several strategies to remedy this issue are
possible. Oxidation of manganese is time-sensitive, so relocating the injection point for the pre-filtration
disinfectant (currently sodium hypochlorite) as far upstream of the treatment trains as possible may be
desirable to allow the manganese to more effectively precipitate out of solution and be removed by the
filters. Alternatively, the use of potassium permanganate as a pre-filtration oxidizer and disinfectant may
be effective. Additionally, greensand filtration could be considered as a viable alternative for manganese
removal installed either upstream of the WTP or as a replacement for the existing anthracite/sand
media. Consideration of this latter option should involve further study, however, and simpler options
should likely be considered first.
To manage customer complaints, an aggressive distribution line flushing program is recommended to
help remove accumulations of manganese precipitate found in water system piping. Increasing
distribution system flows can dislodge these accumulations and lead to customer complaints.
Another potential option for reducing the MnO2 formation could be to relocate the caustic addition
upstream of the clearwell. Moving the caustic addition upstream of the clearwell may allow the MnO2 to
precipitate and to settle out in the clearwell instead of in the distribution system. However, this change
would increase pH in the clearwell. As a result, higher chlorine doses may become necessary to maintain
disinfection CT.
If the caustic addition remains in the same location, it is recommended that the chlorine analyzer be
moved upstream of the current caustic feed point (downstream of the clearwell) to reduce fouling of the
chlorine analyzer.
Finished Water Pipe Loop. The WTP staff has noticed variations in finished water pumping that may be
caused by air binding in the finished water pipe system. Air binding can create additional head loss,
resulting in flow reductions. The existing finished water pipe loop includes an overhead “goose-necked”
pipe section that is purged by only one small air release valve. It is recommended that an additional air
release valve be located upstream of the flow meter as shown in Figure 2-9. The WTP staff should also
evaluate if pump check valves are leaking air into the finished water pump columns during pump
shutdowns, as this may add extra air to the trapped pipe spool section.
Figure 2-9. Finished water pipe loop
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2.3 Airport Well Field
The City also obtains water supply from an Airport well field, in addition to the Haller well field water
supply. The Airport well field consists of one well located in pressure zone 342. The well site is situated
on City property at the airport in an industrial zoned area near 59th Avenue. The well and associated
mechanical, electrical, and telemetry equipment are enclosed in a fenced area within a building as
shown in Figure 2-10. An emergency generator is located adjacent to the well in its own separate
enclosure. Water from the well is pumped into pressure zone 342 following disinfection with sodium
hypochlorite.
Figure 2-10. Airport well field site location
2.3.1 Analysis of Airport Well Capacity and Expansion
The Airport well is in need of infrastructure improvements. Originally the well had a capacity of 580 gpm
and a depth of 185 feet. A 2009 well collapse has reduced the supply capacity of the well to
approximately 200 gpm. If increased water rights are obtained and transferrable to this well, then new
wells would need to be drilled and manganese and possibly iron treatment would likely be required.
Refer to Section 3 discussion of water rights and Section 4 for additional information on manganese
found in the Airport well.
Rehabilitation or replacement of the existing Airport well building is also needed to improve the facility’s
safety. The equipment is below grade and there are drainage problems which causes electrical hazards.
Figure 2-11 shows in the inside of the Airport well building.
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Figure 2-11. Equipment in Airport well building
PGG completed a report assessing the improvements required to increase capacity at the Airport well
field. The report is included in Appendix A and a summary is presented below. To increase well capacity
to 1,700 gpm, the City would need three to four additional new supply wells including replacement of the
existing Airport well. Additional wells could be installed in phases.
Expected well capacity, aquifer properties, and well field interference effects should be re-evaluated
after the installation and testing of the replacement wells and prior to the siting of additional new wells.
When siting any and all new Airport wells, the proximity of industrial facilities, airport fuel storage facili-
ties, and other sources of potential contamination that would fall within the Well Head Protection Area
should be considered since the aquifer is potentially susceptible to surface contamination due to the
absence of significant overlying confining layers. A cursory look at land use upgradient or southeast of
the Airport well suggests some potential sources of contamination. A detailed survey should be com-
pleted to identify all potential sources of contamination that might exist in proximity to the City’s Airport
well sites prior to installing any replacement or new supply wells.
Manganese and possibly iron concentrations should be anticipated to be above or marginally below
secondary MCLs for any Airport supply area well. Available water quality data are not sufficient to site or
screen wells in such way to reliably achieve water quality below the secondary MCL for iron and manga-
nese.
2.4 Operating Costs for Haller and Airport Well Fields
The well fields produce approximately 320 MG annually. Table 2-5 shows the annual costs by
expenditure item for an 11-month period. The highest operating cost is employee salaries and benefits
followed by Public Works Trust Fund (PWTF) loan repayments. Assuming an average monthly cost for the
twelfth month, the cost to produce water from the Haller and Airport well fields was $0.15 per 100
gallons or $1.12 per 100 cubic feet (ccf) in 2009.
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Table 2-5. 2009 Haller and Airport Well Fields Operating Costs
Expenditure Line Item Total Cost
Operating supplies $39,445
Operating permit $5,625
Regulatory compliance & equipment $11,352
Insurance $4,868
Public utility service $39,466
Repairs & maintenance $9,080
Telephone system $1,550
Salaries & benefits $231,054
PWTF loan payments $98,068
Total $440,500
Source: City records for 2009 water treatment plant expenses from January through November.
2.5 Snohomish PUD Interconnection
In July 1998, the City and Snohomish County PUD established a wholesale water agreement to
supplement the City’s existing water supply. The agreement allows the City to purchase a maximum of
1,000 gpm of finished water from the PUD for resale to the City’s water utility customers. The City
agreed to a steady use of water and to not use the supply to meet daily peak demands. The City
currently draws about 350 gpm. The agreement expires in 2018, but the City staff anticipate no
problems with renewing the agreement at 1,000 gpm.
The PUD’s main sources of water supply are interties to City of Everett transmission mains as shown in
Figure 2-12. The PUD has eight connections to Everett Pipeline 3, and five connections to Everett
Pipeline 5.
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Figure 2-12. Snohomish PUD water distribution system
Source: 2007 System Analysis and Capital Improvement Technical Memorandum
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2.5.1 Existing Operating Cost Summary
Table 2-6 summarizes the annual water usage and cost of the PUD water supply. The cost per cubic foot
has increased every year since 2004 at an average annual rate of 8 percent. The 2010 estimated
annual cost is approximately $330,250. The cost per 100 cubic feet has increased by approximately 80
percent since the 1998 wholesale water agreement when costs were initially set at $0.753 per 100
cubic feet.
Table 2-6. Summary of 2004-2010 Snohomish PUD Water Use and Cost
Year
Cost per
100 Cubic
Feeta
Cost
Increase
(%)
Annual
Usage (ft3)
Usage
Increase
(%)
Annual
Cost ($)
Annual Cost
Increase (%)
2004 0.809 14,742,482 $120,701
2005 0.917 11.8% 20,450,550 27.9% $182,838 34.0%
2006 0.983 6.6% 26,233,250 22.0% $253,994 28.0%
2007 1.034 5.0% 23,385,050 -12.2% $238,837 -6.3%
2008 1.087 4.9% 25,142,400 7.0% $270,172 11.6%
2009 1.172 7.3% 24,277,550 -3.6% $279,968 3.5%
2010b 1.360 13.8% 24,906,200 2.5% $330,251 15.2%
a. Cost per cubic foot begins in April of the year listed.
b. 2010 annual usage and annual costs are estimated.
Source: City records for PUD water purchase rates and costs from 2004 to 2010.
2.5.2 2028 Capacity Improvements
A 2007 System Analysis and Capital Improvement Report evaluated the infrastructure improvements
required to supply the City with 3,000 gpm of PUD water in 2028. Table 2-7 summarizes the additional
improvements and costs. To continue providing the City with 1,000 gpm of PUD water, the PUD would
need to spend approximately $27M to maintain this flow based on system growth improvements. To
supply the City with 3,000 gpm capacity, the PUD will need to take on some additional improvements
totaling $40.5M. The City would be responsible for paying $13.4M (the difference) to increase the PUD
supply from 1,000 gpm to 3,000 gpm. The recommended improvements for the 1,000 gpm and 3,000
gpm allocation are shown in Figures 2-13 and 2-14, respectively.
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Table 2-7. PUD Improvements Needed to Maintain and Expand PUD Supply to City of Arlington
Recommended
Improvement
Arlington @
1,000 gpm Cost Estimate
Arlington
@ 3,000
GPM Cost Estimate
Cost
Difference
P-1 16-IN $4,958,000 18-IN $5,578,000 $620,000
P-3 24-IN $2,299,000 30-IN $2,874,000 $575,000
P-18 NOT NEEDED 18-IN $2,323,000 $2,323,000
P-22 NOT NEEDED 16-IN $830,000 $830,000
P-23 16-IN $1,252,000 18-IN $1,408,000 $156,000
P-25 NOT NEEDED 12-IN $627,000 $627,000
P-27 NOT NEEDED 12-IN $617,000 $617,000
P-28 16-IN $3,347,000 24-IN $5,021,000 $1,674,000
Machias Pump Station 6,000 GPM $100,000 7,000 GPM $200,000 $100,000
Getchell Pump Station 1,500 GPM $500,000 3,000 GPM $550,000 $50,000
East Hewitt Pump Station 3,000 GPM $100,000 5,000 GPM $175,000 $75,000
Getchell Tank 9.2 MG $10,700,000 9.7 MG $11,300,000 $600,000
Burn Rd Tank 3.3 MG $3,860,000 7.7 MG $9,000,000 $5,140,000
TOTAL $27,116,000 $40,503,000 $13,387,000
Source: 2007 System Analysis and Capital Improvement Technical Memorandum
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Figure 2-13. 1,000 gpm system improvements in 2028
Source: 2007 System Analysis and Capital Improvement Technical Memorandum
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Figure 2-14. 3,000 gpm system improvements in 2028
Source: 2007 System Analysis and Capital Improvement Technical Memorandum
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Section 3
Water Rights and Water Demand
Summary
This section outlines the City’s existing water supply sources and associated water rights and compares
water rights to anticipated future water demands.
3.1 Water Rights
Water rights held by the City of Arlington for the Haller and the Airport well fields are summarized in the
following sections.
3.1.1 Haller Well Field Supply
Water rights for the Haller well field were originally obtained in 1927 by Puget Sound Power and Light
Company (PSPL). This water right (SWC 194), a surface water certificate with a priority date of October
10, 1924, was designated to supply water to Arlington. In 1939, the City purchased “…the water system
in and adjacent to the City of Arlington, Washington…” from PSPL. This purchase included “…all public
and private grants or rights of way and operating rights for the operation of said water works.”
In 1964, after constructing two new Haller wells and requesting assistance from the Washington State
Department of Conservation Division of Water Resources, a predecessor to the current Department of
Ecology, the City was told that no water right records for the Haller well field could be located. The City
subsequently applied for and received water right GWC 5169 for the Haller well field, which has a priority
date of February 12, 1965.
In 2005, when it began to appear that the entire Stillaguamish River basin could be closed to the
development of new water supply given in-stream flow concerns, the City of Arlington began to further
examine water rights within the basin to evaluate the potential for water right transfers. During this
evaluation, the City discovered documentation of the original PSPL water right (SWC 194). Through
current water system planning efforts, the City is in the process of formally reasserting the PSPL water
right and is bringing the water right and relevant documentation to the attention of the Department of
Ecology. The Washington Supreme Court’s unanimous affirmation of the 2003 municipal water law in
2010 supports the City’s position that inchoate water under all of the above water rights remains a valid
component of its water supply portfolio.
The existing water rights and potential water right transfers for the Haller well field are summarized in
Table 3-1. A water right transfer from the Klein water right claim (300889CL(A)) to the City’s Haller well
field was approved by the Department of Ecology in 2009. As shown in Table 3-1, the Haller well field
has a total of 4,079 gpm in instantaneous water rights, with a potential for a total of 4,369 gpm in
instantaneous water rights following the transfer of the Graafstra and Neunzig water rights to the City.
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Table 3-1. Haller Well Field Water Rights
Water Right
Number
Priority
Date Type
Maximum
Instantaneous
Withdrawal Rate (gpm)
Maximum Annual
Withdrawal Rate (acre-
ft/year)
Notes
Certificate
SWC 194 (PSPL)
October
10, 1924
Surface
water
2,244
(Specified as 5.0 cfs)
Not specified
(3,620 acre-ft/year based on
5.0 cfs)
Original PSPL water right
Claim 300889CL(A)
(Klein)
1931 Groundwater 135 72.18a Water right transferred to
City from Klein in 2009
Certificate GWC
5169
December
2, 1965
Groundwater 1,700 1,344
GWC 5169 + Klein 1,835 1,416.18b
PSPL + GWC 5169 + Klein 4,079 5,036.18b
Certificate
S1-*10680CWRIS
(Graafstra)
1951 Surface
Water
100 125 Potential water right
transfer to City from
Graafstra
Certificate
S1-*18929CWRIS
(Graafstra)
1965 Surface
Water
100 50 Potential water right
transfer to City from
Graafstra
Certificate
G1-*02115CWRIS
(Neunzig)
1951 Groundwater 90 35 Potential water right
transfer to City from
Neunzig
Total including potential transfers 4,369 5,246.18
a. A maximum of 68.94 acre-ft of this water right is to be withdrawn seasonally (March 1 through September 30). The remaining 3.24 acre-ft
may be withdrawn year-round.
b. Annual water rights shown as additive.
3.1.2 Airport Well Field Supply
The City has two existing groundwater rights associated with the Airport well field. The City also applied
for additional water rights for the Airport well field in 1992 under application G1-26641. This water right
application is still in process.
The Airport well field existing water rights, water right applications, and potential water right transfers are
summarized in Table 3-2. The Airport well field has a total of 580 gpm in instantaneous water rights.
With approval of application G1-26641, a total instantaneous withdrawal of 1,480 gpm would be
available at the Airport well field. With the transfer of the National Food Corporation and Turf Farm water
rights, the Airport well field would have a total of 1,780 gpm in instantaneous water rights.
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Table 3-2. Airport Well Field Water Rights
Water Right
Number
Priority
Date Type Maximum Instantaneous
Withdrawal Rate (gpm)
Maximum Annual Withdrawal
Rate (acre-ft/year) Notes
Primary Supplemental
Certificate
GWC5170
1965 Groundwater 200 320
Certificate G1-
24900C
September
17, 1986
Groundwater
380 376
Annual
withdrawal rate is
non-additive
Total 580 320 376
Application G1-
26641
July 7,
1992
Groundwater 900 850 Application for
continuous usage
Total including applications 1,480 1,170 376
Certificate G1-
22622CWRIS
(National Food
Corporation)
1975 Groundwater
150 76.4
Potential water
right transfer to
City from
National Food
Corporation
Certificate G1-
23085GWRIS
(Turf Farm)
April 17,
1978
Groundwater
150 80
The City owns this
groundwater right
for irrigation.
Potential to
transfer use to
municipal.
Total including potential transfers 1,780 2,816.4
3.2 Demand Forecast
Existing and future water system demands are presented in the City’s Draft 2010 WSP. The City’s water
system primarily provides service to single-family residential customers (85 percent), with multifamily
residential (4 percent), commercial/industrial (9 percent), and other (2 percent) making up the
remainder of the water customers. The City’s 2008 per capita water demand is 87 gallons per capita per
day (gpcd) based on the total annual supply in 2008 divided by the 2008 residential service area
population. The majority of water system demands (74 percent) are within the 342 pressure zone, with
25 percent in the 520 pressure zone, and the remaining demands distributed throughout the 608 and
710 pressure zones. Distribution system leakage (DSL) averaged 6 percent from 2006 through 2008.
Water system demands are projected using the per capita water demand of 87 gpcd and projected
population data. Projections were made with and without reductions in demands per water use efficiency
(WUE) goals. WUE goals for the City include 2 percent water use reduction per capita by 2014 and a 5
percent reduction per capita by 2018. The City’s projected water demands are shown in Table 3-3.
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Table 3-3. Projected Water Demands
Projected Demand Actual 2008 2014
(6 Year)
2028
(20 Year)
2058
(50 Year)
Average day demand (gpm)
Without WUE goals 969 1,188 1,852 3,376
With WUE goals N/A 1,164 1,760 3,207
Maximum day demand (gpm)
Without WUE goals 1,956 2,399 3,742 6,818
With WUE goals N/A 2,351 3,555 6,478
Peak hour demand (gpm)
Without WUE goals 3,526 4,324 6,742 12,287
With WUE goals N/A 4,237 6,405 11,673
Source: Draft 2010 City of Arlington Water System Plan, March 2010, RH2 Engineering.
As shown in Table 3-3, average day demands (ADD) for the City are projected to almost double in the
next 20 years, without WUE savings. The City will continue to strive to meet WUE goals; however,
planning efforts are based on water demand projections without WUE savings in order to ensure that
adequate water supply is available if WUE goals are not met.
3.3 Water Rights Analysis
The existing capacities of the Haller and Airport well fields are compared to associated water rights in the
following sections. An analysis comparing existing and projected future water system needs to identified
water rights, including a forecast of additional water rights to be obtained through new and transfer
applications, is also included.
3.3.1 Haller Well Field Supply
The rated capacities of the wells in the Haller well field are summarized in Table 3-4.
Table 3-4. Haller Well Field Capacity
Well Rated Capacity (gpm) Usage Notes
Well 1R 570 Emergency High iron and manganese
Well 2 570 Secondary Rehabilitated in 2001
Well 3 1,140 Primary Two pumps, 570 gpm each, operated simultaneously
Total Haller well field rated capacity
without emergency supply
1,710 Includes Wells 2 and 3. See Section 2 for discussion
and analysis of WTP existing capacity.
The existing capacity of the Haller well field is compared to potential water rights in Table 3-5.
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Table 3-5. Haller Well Field Water Right Analysis
Water Right Scenario Total Instantaneous Water Right (gpm) Existing Haller Well Field Capacity without
Emergency Supply (gpm)
GWC 5169 + Klein 1,835 1,500
PSPL + GWC 5169 + Klein 4,079 1,500
PSPL + GWC5159+ Klein +
Graafstras a + Neunzig a
4,369 1,500
PSPL + GWC5159+ Klein +
Graafstras + Neunzig +Cemmentaryb
+ Hammerb
4,619 1,500
a. At least three potential water rights transfers are possible by 2016: (1) 1951 Graafstra: 100 gpm, (2) 1965 Graafstra: 100 gpm, and (3)
1951 Neunzig: 90 gpm.
b. An additional two water rights transfers are possibly by 2020: (1) Cementery: 125 gpm and (2) Hammer: 125 gpm
3.3.2 Airport Well Field Supply
There is currently one existing well at the Airport well field. Both the existing and applied-for
instantaneous water rights are compared to the existing well capacity in Table 3-6. Potential water rights
through 2020 are also included in the table.
Table 3-6. Airport Well Field Water Right Analysis
Water Right Scenario Total Instantaneous Water Right (gpm) Existing Airport Well Capacity (gpm)
Existing 580 200
Existing + Application G1-26641 1,480 200
Existing + Application G1-26641 +
National Foods + Turf Farm a
1,780 200
a. At least two potential water rights transfers are possible by 2020: (1) National Foods: 150 gpm and (2) Turf Farm: 150 gpm.
3.4 Target Capacity Projections
The City is assessing future Haller well field, WTP, Airport well field, and PUD capacity expansions. The
ability of the City to meet projected water demands in part depends on the outcome of future decisions
by the Department of Ecology related to water rights determinations. Figure 3-1 compares the City’s
projected maximum day demand (MDD) to various water right scenarios. The wholesale intertie with the
PUD is also included in the scenarios with a 1,000 gpm or 3,000 gpm supply capacity depending on the
scenario. The scenarios shown in Figure 3-1 are described in detail in Table 3-7. These scenarios shown
in Table 3-7 represent possible water supply options that the City can pursue for water rights. Discrete
water treatment and supply alternatives that stem from these water supply scenarios are discussed in
Section 5.
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Figure 3-1. Projected demand versus water right supply capacity
Table 3-7. Description of Water Supply Scenarios
Water Supply
Scenario Description
S0 S0 describes existing, recognized water supplies at their full water right or contract rate for instantaneous or maximum
day capacity. It excludes any water rights that aren't fully recognized, and any water rights whose transfers are
proposed or in process.
S1 S1 maintains the supplies included in S0, and supports production capacity at both the Haller and Airport well fields
using the following assumptions. Haller capacity is expanded in 2011 through full recognition of the PSPL (1924)
water right as additive to 1965 GWC 5169; and successful transfer of the Graafstra and Neunzig water rights. Haller
capacity is further expanded by the transfer of the City's irrigation water rights at the cemetery and Hammer con-
structed wetland by 2020. Airport capacity is expanded in 2014 through development of additional water using the
City's 1992 application, and transfer of the National Foods irrigation water right. Airport capacity is further expanded
by the transfer of the City's turf farm irrigation water right by 2020.
S2 S2 is basically S1 without the PSPL water right, and demonstrates capacity if the PSPL water right is not recognized.
S3 S3 is basically S2 but expands the City's PUD supply by an additional 2,000 gpm through contract amendment by
2020. As with S2, it excludes the PSPL water right
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Section 4
Regulatory Constraints and Water
Quality Objectives
This section identifies all the current and pending regulations that could impact the City of Arlington’s
ability to meet current and anticipated future water quality objectives. These regulations will affect water
treatment and water quality criteria for the finished water from the plant and the Airport well field, and
the water delivered to the consumer’s tap.
4.1 Regulatory Overview
The state and federal drinking water regulations that relate directly to contaminant concentrations in
drinking water are summarized in this section. The USEPA is responsible for developing and
implementing drinking water regulations under the 1974 federal Safe Drinking Water Act (SDWA). States
can either adopt the federal regulations or develop their own regulations with more stringent standards.
The Washington State Department of Health (DOH) is the authority responsible for implementing and
enforcing drinking water regulations within Washington State. For all regulated drinking water
contaminants, the State has essentially adopted the federal regulations.
The following sections summarize the federal and state requirements. State requirements are identified
only when they are more stringent than the corresponding federal regulations. The numeric maximum
contaminant levels (MCLs) and secondary standards are summarized in Appendix D. The MCL is the
highest level of a specific contaminant allowed in drinking water. Some contaminants have a treatment
technology requirement in lieu of or in addition to the MCL. Additionally, USEPA does not enforce
secondary standards. They are established only as guidelines to assist public water systems (PWSs) in
managing their drinking water for aesthetic considerations such as taste, color, and odor, and are not
considered to present a risk to human health at the secondary standard level.
4.1.1 Federal Regulations
Federal water quality regulations are summarized in Table 4-1. The most recently promulgated federal
regulations relevant to Arlington are the Long Term 2 Enhanced Surface Water Treatment Rule
(LT2ESWTR) and the Stage 2 Disinfectants/Disinfection By-Products Rule (D/DBPR). These regulations
augment the previously promulgated regulations, the Interim Enhanced Surface Water Treatment Rule
(IESWTR), the Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR), and the Stage 1
D/DBPR. The goal of the new rules is to provide a higher level of protection against microbial
contaminants, while limiting the production of potentially carcinogenic DBPs.
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Table 4-1. Summary of USEPA Drinking Water Quality Regulations
Regulation Major Requirements
National Primary Drinking
Water Regulations
• Currently established for 92 contaminants, including turbidity, 8 microorganisms,
4 radionuclides, 19 inorganic contaminants, and 60 organic contaminants.
• 83 of the 92 contaminants have MCLs and maximum contaminant level goals (MCLGs), with
treatment technique requirements for the remaining 9.
• 15 additional contaminants have secondary (aesthetic) standards.
Total Trihalomethanes Rule
Promulgated in 1979
• Established an MCL of 100 micrograms per liter (μg/L) for the sum of four trihalomethanes
(THMs): chloroform, bromodichloromethane, dibromochloromethane, and bromoform.
• Compliance determined as a running annual average (RAA) of quarterly samples.
Surface Water Treatment Rule
Promulgated in 1989
• Requires that a detectable disinfectant residual be present in all portions of the distribution
system (heterotrophic plate count [HPC] less than 500 colony forming units [CFU]/mL equivalent
to a detectable residual).
• Requires 3-log giardia inactivation/removal. Conventional systems receive a 2.5-log credit and
direct filtration systems receive a 2-log credit for meeting filter effluent turbidity requirements.
Remaining requirements must be met through disinfection.
• Requires 4-log virus inactivation/removal. Conventional systems receive a 2-log credit and direct
filtration systems receive a 1-log credit for meeting filter effluent turbidity requirements.
Remaining requirements must be met through disinfection.
• Requires that combined filter effluent turbidity not exceed 0.5 nephelometric turbidity units (NTU)
in more than 5% of samples each month.
Total Coliform Rule
Promulgated in 1989
• Requires that less than 5% of distribution samples collected each month be positive for total
coliform.
• Requires a detectable disinfectant residual at all points in the distribution system (HPC less than
500 CFU/mL considered equivalent to a detectable residual).
Interim Enhanced Surface
Water Treatment Rule (IESWTR)
Promulgated in 1998
• Establishes an MCLG of zero for cryptosporidium.
• Requires combined effluent turbidity of less than 0.3 NTU in 95% of samples collected each
month.
• Establishes requirements for individual filter effluent turbidities, with associated requirements for
a comprehensive performance evaluation of underperforming filters.
• Requires that new finished water reservoirs be covered.
• Requires sanitary surveys at 3-year intervals.
• Requires disinfection benchmarking.
Stage 1 Disinfectants/
Disinfection By-Products Rule
(D/DBPR)
Promulgated in 1998
• Establishes MCLs for the following DBPs: total trihalomethanes (TTHMs) (80 μg/L), haloacetic
acids (HAAs) (60 μ/L), bromate (10 μg/L), and chlorite (1 mg/L). THM and HAA compliance is
based on an RAA of distribution system samples.
• Establishes maximum residual disinfectant levels (MRDLs) for the following disinfectants: free
chlorine (4 mg/L), chloramines (4 mg/L), and chlorine dioxide (0.8 mg/L). Compliance based on
an average of distribution system samples.
• Establishes enhanced coagulation requirements requiring total organic carbon (TOC) removals
based on raw water TOC and alkalinity. Purpose is to optimize removal of DBP precursors.
Modified Lead and Copper Rule
Promulgated in 2000
• Maintains MCLGs (0 mg/L for lead and 1.3 mg/L for copper) and action levels (ALs)
(0.015 mg/L for lead and 1.3 mg/L for copper) established in the 1991 Lead and Copper Rule.
• Compliance requires that less than 10% of distribution system samples exceed action levels.
• Establishes additional requirements, including demonstration of optimal corrosion control, lead
service line replacements, public education, monitoring, analytical methods, etc.
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Table 4-1. Summary of USEPA Drinking Water Quality Regulations
Regulation Major Requirements
Arsenic Rule
Promulgated in 2001
• Establishes an MCL of 10 μg/L for arsenic.
Filter Backwash Recycle Rule
Promulgated in 2001
• Requires that all recycle streams be returned prior to or at the point of primary coagulant
addition.
• Requires that information on recycle streams be provided to the DOH for evaluation.
Long-term 1 Enhanced Surface
Water Treatment Rule
(LT1ESWTR)
Promulgated in 2002
• Extended requirements of the IESWTR to utilities serving less than 10,000 persons.
Long-term 2 Enhanced Surface
Water Treatment Rule
(LT2ESWTR)
Promulgated in 2006
• Assigns utilities to one of four “bins” based on raw water cryptosporidium concentrations.
• Each bin has associated requirements for additional cryptosporidium treatment.
• Includes a toolbox of options for receiving cryptosporidium reduction credits, including watershed
control, disinfection, and filtration.
• Bin assignment is based on the average of the 12 consecutive highest months within a 2-year
period of monthly cryptosporidium samples.
Stage 2 D/DBPR
Promulgated in 2006
• Does not change the MRDLs or MCLs established in the Stage 1 Rule.
• Requires an Initial Distribution System Evaluation (IDSE) to identify sites with high DBP levels.
• Systems with no samples with TTHM/HAA levels exceeding 40/30 ug/L can apply for an IDSE
waiver.
• Compliance schedule is based on population of the PWS.
• 6 to 8 years following promulgation, requires compliance with 80 μg/L TTHM and 60 μg/L HAA
based on a location running annual average (LRAA) at each site.
4.2 Constituents of Concern to Water Purveyors
The following section provides a description of biological and chemical contaminants that affect drinking
water quality.
4.2.1 Microbiological Water Quality
One major function of water treatment is to remove or inactivate pathogenic organisms. Primary sources
of microbiological contaminants are grazing and wild animals, storm-sewer discharges, wastewater
treatment effluents and septic spills, and to a lesser degree, body-contact recreation within surface-
water sources. Pathogen concentrations are reduced through a combination of removal by filtration
processes and chemical disinfection. Chemical oxidants may also provide other benefits in addition to
disinfection, including the destruction of compounds that cause taste and odor problems.
Both state and federal regulations are focused on the removal of four major pathogens/pathogen
groups: coliform bacteria, giardia, viruses, and cryptosporidium. For three of the pathogen groups,
removal requirements depend on the level of microbial contamination of the source water. Turbidity is
also used as a surrogate for microbial water quality and is discussed below.
4.2.1.1 Coliform Bacteria
Coliform bacteria are used as an indicator of pathogenic contamination. Coliform bacteria are directly
regulated under the Total Coliform Rule. A violation of the non-acute bacteriological MCL standards,
regulated by DOH, occurs if more than 5 percent of monthly distribution system samples collected are
positive for coliform bacteria for a system that collects 40 samples or more per month. For a system that
collects fewer than 40 samples per month, a violation occurs if there is one total coliform positive
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sample during a month. Positive samples require additional action, including further testing for fecal
coliform, as well as collection of additional distribution system samples.
Additionally, the DOH regulations for a determination of a violation of an acute bacteriological MCL
standard requires public notification if any of the following conditions are met:
Fecal coliform is present in a repeat sample.
E. coli is present in a repeat sample.
Coliform presence in a repeat sample as a follow-up to a sample showing the presence of E. coli
or fecal coliform.
4.2.1.2 Giardia and Viruses
Giardia and viruses are regulated under the SWTR. The rule requires at least 4-log (99.99 percent) virus
inactivation/removal and 3-log (99.9 percent) inactivation/removal of giardia between a point where raw
water is not subject to recontamination by surface water runoff and a point downstream before or at the
first customer. Direct filtration plants, such as the current treatment facilities at Arlington, are granted a
2.0-log removal credit for giardia. Conventional treatment plants and membrane treatment plants are
generally granted a 2.5-log removal credit.
4.2.1.3 Cryptosporidium
Reduction of cryptosporidium is regulated under LT2ESWTR, published in the Federal Register on
January 5, 2006. Under this rule, 24 months of source water monitoring for cryptosporidium must be
initiated by April 2008 for systems serving a population 10,000 to 49,999 people. By March 2010, the
initial round of source water monitoring must be completed and by September 2010, filtered systems
must report their “bin” classification to USEPA for approval (see Table 4-2).
As shown in Table 4-2, utilities will be assigned to one of four “bins” according to average levels of
cryptosporidium in their source water. The bin assignments have associated treatment requirements
ranging from no additional treatment to a required 2.5 logs of additional treatment. The treatment
requirements listed in Table 4-2 will apply to the water purveyors if a conventional, direct, slow-sand, or
diatomaceous filtration is used. Requirements for alternative filtration technologies will be determined
by the DOH. Arlington is currently in Bin 1, which indicates that Arlington is not required to provide any
additional treatment for cryptosporidium.
Table 4-2. USEPA LT2ESWTR Bin Assignment for Cryptosporidium Reduction Requirements a
Bin Number Average Cryptosporidium Concentration Additional Treatment Requirements
1 < 0.075 cysts /L No additional treatment
2 ≥ 0.075 cysts /L and < 1.0 cysts /L
1-log additional treatment for conventional, and
slow sand or diatomaceous filtration, 1.5-log for
direct filtration b
3 ≥ 1.0 cysts /L and < 3.0 cysts /L
1-log additional treatment for conventional, and
slow sand or diatomaceous filtration, 2.5-log for
direct filtration b,c
4 3.0 cysts /L
2.5-log additional treatment for conventional, and
slow sand or diatomaceous filtration, 3-log for
direct filtration b,c
a. For conventional treatment systems in full compliance with the SWTR, IESWTR, and LT1ESWTR.
b. Utilities using alternative filtration falling under Bins 2, 3, or 4 must meet treatment requirements determined by the State.
c. Utilities falling under Bins 3 or 4 must meet 1.0 log of the required treatment using ozone, UV, chlorine dioxide, membranes, bag
filtration, cartridge filtration, or bank filtration.
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A unique aspect of the cryptosporidium regulation under the LT2ESWTR is that utilities can achieve
credits for prevention, removal, or inactivation through a number of pathways. Credits of potential
interest to Arlington are summarized in Table 4-3.
Table 4-3. USEPA LT2ESWTR Microbial Toolbox for Cryptosporidium Treatment Credits
Toolbox Option Cryptosporidium Treatment Credit
Source protection and management toolbox options
Watershed control program • 0.5-log credit for State-approved program comprising required elements, annual program status
report to State, and regular watershed survey.
Alternative source/intake
management
• No prescribed credit. Utilities may conduct simultaneous monitoring for treatment bin
classification at alternative intake locations or under alternative intake management strategies.
Pre-filtration toolbox options
Pre-sedimentation basin with
coagulation
• 0.5-log credit during any month when pre-sedimentation basins achieve a monthly mean
reduction of 0.5-log or greater in turbidity or alternative State-approved performance criteria.
Basins must be operated continuously with coagulant addition and all flows must pass through
basins.
Bank filtration
• 0.5-log credit for 25-foot setback; 1.0-log credit for 50-foot setback; horizontal and vertical wells
only; aquifer must be unconsolidated sand containing at least 10% fines (as defined by rule);
average turbidity in wells must be less than 1 NTU. Systems using existing wells followed by
filtration must monitor the well effluent to determine bin classification and are not eligible for
additional credit.
Treatment performance toolbox options
Combined filter performance • 0.5-log credit for combined filter effluent turbidity less than or equal to 0.15 NTU in at least 95%
of measurements each month.
Individual filter performance
• 0.5-log credit (in addition to 0.5-log combined filter effluent credit) if individual filter effluent
turbidity is less than or equal to 0.15 NTU in at least 95% of samples each month in each filter
and is never greater than 0.3 NTU in two consecutive measurements in any filter.
Demonstration of performance • Credit awarded to unit process or treatment train based on a demonstration to the State with a
State-approved protocol.
Additional filtration toolbox options
Bag and cartridge filters
• Up to 2.0-log credit with demonstration of at least 1-log greater removal in a challenge test when
used singly. Up to 2.5-log credit with demonstration of at least 0.5-log greater removal in a
challenge test when used in series.
Membrane filtration • Log credit equivalent to removal efficiency demonstration in challenge test for device if supported
by direct integrity testing.
Second stage filtration • 0.5-log credit for second separate granular media filtration stage if treatment train includes
coagulation prior to first filter.
Slow sand filters • 2.5-log credit as a secondary filtration step; 3.0-log credit as a primary filtration process. No prior
chlorination for either option.
Inactivation toolbox options
Chlorine dioxide • Log credit based on measured CT (concentration x time) in relation to CT table.
Ozone • Log credit based on measured CT in relation to CT table.
UV • Log credit based on validated UV dose in relation to UV dose table; reactor validation testing
required to establish UV dose and associated operating conditions.
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4.2.1.4 Turbidity
Turbidity is a concern in drinking water because it can reduce the effectiveness of disinfection by
shielding microorganisms. It is also used as a surrogate measure for potential pathogenic contamination
and as a measure of filtration performance.
The IESWTR included new requirements for filtered water turbidities. In particular, it introduced
monitoring of individual filter effluents, rather than just combined-filter effluent. The rule requires that
individual filter effluent turbidities not be greater than 1.0 NTU in any two consecutive samples at any
time, or greater than 0.5 NTU after the filter has been in operation for 4 hours. Individual filters
exceeding these standards are subject to a comprehensive performance evaluation. The rule also
requires that combined filter effluent turbidities be less than 0.3 NTU in 95 percent of samples collected
each month.
4.2.2 Disinfectants and Disinfection By-Products
DBPs are produced through the reaction of chemical disinfectants with natural organic matter (NOM)
present in the source water. DBPs are a concern due to a number of confirmed or suspected health
effects, including increased rates of cancer, miscarriages, and developmental defects. The DBPs of
greatest concern are bromate, total trihalomethanes (TTHMs), and five haloacetic acids (HAA5). Bromate
is formed through the interaction of ozone with bromide in the source water. The current USEPA MCL for
bromate is 0.01 mg/L. TTHMs and HAAs are formed through the interaction of chlorine with NOM in the
source water.
Under the Stage 2 D/DBPR, both TTHMs and HAAs will be regulated based on samples collected at a
number of locations throughout the distribution system. Utilities must conduct an Initial Distribution
System Evaluation (IDSE) to identify locations within their distribution systems representing maximum
TTHM and HAA concentrations. Compliance will be based on a locational running annual average (LRAA)
of quarterly samples collected at each of the sample locations.
The MCLs for DBPs are summarized in Table 4-4, which also includes maximum residual disinfectant
levels (MRDLs) that regulate the disinfectant concentrations in the distribution system based on a
system-wide annual average. All values are from the recently promulgated USEPA Stage 1 and 2
D/DBPRs, which will supersede previous DBP regulations. The schedule for systems serving 10,000 to
49,999 people (applicable to size of the City) is summarized in Table 4-5 below.
Table 4-4. USEPA Stage 1/2 D/DBP Rules Disinfectants and Disinfection By-Product Limits
Disinfection By-Products Maximum contaminant level
Total trihalomethanes 80 μg/L
Haloacetic acids 60 μg/L
Disinfectant Maximum residual disinfectant level
Chlorine 4 mg/L
Chloramines 4 mg/L
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Table 4-5. Stage 2 Disinfectants and Disinfection By-Products Rule Compliance
Schedule for Systems Serving 10,000 to 49,999 people
Category Deadline
Monitoring plan or waiver submittal October 1, 2007
Monitoring completion a September 30, 2009
Final IDSE report submittal January 1, 2010
Compliance with rule requirements July 2014
a. The monitoring plan requires a sample collection frequency of once every quarter during the month of
highest DBP occurrence historically, with four distribution system monitoring locations per sampling period.
4.2.3 Chemical Contaminants
Chemical contaminants are regulated under the National Primary Drinking Water Regulations. These
regulations currently address 92 contaminants, including 19 inorganic and 60 organic chemicals and
4 radionuclides. In addition to the primary standards, secondary standards have been established for
15 additional parameters. The federal and state primary and secondary drinking water standards are
listed in Appendix D.
4.2.4 Emerging Contaminants
Emerging contaminants are chemical and microbial contaminants that are not currently regulated, but
may be regulated in the future. Two main sources of information are the USEPA’s Contaminant
Candidate List (CCL) and the Information Collection Rule (ICR).
CCL 1, published in 1998, included 10 microbial and 50 chemical contaminants. The purpose of the CCL
is to identify contaminants that are not yet subject to regulation, but are known or anticipated to occur in
PWSs, and may require future regulation under the SDWA. CCL 2 was published in 2005 and includes
the contaminants on CCL 1 for which a regulatory determination was not made. CCL 2 does not include
the nine CCL 1 contaminants for which sufficient information existed to determine that National Primary
Drinking Water Regulations need not be developed. These include one microbial and eight chemical
contaminants. In October 2009, USEPA published the final CCL 3 list, which included 104 chemical
contaminants and 12 microbial contaminants. The list includes, among others, pesticides, biological
toxins, DBPs, chemicals, and waterborne pathogens.
Contaminants requiring further information on occurrence have been monitored under the Unregulated
Contaminant Monitoring Rule (UCMR). The first cycle of the rule (UCMR 1) was promulgated in 1999 and
included a list of 34 contaminants. The second cycle of the rule (UCMR 2), published in 2007, is divided
into two sub-lists: List 1 Assessment Monitoring chemical contaminants and List 2 Screening Survey
chemical contaminants (see Table 4-6). The Assessment Monitoring contaminants include two
pesticides, five flame retardants, and three explosives. The Screening Survey contaminants include
acetanilide pesticide parent compounds and their degradation products and nitrosamines.
All PWSs serving more than 10,000 people and a subset of those serving 10,000 or fewer are required
to monitor for the List 1 (Assessment Monitoring) contaminants. All PWSs serving more than 100,000
people and subsets of those serving 10,001 to 100,000 and 10,000 or fewer are required to monitor for
the List 2 (Screening Survey) contaminants. UCMR 2 requires four consecutive quarterly rounds of
sampling at the entry points to the distribution system between 2008 and 2010.
Many of the contaminants monitored under the UCMR were identified in the ICR, which was promulgated
in May 1996. The purpose of the ICR is to collect occurrence and treatment information to help evaluate
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the need for possible changes to the current SWTR and evaluate the need for future regulation of
disinfectants and DBPs. The data were published in December 1999.
Table 4-6. USEPA UCMR 2 Monitoring List
List 1 Assessment Monitoring List 2 Screening Survey
Dimethoate
Terbufos sulfone
2,2',4,4'-tetrabromodiphenyl ether (BDE-47)
2,2',4,4',5-pentabromodiphenyl ether (BDE-99)
2,2',4,4',5,5'-hexabromobiphenyl (HBB)
2,2',4,4',5,5'-hexabromodiphenyl ether (BDE-153)
2,2',4,4',6-pentabromodiphenyl ether (BDE-100)
1,3-dinitrobenzene
2,4,6-trinitrotoluene (TNT)
Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX)
Acetochlor
Alachlor
Metolachlor
Acetochlor ethane sulfonic acid (ESA)
Acetochlor oxanilic acid (OA)
Alachlor ethane sulfonic acid (ESA)
Alachlor oxanilic acid (OA)
Metolachlor ethane sulfonic acid (ESA)
Metolachlor oxanilic acid (OA)
N-nitroso-diethylamine (NDEA)
N-nitroso-dimethylamine (NDMA)
N-nitroso-di-n-butylamine (NDBA)
N-nitroso-di-n-propylamine (NDPA)
N-nitroso-methylethylamine (NMEA)
N-nitroso-pyrrolidine (NPYR)
4.2.4.1 Possible Future Regulatory Scenarios
An assessment of future regulatory scenarios was recently provided on March 10, 2010, by Eva
Niemenski, Research Environmental Engineer, Utah Department of Environmental Quality, who serves as
a regulatory and water quality background expert. Summary of our discussion with Ms. Niemenski on
future regulations and other resources include:
Stage 3 D/DBPR: TTHMs and HAA5s are currently regulated as a group on an LRAA basis at 80
µg/L for TTHMs and 60 µg/L for HAA5s under the Stage 2 D/DBPR. Under a potential future
Stage 3 D/DBPR, it is likely that TTHM and HAA5 regulations will change to single-sample, not to
exceed the above numerical limit in the distribution system, as opposed to LRAA. As an
increasing amount of health-effects data become available, regulations may also be directed to
individual species of TTHMs and HAA5s to reduce associated health effects (Shaw et al., 2009).
Another likely scenario is that at least one more HAA species (most likely iodinated HAAs) will be
added to the list (HAA6), but the numerical objective of HAA6 will continue to be 60 µg/L. Shaw
et al. (2009) predict that the numerical limit for bromate may reduce from 10 µg/L (current) to 5
µg/L in the future.
Endocrine disrupting compounds (EDCs) and pharmaceuticals and personal care products
(PPCPs): Future regulations on EDCs and PPCPs are not likely expected any time in the near
future because of expensive detection methods, cost of modifying existing treatment plants, and
the high operational cost of treating of these compounds at water treatment plants. Shaw et al.
(2009) state that new regulations could be based on a common mechanism for toxicity (e.g.,
endocrine disruption) instead of by individual compound. Alternatively, regulations could require
a specific treatment technology (e.g., granular activated carbon) for an array of chemicals,
instead of setting standards for specific MCLs (AWWARF, 2005).
CCL: USEPA may eliminate CCL lists in the future due to the high cost involved in tracking the
contaminants over the long term and developing a list periodically.
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4.3 Raw and Finished Water Quality
This section presents a summary of raw and finished drinking water quality supplied by the City. Samples
were taken from the Haller well field (feeding the water treatment plant), the Airport well, and within the
City distribution system.
Overall, the data analysis suggest that raw water quality from the Haller well field and the Airport well
does not pose any significant concern with respect to currently regulated chemical contaminants, with
the possible exception of elevated manganese concentrations occasionally found in the Haller well field.
Except for very occasional episodes of manganese particulates in parts of the distribution system, the
City consistently meets current regulations for contaminants in finished water. As mentioned earlier,
Arlington’s Haller well field is currently in Bin 1, which indicates that the City is not required to provide
any additional treatment for cryptosporidium.
4.3.1 Primary Inorganic Compounds
Figure 4-1 presents a summary graph comparing current regulations for primary inorganic compounds
and their peak concentrations observed in the City’s water sources. MCL values are shown alongside
peak values found for the Haller well field and Airport well sources. All data reported in this figure
indicate that both of the City’s water sources are well within regulatory compliance for regulated primary
inorganic constituents.
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Figure 4-1. Inorganic compound concentrations in raw water
0.006 0.01
2
0.004
0.005
0.1
1.3
0.2
4
0.015
0.002
0.1
10
1
0.05
20
0.002
ND ND
0.013
ND ND ND
0.032
ND ND ND ND ND
ND
ND ND
7
NDND
0.002
0.007
ND ND ND
0.006
ND
0.28
0.002
ND ND
1.2
ND ND
ND
ND
0.0001
0.001
0.01
0.1
1
10
100
Antimony Arsenic Barium Beryllium Cadmium Chromium Copper Cyanide Fluoride Lead Mercury Nickel Nitrate Nitrite Selenium Sodium Thallium
mg
/
L
Primary Inorganics
Primary Inorganics‐Highest Concentrations Reported
Arlington Data
DOH and EPA MCL
Haller Raw Water
Airport Finished Water
ND = Non‐Dectect Result
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4.3.2 Secondary and Physical Standards
Figure 4-2 shows a plot of the peak values of secondary health standard constituents and physical
standards found in the two water sources. These parameters do not indicate any standards associated
with health concerns, but are instead mostly connected to the aesthetic properties of water. As
mentioned previously, the only parameter of concern is the elevated concentrations of manganese
occasionally found in the two water sources. These elevated values above the regulated standard can
cause the development of particulate manganese dioxide compounds in the finished water and
distribution system, leading to laundry and fixture staining, in addition to visual aesthetic concerns of red
or brown water. Although harmless, these episodes of high levels of manganese can cause a reduction
in consumer confidence in the purity of the water. These elevated values indicate that some
management strategy or form of treatment is suggested to either mitigate the entrance of manganese
into the water system or to treat it if raw water concentrations are elevated.
Another important and regulated parameter for finished water is turbidity. Currently 95 percent of all
turbidity values in finished water must be less than or equal to 0.3 NTU. The highest observed turbidity
value in the past 12 months has been 0.056 NTU, indicating that the City’s finished water easily meets
this regulated standard. Figure 4-3 shows the variations in finished turbidity from the City’s water
treatment plant and indicates that essentially all the treated water has a turbidity of less than 0.1 NTU.
Moreover, 93 percent of the turbidity samples were less than 0.03 NTU. The finished water has low
turbidity due to the effectiveness of the filtration and to the operational practices following backwash.
Filter-to-waste occurs for 45 minutes following a backwash.
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Figure 4-2. Secondary and physical standards in raw water
250
15
2
0.3
0.05
0.1
700
250
500
55.9
10
ND
0.058
0.17
ND
94.6
4.9
119
ND
10
7
0.28
ND
0.053
ND
339
16
ND
0.0001
0.001
0.01
0.1
1
10
100
1000
Chloride Color Fluoride Iron Manganese Silver Specific Conductivity
(µmhos/cm)
Sulfate Total Dissolved
Solids
Zinc
mg
/
L
Secondary and Physical Standards
Secondary and Physical Standards‐Highest Concentrations Reported
Arlington Data
DOH and EPA MCL
Haller Raw Water
Airport Finished Water
ND = Non‐Dectect Result
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Figure 4-3. Treated water turbidity at the Water Treatment Plant
4.3.3 Disinfection By-Products
Figure 4-4 shows a plot of DBPs found in the Arlington distribution system. Data presented in Figure 4-4
are maximum TTHM and HAA5 concentrations found between 2009 and 2010. This figure indicates that
the finished water is well below the current DBP standards and that no further attention to these
constituents is likely. Moreover, the peak values of total organic carbon (TOC) observed in the water
supply is 1.44 mg/L, indicative of a water source with low concentrations of organic carbon and DBP
precursor materials.
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Figure 4-4. Highest DBP concentrations in finished drinking water
4.4 Regulatory Scenarios and Their Implications
From the information presented in this section, there are few water quality concerns for the City water
supply and treatment system. The existing facilities treating water from the Haller and Airport well fields
are producing treated water that meets the current regulations, with the only present exception being the
occasional excursion of high levels of manganese found in both sources. In the case of water obtained
from the Airport well field, it is recommended that treatment facilities be included for the removal of
manganese. It is further recommended that a more detailed source water quality investigation be
performed at the Haller well field to determine specifically which well contributes the most manganese to
the raw water stream. One strategy is to use this specific well sparingly and another strategy is to modify
the existing treatment process to enhance manganese removal upstream of the filters by adding an
oxidant as far upstream of the filters as possible, while also considering raising pH levels upstream of
the filters. The frequency of high manganese concentrations in the Haller well field source appears to be
infrequent enough to suggest management of the individual well sources from the Haller well field may
be adequate to mitigate this occasional problem.
There is also always the concern of future regulatory changes that can target emerging contaminants of
concern that can pose problems. As this is an undefined concern, no concrete recommendations can be
made other than to continue monitoring water quality. The City is a co-sponsor and participant with the
US Geological Survey and the Stillaguamish Tribe in an investigative study of pharmaceuticals and
personal care products (PPCPs), wastewater treatment byproducts, and other potential endocrine
disrupting compounds (EDCs) in the Stillaguamish basin. Waters evaluated include the Stillaguamish
River and selected tributaries, and influent to and effluent from the City’s wastewater treatment facility
before and after upgrade to a membrane bioreactor process. The results from this study were not
available during the production of this report.
60
80
22.7
40.6
1
10
100
HAA5 (µg/l) TTHM (µg/L)
Co
n
c
e
n
t
r
a
t
i
o
n
(µ
g
/
L
)
EPA and DOH MCL
Arlington Finished Water
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There is always a potential concern of groundwater contamination at the Airport well field from
commercial and industrial activity up-gradient of the well field. In this instance, continued monitoring and
enforcement of proper land use and best hazardous material practices are recommended.
In summary, the Airport and Haller well field sources appear to provide high-quality water that can easily
be treated to meet all current and anticipated future regulatory requirements.
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Section 5
Facilities Evaluation
To meet the future needs of the City, some or all of the existing water supplies (Haller well field, WTP,
Airport well, and PUD connection) must be upgraded and expanded incrementally to meet
anticipated future growth and demand in a manner most consistent with the objectives introduced in
Section 1.
This section describes the process that the City used to select the water supply alternatives for the
expansion of its water supply.
5.1 Overview of Business Case Evaluation Process
To facilitate an informed and sustainable decision on how the water supply sources should be
expanded, the program team used the BCE process. This process included a two-workshop approach
with BC staff and the City’s expert panel to gain consensus on selection of the most appropriate
water supply alternatives and their sequence for implementation for facilities expansion. The
objective of the BCE process was to select supply alternatives that meet the water demand and
quality objectives of the City at the least life-cycle cost of ownership while accounting for societal and
environmental impacts.
The key steps of the BCE process are illustrated in Figure 5-1.
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Step 8
Determine preferred solution
Step 7
Undertake net present value analysis
Step 6
Monetize environmental and community criteria
Step 5
Collect data on costs and benefits: economic, environmental,
and community risks and opportunities
Step 4
Brainstorm alternatives and screen fatal flaws
Step 3
Define evaluation boundaries; link to LOS/community values
Step 2
Document problem linked to level of service (LOS)
Step 1
Form Expert Panel: sponsor staff
Figure 5-1. BCE process overview
5.2 Selection of Expert Panel
Prior to the first workshop meeting, the City selected several members of its staff to serve as Expert
Panel members due to their familiarity with the project and the City’s future needs. The Expert Panel
members are listed below:
Jim Kelly, Public Works Director
Don Smith, Water Utility Supervisor
Bill Cochinella, Water Treatment Plant Operator
Dallas Speed, Water Treatment Plant Operator
Mike Wolanek, Water Resources Planner
The Expert Panel was responsible for evaluating supply alternatives and providing input on costs,
water quality, and public health benefits, as well as triple-bottom-line impacts associated with the
societal, economic, and environmental elements of water treatment and supply alternatives.
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5.3 BCE Workshop 1
BCE Workshop 1 was conducted on September 2, 2010, to introduce the basic BCE approach to the
Expert Panel and to incorporate Steps 1 through 4 as shown on Figure 5-1. Notes from the meeting
are included in Appendix E.
5.3.1 Determine Level of Service
The main objective of Workshop 1 was to establish potential water supply and quality objectives and
a list of water supply expansion alternatives for further evaluation.
The City determined the following level of service objectives during Workshop 1:
Capacity: The water supply expansion scenarios must justifiably meet the water demand
forecasts identified in the current City Water System Plan (refer to Table 3-3). The current
peak capacity of the existing water supply options are as follows:
o Haller well field and WTP: 1,500 gpm
o Airport well: 200 gpm
o PUD connection: 1,000 gpm
Water rights utilization: To the extent that water sources may accommodate increases in
withdrawals, and that they meet economic and other objectives, preference was given to:
o fully utilizing the City’s existing water rights at both the Haller and Airport well fields,
including the PSPL water right
o purchase and transfer of others’ existing water rights to the respective well field
o development of the City’s application for new water rights at the Airport well field
Water demand profile: Key water demand profile characteristics and utility goals for
subsequent alternatives analysis were based on the latest Water System Plan (as described
in Section 3) and are as follows:
o annual average per capita consumption: 87 gpcd
o ratio of maximum day demand to average day demand (MDD/ADD): 2.0
o ratio of peak hour demand to maximum day demand (PHD/MDD): 1.8 (met by use of
equalizing storage)
o Distribution System Losses (DSL): less than 10 percent of annual water production
o Water Use Efficiency (WUE): Reduce per capita demand by 2 percent by 2014, and 5
percent by 2028 (on target with similar goals since 2002)
Quality: One objective of the BCE process is to determine the quality of the treated water
considering current and future regulatory conditions. Current water quality treatment
difficulties at the Haller WTP and the Airport well are described in detail in Section 4. The
water quality and treatment objectives were defined as follows:
o Proactively treat for taste, odor, and color.
o Remove iron and manganese from the Airport well field.
o Provide manganese removal strategies for dealing with low but troublesome
concentrations of manganese in the Haller well field supply.
o Keep treated water DBPs at all distribution system locations below 40 µg/L for TTHMs
and 30 µg/L for haloacetic acids. These values are half of the currently regulated MCLs.
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Cost: The various permutations and combinations of water supply alternatives are to be
staged and sequenced incrementally to minimize life-cycle costs to the City while also
maximizing the City’s ability to gain additional City-owned water rights. A minimum supply of
220 gpm of PUD water is to be considered in all cost alternatives to ensure adequate
pressure to feed the City’s high pressure zones.
Timing: The expanded supply facilities are to be implemented in advance of the MDD
projections shown in Figure 3-1.
Environmental leadership: The City intends to develop water supply solutions in the most
sustainable manner. It integrates management of its water, wastewater and stormwater
utilities to assure the smallest environmental footprint that is economically viable. Water
supply alternatives preferred through the BCE process are those that:
o Exercise stewardship of limited water resources amid competing demands and multiple
beneficial uses across the Stillaguamish, Quilceda, and Sultan basins.
o Prefer long-term sustainability of water supplies for the City and the Stillaguamish River.
o Allow redundancy of water sources to assure opportunity to adaptively manage water
supplies in response to variable and unforeseen environmental demands on water
quantity (drought, flooding, minimum instream flows, water table fluctuations), water
quality (contamination events up-gradient of water sources, restoration of impaired river
water quality, management of treated effluent), and aquatic populations (fish passage,
salmon and shellfish recovery).
o Offer appropriate mitigation of impacts associated with selected alternatives.
5.3.2 Brainstorm Alternatives and Initial Screening
The Expert Panel discussed a range of supply and treatment alternatives that could be implemented
by the City. Upon discussion of the nature of these alternatives and their advantages and
disadvantages, several discrete alternatives were selected for further analysis. A complete
description of all alternatives discussed and their subsequent advantages and disadvantages are
shown in Appendix E.
During the workshop, there was discussion about expanding the Haller WTP with packaged sand
filtration equipment versus membrane filters. A summary comparing sand filtration against
membrane filtration is shown in Figure 5-2, where scenarios of building a new membrane plant and
converting the existing plant to membranes is compared to expansion of the existing sand filtration
process. Sand filtration is less costly and consumes less energy than membrane treatment. The
preliminary net present value (NPV) cost estimates to expand the Haller WTP and well field to 2,500
gpm were approximately $13.5M using membranes and $11.2M using sand filtration. The Expert
Panel selected sand filtration for all Haller WTP expansion alternatives because the panel members
did not believe that the benefits of membrane filtration outweighed the extra costs.
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Figure 5-2. Comparison of Haller WTP expansion alternatives
The discrete water supply alternatives selected for further analysis at the end of BCE Workshop 1 are
in Table 5-1.
Table 5-1. Discrete Water Supply Alternatives
Alternative Discrete Water Supply Alternative Description
1 Do nothing: 1,500 gpm (Haller WTP)+ 200 gpm (Airport well) +1,000 gpm (PUD connection)
2 Restore and upgrade Haller well field and WTP to maximum 1,835 gpm peak capacity
3 Restore Airport well field to original 580 gpm peak capacity without treatment for iron and manganese
4 Restore Airport well field to original 580 gpm peak capacity with treatment for iron and manganese
5 Increase Haller well field and WTP peak capacity to 2,500 gpm with packaged gravity media filtration
6 Increase Haller well field and WTP peak capacity to 4,369 gpm with packaged gravity media filtration
7 Increase the peak capacity at the Airport well field to 1,480 gpm with treatment for iron and manganese
8 Increase the peak capacity at the Airport well field to 1,700 gpm with treatment for iron and manganese
9 Increase peak PUD purchase to 3,000 gpm
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A detailed description of each alternative is described below:
1. Do nothing: 1,500 gpm (Haller WTP)+ 200 gpm (Airport well) +1,000 gpm (PUD connection)
Represents the existing capacity of each water supply.
2. Restore and upgrade Haller well field and WTP to maximum 1,835 gpm peak capacity
The Haller well field and WTP capacity is increased from 1,500 gpm to 1,835 gpm
through Well 3 redevelopment and improvements to reduce air binding in the finished
water pump piping.
3. Restore Airport well field to original 580 gpm peak capacity without treatment for iron and
manganese
Restore Airport well from 200 gpm to 580 gpm by drilling new well and building new
pump house.
This alternative is used to illustrate the cost impacts of treatment, since treatment has
not been employed in the past, but will be required for any future upgrades.
4. Restore Airport well field to original 580 gpm peak capacity with treatment for iron and
manganese
Restore Airport well from 200 gpm to 580 gpm by drilling new well, building new pump
house, and providing iron and manganese treatment using greensand filtration.
5. Increase Haller well field and WTP peak capacity to 2,500 gpm with packaged gravity media
filtration
Capacity of Haller well field increased with additional of new shallow well including
associated equipment and structures.
WTP capacity is increased from 1,835 gpm to 2,500 gpm through the addition of a new
building (expandable for future upgrades) comprised of similar treatment facilities as
existing operations.
6. Increase Haller well field and WTP peak capacity to 4,369 gpm with packaged gravity media
filtration
Increase capacity of Haller well field from 2,500 gpm to 4,369 gpm through addition of
new Ranney-type collector.
Increase capacity of WTP by adding addition gravity sand media filters and expanding
building.
7. Increase the peak capacity at the Airport well field to 1,480 gpm with treatment for iron and
manganese
Increase existing Airport well field capacity from 200 gpm to 1,480 gpm through addition
of three new deep treatment wells and associated pump houses with greensand media
treatment for iron and manganese.
8. Increase the peak capacity at the Airport well field to 1,700 gpm with treatment for iron and
manganese
Increase existing Airport well field capacity from 200 gpm to 1,700 gpm through addition
of four new deep treatment wells and associated pump houses with greensand media
treatment for iron and manganese.
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9. Increase peak PUD purchase to 3,000 gpm
PUD agreement increased from 1,000 gpm to 3,000 gpm
These selected discrete water supply alternatives reflect a series of interactive changes during the
BCE workshop process and subsequent discussions.
5.3.3 Risk Discussion
A discussion was held on the relative risk for each discrete water supply alternative. The risks
determined by the Expert Panel are illustrated in Table 5-2. These risk factors are subsequently
evaluated more thoroughly in BCE Workshop 2.
Table 5.2. Potential Risks with Water Supply Alternatives
Water Supply Options Potential Risks
Haller well field and WTP Difficulty in physically siting additional wells in the Haller well field (a City park)
Potential high manganese concentrations in raw water source
Potential concerns for contamination of the Stillaguamish River affecting Haller well field
Occasional elevated turbidity in the Stillaguamish River
Potential for climate change affecting Haller well field yield
Energy costs associated with pumping for distribution
Constraints imposed by environmental regulations in the Stillaguamish basin
Requires recognition and validation of existing water rights by the State; acquisition of additional water rights
Airport well field Elevated concentrations of iron and manganese will likely require treatment
Potential concerns for upgradient industrial contamination in unconfined aquifer
Energy costs associated with pumping for distribution
Constraints imposed by environmental regulations in the Stillaguamish and Quilceda basins
Requires acquisition of new and existing water rights to make full use of water source
PUD Connection No control of increase in the unit cost of water
Constraints imposed by environmental regulations in the Sultan and Snohomish basins
Requires acquisition of new water rights by the City of Everett; probable pass-through of costs
The alternatives analyses performed in this document account for these risks by including cost
factors, where feasible, to mitigate these impacts. For example, water quality concerns about iron
and manganese are mitigated by including costs for treatment. A cost escalation factor of 8 percent
annually is apportioned to the PUD connection to account for unit cost increases. Moreover, it is also
recognized that multiple sources of supply provide an added layer of system redundancy and
reliability in the event of a water supply outage. This benefit offsets any added complexity of
operating and maintaining multiple water supply systems.
5.4 BCE Workshop 2 Preparation
In preparation for BCE Workshop 2, the capital and O&M costs for water and supply alternatives
identified above were developed to determine an NPV for each alternative.
The following information was developed for each discrete alternative listed in Table 5-1 above:
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capital costs
O&M costs that included refurbishment and replacement
NPV based on 6 percent discount rate and 3 percent escalation
annual quantity of water produced
unit cost of treated water per ccf
Development of capital and operating costs for each of these discrete water supply alternatives was
based on a flow proportional blend of actual costs incurred by the City for construction and operation
of their existing facilities plus recent bid prices and operating costs for other similar plants in
Western Washington.
Capital cost estimates included the markups for construction as shown in Table 5-3. Capital costs
estimated from previously constructed projects were escalated to 2010 dollars using the Seattle
August 2010 Engineering News-Record (ENR) Index.
Table 5-3. Capital Cost Estimating Markups
Site work/yard piping 5%
Electrical/I&C upgrades 15%
Contingency (percent of construction): 30%
General conditions 10%
Contractor overhead and profit 15%
Engineering, legal, and administration (percent of construction) 30%
Sales tax 8.6%
For the capital costs of the discrete alternatives associated with the expansion of the Haller WTP to
2,500 gpm or 4,369 gpm, the cost of a new building and a new Ranney-type collector well were
included. All discrete alternatives for the Airport well field assumed that new wells would be drilled,
the existing pumps and sodium hypochlorite system would be replaced, and new greensand treat-
ment with potassium permanganate would be used to remove iron and manganese from the
groundwater. The capital cost to increase the PUD water supply from 1,000 gpm to 3,000 gpm is
based on the 2007 System Analysis and Capital Improvement Report as demonstrated in Section
2.5.2.
For Discrete Alternatives 3 through 9 identified in BCE Workshop 1 (Table 5-1), the capital costs were
distributed from 2011 to 2014 as shown in Table 5-4.
Table 5-4. Distribution of Capital Costs
Allocation of Capital Cost Percentage of Total Capital Cost
2011 - Year 1 (Predesign and Engineering) 10%
2012 - Year 2 (Engineering and Construction) 10%
2013 - Year 3 (Construction) 40%
2014 - Year 4 (Construction) 40%
Operation costs begin in 2015. Operating costs for PUD alternatives were based on the current water
rate of $1.33 per 100 cubic feet and increased at 3 percent per year.
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Table 5-5 summarizes the distribution of the existing water supply usage based on the 2009 City of
Arlington Annual Water Quality Report. The O&M cost estimates for Haller and airport water supply
alternatives were based on existing operational costs (shown in Appendix F), escalated based on
flow, and the following assumptions shown in Table 5-6. Additional maintenance was calculated for
each alternative based on 1 percent of the capital cost. Each discrete alternative’s O&M cost
estimate was based on an average annual flow rate calculated by dividing the peak capacity of that
discrete alternative by 2.0 (equaling the ratio of MDD to ADD).
Table 5-5. 2009 Water Use Profilea
Supply Percentage of Use Water Production, ac-feet/year 2009
Haller WTP 61% 936
PUD 36% 552
Airport well 3% 46
Total 100% 1,535
a. The water use profile is based on the 2009 City of Arlington Annual Water Quality Report.
Table 5-6. Operations and Maintenance Cost Assumptions
Power
Pump discharge pressure, psig 80
Pump efficiency 0.75
Motor efficiency 0.95
Cost per kW ($/kWh) $0.10
Hypochlorite
Average dosage (mg/L) 1
Sodium hypochlorite ($/gal) $1.00
Potassium permanganate (for iron and manganese oxidation)
Average dosage (mg/L) 1.5
Potassium permanganate ($/pound) $3.80
Maintenance
Maintenance cost as percentage of capital cost 1%
Labor
Labor cost ($/hr) $40
PUD
Escalation 8%
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5.5 BCE Workshop 2 and Evaluation of Final Alternatives
The second BCE Workshop was conducted on October 22, 2010. Workshop 2 completed steps 5–8 of
the BCE process, as shown on Figure 5-1. Workshop 2 served the following functions:
discuss and assess risk factors for each of the discrete water supply alternatives
review and validate the life-cycle cost estimates developed for each discrete water supply
alternative developed in preparation of BCE Workshop 2
revise life-cycle cost estimates for the updated discrete water supply alternatives
calculate life-cycle cost estimates for combinations of discrete water supply alternatives to
determine appropriate timing for implementation of each discrete alternative at the lowest life-
cycle cost
develop a set of recommended discrete water supply projects that can be phased over time to
meet forecasted water demands.
5.5.1 Environmental Risks and Opportunities of Water Supply Alternatives
The risks identified during Workshop 1 were evaluated during Workshop 2. Each risk was giving a weight
between zero and five where five represents a risk that could highly impact a water supply alternative. A
zero was giving for a risk that was mentioned, but then determined not to be important in this analysis.
The risks were also weighted on a scale from zero through five with five being the highest risk. A zero
risk value means that the risk was determined not to be applicable to the water supply alternative. The
total risk score is the summation of the product of the weight and the risk value for each category.
The results of the risk analysis during Workshop 2 are shown in Table 5-7. The PUD supply has the
lowest risk at a score of 98. This is largely due to the risk element labeled “political”, which includes
issues with obtaining water rights. If water rights were easily obtained and the political section is
removed from the analysis, the risk score for Haller, Airport, and PUD supplies becomes 84, 72, and 80,
respectively; the Airport supply alternative has the lowest risk. The risks presented in Table 5-7 were not
monetized in the life cycle cost analysis.
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Table 5-7. Analysis of Potential Risks of Water Supply Alternatives
Weight (0-5) Haller Airport PUD
Risk Risk (1-5)
Water Quality
Manganese Treatment (possibly Fe) 3 2 4 1
Vulnerability 3 4 3 1
Unknown water quality in new wells or source 2 2 4 1
Lack of control 0 1 1 1
Economic
O&M Challenges 1 2 1 1
Drastically Increase O&M Costs 3 2 2 5
Increased Capital Costs 4 2 2 5
Constructability (new wells in new locations) 2 3 2 1
Environmental
Less Susceptible to Climate Change 3 4 2 3
Energy and Chemical Usage 2 3 2 3
Other regulatory impacts 3 4 2 4
Political
May not obtain water right 5 4 4 1
Difficult permitting process 4 2 3 1
Water right impairment mitigation 2 2 3 1
Sunset on PUD contract; potential loss of PUD water 3 0 0 3
Social
Limited Supply for Demand 3 1 1 1
Well location impact 2 3 2 1
TOTAL RISK SCORE (sum of product of weight and risk) 115 109 98
5.5.2 Life-Cycle Costs of Discrete Alternatives
For the discrete water supply alternatives shown in Table 5-1, life-cycle cost information was developed.
A summary of the cost analysis for these alternatives is shown in Table 5-8.
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Table 5-8. 20 Year Life-Cycle Cost Analysis for Discrete Water Supply Alternatives
City of Arlington
Evaluation of Discrete Water Supply Alternatives
Workshop No. 2 - Alternatives Net Present Value Analysis
Agency: City of Arlington Results
Project/Problem:
Evaluation of Discrete Water Supply Alternatives Capital Cost1 NPV2 Difference Annualized
Cost, $/year
Annual
Incremental
Water
Incremental
Unit Cost of
Water,
Alternative
1A Do Nothing-1,500 gpm (Haller)($7,011,489) ($6,388,245)$471,000 527,005 $0.89
1B Do Nothing-200 gpm (Airport)($623,243)$42,000 70,267 $0.60
1C Do Nothing-1,000 gpm (PUD)($9,154,687) ($8,531,444)$615,000 351,337 $1.75
2 Restore and Upgrade Haller Wellfield and WTP to1,835 gpm peak capacity $553,860 ($2,002,634) ($1,379,391)$135,000 117,698 $1.15
3 Restore Airport Well to 580 gpm without Fe/Mn Treatment $974,142 ($2,289,392) ($1,666,149)$154,000 203,775 $0.76
4 Restore Airport Well to 580 gpm with Fe/Mn Treatment $2,345,760 ($3,913,114) ($3,289,870)$263,000 203,775 $1.29
5 Increase Haller Wellfield and WTP Capacity to 2,500 gpm-Packaged Gravity Media Filtration $4,430,880 ($7,568,512) ($6,945,269)$509,000 351,337 $1.45
6
Increase Haller Wellfield and WTP Capacity to 4,369 gpm (from 2,500 gpm) - Packaged
Gravity Media Filtration $12,239,220 ($13,827,776) ($13,204,533)$929,000 656,649 $1.41
7 Increase Airport Well Field Capacity to 1,480 gpm with Fe/MnTreatment $5,364,840 ($9,446,154) ($8,822,910)$635,000 523,492 $1.21
8 Increase Airport Well Field Capacity to 1,700 gpm with Fe/Mn Treatment $6,059,880 ($10,723,026) ($10,099,783)$721,000 597,273 $1.21
9 PUD Purchase for 3,000 gpm $13,501,870 ($43,432,286) ($42,809,042)$2,919,000 1,054,011 $2.77
Year of analysis: 2010
Escalation rate: 3.00%
Discount rate: 6.00%
1 Capital costs are based on 2010 dollars.
2 O&M costs are assumed to begin in the year 2015.
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Table 5-8 shows that in general, alternatives related to restoration of existing supply assets are the best
investment for the City. Following that, alternatives to further the development of groundwater supply
resources at the Airport well field are the next-least expensive on a unit cost of water basis, closely
followed by alternatives to further develop the Haller well field supply source. The PUD supply source
costs are considerably higher than those of the other supply source alternatives because of the large
capital investment required within the PUD distribution system.
5.5.3 Life-Cycle Costs for Combinations of Discrete Alternatives
During BCE Workshop 2, a few improvements that could be made to the discrete alternatives’ life-cycle
cost estimates were discussed. The NPV costs in Table 5-8 assume that the O&M costs will be the same
over the 20-year life span of the analysis. For example, the O&M costs for Alternative 5 assumes a flow
rate of approximately 1,250 gpm from 2010 to 2030 regardless of demand. This same method was
used for all alternatives, so they are comparative. The labor cost estimates for the discrete alternatives
are based on increasing current operations costs proportionally to the increase in additional flow.
The capital costs for Alternatives 3 through 9 begin in the same year. This method does not allow an
estimating of cost for combining discrete alternatives.
In order to get a better idea of the NPV for a combination of discrete alternatives, the cost analysis was
redone for a few combinations of discrete alternatives. This follow-on analysis also selected the timing
for implementing a water supply expansion alternative by evaluating which year the improvement will
give the lowest NPV. The result of this cost analysis for four combinations of discrete alternatives is
shown in Table 5-9. Based on Table 5-8, the Expert Panel recommended that all of the combinations of
discrete alternatives include Alternative 2 (restore and upgrade Haller well field and WTP to maximum of
1,835 gpm in 2011). The capital cost is incurred in 2011 and it is assumed that the plant will operate
with the improvements in 2012. Haller operating costs subsequently increase in 2012.
The difference in calculating the NPV for combinations of discrete alternatives is that the implementation
of the discrete alternatives is based on water demand and timing to achieve the lowest NPV. It was
decided in BCE Workshop 2 that the City of Arlington supply alternatives should be upgraded
preferentially before upgrading the PUD to 3,000 gpm (Discrete Alternative 9). Therefore, the City must
upgrade the Haller or Airport water supplies to meet the MDD before being required to purchase more
than 1,000 gpm of PUD water. The difference in the MDD minus the current City’s capacity was fulfilled
using PUD water.
During Workshop 2, it was determined that the City requires a minimum of 220 gpm of PUD connection
water to serve the high elevation water system customers in the 710 and other upper system pressure
zones without resorting to more energy intensive pumped water supply. If the difference between the
MDD minus the City’s current capacity was less than 220 gpm, 220 gpm was used in the O&M
calculations. The O&M costs in Table 5-9 never assume less than 220 gpm of PUD water.
Labor costs were estimated based on full-time equivalents. An hourly rate of $40 was used to estimate
annual labor costs. An additional FTE was assumed for upgrading the Airport well field to 1,490 gpm. An
additional FTE was also assumed for upgrading Haller to 2,500 gpm.
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Table 5-9. 20 Year Life-Cycle Cost Analysis for Combinations of Discrete Water Supply Alternatives
City of Arlington
Evaluation of Combinations of Discrete Alternatives1
Combinations Net Present Value Analysis
Agency: City of Arlington Results3
Project/Problem:
Evaluation of Combinations of Discrete Alternatives1 Capital Cost2 NPV Difference Annualized Cost,
$/year
Combination 1 Upgrade Aiport Well Field to 1490 gpm in 2015 $5,918,700 ($20,129,283) ($4,376,702)$1,353,000
Combination 2 Upgrade Aiport Well Field to 1490 gpm in 2020 $5,918,700 ($18,661,012) ($2,908,431)$1,254,000
Combination 3 Upgrade Aiport Well Field to 1490 gpm in 2018 and 1700 gpm in 2025 $6,982,980 ($15,752,581)$1,059,000
Combination 4
Upgrade Haller Well Field and WTP to 2,500 gpm in 2018 Upgrade Airport Well
Field to 1,480 gpm in 2025 $10,349,580 ($19,493,277) ($3,740,696)$1,310,000
Year of analysis: 2010
Escalation rate: 3.00%
Discount rate: 6.00%
Notes:
1 All combinations include restore and upgrade Haller Wellfield and WTP to maximum of 1,835 gpm in 2011.
2 The capital costs are based on 2010 dollars but implemented throughout the 20 year time span of the life cycle analysis.
3 These results do not include a comparison of capacity and unit costs because each alternative has the same water usage
based on the projected water demand.
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The difference between Combinations 1 and 2 in NPVs is approximately $1.5M. This difference is based
on when Discrete Alternative 7 (upgrade Airport well field to 1,480 gpm with Fe/Mn treatment) is
implemented and reflects the time value of money. The timing of the implementation of the discrete
alternative affects the NPV. These combinations of discrete alternatives were evaluated through 2030.
Combination 3 has the lowest NPV by approximately $2.9M.
5.6 Recommended Plan
Based on the information shown in Table 5-9, a recommended plan linked to the water demand forecast
(Figure 3-1) was developed. Various combinations of the discrete water supply projects were evaluated
as a function of time to determine the optimal combinations that produced the lowest cost to the City at
any given time as shown in Table 5-9. Combination 3 had the lowest NPV. It is recommended that the
City implement Combination 3. A composite chart illustrating these optimal specific projects and their
timing relative to water demand forecasts is shown in Figure 5-3. Note that new capacity is brought
online somewhat in advance of the projected demand for two basic reasons:
The proposed project schedule achieves the lowest overall NPV value.
It also allows for a safety factor in terms of uncertainties in forecasted demand.
Water Supply Alternatives Feasibility Report Section 5
5-16
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0
1,000
2,000
3,000
4,000
5,000
6,000
7,000
2010 2015 2020 2025 2030 2035
Ca
p
a
c
i
t
y
(g
p
m
)
MDD Projection (gpm)Existing Condition Restore Haller to 1835 gpm
Upgrade Airport to 1490 gpm Upgrade Airport to 1700 gpm
ExistingCondition
Water Supply Capacity
Haller ‐1,500 gpm
Airport ‐200 gpm
PUD ‐1,000 gpm
Water Rights
GWC 5169 + Existing Airport
Restore Haller
Design and Construction: 2011
Operational: 2012
Water Supply Capacities
Haller ‐1,835 gpm
Airport ‐200 gpm
PUD ‐1,000 gpm
Water Rights
GWC 5169 + Existing Airport +
Klein
Upgrade Airport
Design: 2015/2016
Construction: 2017/2018
Operational: 2018
Water Supply Capacities
Haller ‐1,835 gpm
Airport ‐1,480 gpm
PUD ‐1,000 gpm
Water Rights
GWC 5169 + Existing Airport +
Klein+ Application G1 ‐26641
Upgrade Airport
Design: 2024
Construction: 2025
Operational: 2025
Water Supply Capacities
Haller ‐1,835 gpm
Airport ‐1,700 gpm
PUD ‐1,000 gpm
Water Rights
GWC 5169 + Existing Airport + Klein+
Application G1‐26641+National Food
Corporation+Turf Farm
Figure 5-3. Recommended discrete water supply project timing
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A summary of the recommended plan and the timing of specific discrete water supply projects is shown
in Table 5-10.
Table 5-10. Recommend Water Supply Plan
Discrete Water Supply Project Year for Project to be
Operational
Total Project Cost: August
2010$
Restore and upgrade peak capacity of the Haller well
field and WTP from 1,500 gpm to 1,835 gpm
2013 $560,000
Install new peak water supply and treatment capability
at the Airport well field from 200 gpm to 1,480 gpm
2018 $5,360,000
Install new peak water supply and treatment capability
at the Airport well field from 1,480 gpm to 1,700 gpm
2025 $1,065,000
Implementation of these projects requires acquisition of specific water rights, as shown in Figure 5-3 and
described in Section 3. If, for example, the Airport well field water rights are not acquired to meet the
schedule shown in Table 5-10, other projects, namely the expansion of the Haller well field and WTP,
would take precedence, assuming that the additional PSPL water rights associated with the Haller
system can be acquired in a timely fashion.
Additionally, the PUD connection water supply (up to 1,000 gpm) will still be required to supplement the
City’s own water supply capacity to make up for any shortfalls in water demand. These recommended
projects minimize the use of the more expensive PUD connection. The largest requirement of PUD water
is estimated at approximately 650 gpm in 2017, based on MDD. A minimum of 220 gpm of PUD
connection water was used in this analysis.
Another factor that can affect the recommended sequencing of these discrete water supply projects
relates to the year in which they are implemented. The recommended project sequence is based on
specific projects implemented at specific years as identified in Table 5-10. If there is a delay in obtaining
a particular water right or if forecasted demand changes, project timing will shift. Due to the time value
of money, shifting the implementation schedule on these projects can alter the selection of the overall
least-cost project sequence. For example, a delay on implementing the third project identified in Table 5-
5 (increasing the Airport well field supply from 1,480 gpm to 1,700 gpm) could cause the Haller well field
and WTP project to increase its capacity from 1,835 gpm to 2,500 to become the next least-cost project.
Validation of preferred project sequencing will need to be conducted in the future as actual events take
place.
Combination 3 was determined to be the most effective water supply solution to meet the City’s water
demands through 2030. Beyond the 2030 year time frame, other projects to increase the City’s water
supply capacity will require incremental capacity increases at the Haller well field and WTP. Construction
of a large capital project cost ($13,500,000) to increase the PUD connection capacity to 3,000 gpm is
not recommended because of the very high unit cost of water resulting from this alternative.
REF-1
Final Arlington Feasibility Report.docx
References
Arlington Water Treatment Plant KEY-PAC AC-1710-3 Process Description, 1–7.
Fraser D. and Fraser, D. Results of the Comprehensive Performance Evaluation of Arlington Water Treatment Plant:
Haller Well Field. The Cadmus Group, Inc. 2003.
Disinfection Profiling and Benchmarking. Environmental Protection Agency. 1991. Available from
http://www.epa.gov/ogwdw000/mdbp/pdf/profile/benchpt1.pdf
AWWARF. AWWARF Featured Topic: EDCs, PhACs and PCPs. 2005. Available from
http://www.waterresearchfoundation.org/research/TopicsAndProjects/topicSnapShot.aspx?Topic=EDCS
Shaw, J., Cotton, C, Chowdhury, Z. and Archibald, E. Planning for Compliance: An Evaluation of Water Quality Conditions
that could Trigger the Need for Treatment Changes. In Proceedings of American Water Works Association Water
Quality Technology Conference. Seattle, Wash. 2009.
Appendix A: Assessment of Water Supply Alternatives
206.329.0141 F 206.329.6968 | 2377 Eastlake Avenue East | Seattle, Washington 98102 | www.pgwg.com
Water Resource & Environmental Consulting
Technical Memorandum
To: Matt Marring, Brown and Caldwell
From: Dan Matlock and Jeff Parker, Pacific Groundwater Group
Re: Phase 1: Water Supply Alternatives Feasibility Report
Date: January 4, 2011
This technical memo presents an assessment of water supply alternatives for the City of
Arlington Haller Park Wellfield and Airport Supply Area. Included in the assessment for
each supply area is a summary of current production capabilities and recommendations
for increasing future water supply. The assessment is based on water supply options laid
out in the revised Water System Plan (Matt Maring, Personal Communication). Haller
Park improvements include restoration of capacity to 1,710-1,835 gallons per minute
(gpm), expansion to 2,500 gpm, and expansion to the full wellfield water rights of 4,079
gpm. The Airport improvements include restoration of capacity to 580 gpm, and expan-
sion to 1,480 gpm or 1,700 gpm.
HYDROGEOLOGIC UNITS
This section provides brief descriptions for each of the hydrogeologic units that are in the
vicinity of the Haller Park Wellfield and the Airport Well (PGG, 2007).
Alluvium (Qal) typically consists of silty to clean sand and gravel with cobbles and
boulders with some wood and organics, which were deposited by the mainstem of the
Stillaguamish. In the Haller Park Wellfield this unit is difficult to distinguish from any
underlying Vashon Recessional Outwash (Qvr) deposits. In the Haller Park Wellfield,
Qal and Qvr deposits create a single aquifer. The alluvial thickness in the Haller Park
Wellfield is about 35 feet at Well 1R, but may be deeper depending on the local bedrock
configuration.
Vashon Recessional Outwash (Qvr) was deposited as the Vashon ice sheet receeded at
the end of the last ice age. The deposits typically consist of loose, silty to clean sand and
gravel without appreciable organics, comprising several mappable units. The thickness of
the Qvr is up to 130 feet. At the Airport Well, Qvr is 103 feet thick, whereas at the Air-
port Test Well (93-10) it is 64 feet thick.
Vashon till (Qvt) was deposited beneath the advancing Vashon ice sheet. The deposits
typically consist of an unsorted mixture of dense to very dense gray to brownish gray,
City of Arlington Water Supply Alternatives 2
JANUARY 4, 2011
gravelly silty sand, which is often referred to as “hardpan” in driller’s logs. The Qvt is
largely absent from the Marysville Trough lowlands, where the Airport Well is located,
but as much as 100 feet thick on the Getchel Plateau uplands, east of the Airport Well and
southeast of Arlington. This unit is considered an aquitard.
Vashon Advance Outwash (Qva) was deposited in front of the advancing Vashon ice
sheet. The deposit typically consists of a coarsening upward sequence of dense, brown,
silty to clean fine to medium sand with some gravel. The Qva is up to 200 feet thick be-
neath the uplands, but thinner in the lowlands. The Qva is about 100 feet thick at the Air-
port Well.
Quaternary Transitional Beds (Qtb) were deposited in a pro-glacial lake formed during
the advance of the Vashon ice sheet. The deposits typically consist of fine-grained silts
and clays, with occasional interbeds of sand and pea gravel. This unit is considered an
aquitard.
Bedrock is an important aquitard that delimits the thickness and extent of groundwater
supplies for Arlington. Depth to bedrock is 35 feet at Haller Park Well 1R, but as much
as 300 feet at the Airport Well.
HALLER PARK WELL FIELD
The Haller Park Wellfield is located just downstream of the confluence of the North and
South Forks of the Stillaguamish River. The wellfield consist of three shallow wells,
Well 1R, Well 2, and Well 3 completed in Qal or Qal/Qvr deposits. Well construction
details are presented in Table 1. Well 1R was installed in 2000. Well 2 was last redeve-
loped in 2000, which slightly increased its well efficiency. At the same time, Well 3 was
tested, but it was believed that redevelopment was not warranted. The construction details
of Well 3 are not documented. In 2001, Well 2 and 3 were reconfigured with new motors,
columns, pumps and well houses.
CAPACITY
The maximum operational capacity of Well 1R is 570 gpm, Well 2 is 570 gpm, and Well
3 is 1,140 gpm. In 2002, the reported specific capacity at Well 1R was 95 gpm/ft, Well 2
was 140 gpm/ft, and Well 3 was 300 gpm/ft. Specific capacity is influenced by a number
of factors such as aquifer properties, screen design, well diameter, and well maintenance.
Due to high iron and manganese, Well 1R is operated as a backup source to Wells 2 and
3. Since Well 1R is used as a backup supply, the total pumping capacity of the wellfield
is 1,710 gpm. Wellfield instantaneous water rights equal 1,835 gpm plus 2,244 gpm from
the Puget Sound Power and Light (PSPL) water right for a total of 4,079 gpm. Maximum
treatment plant inflows from combined sources Wells 2 and 3 indicate that the current
instantaneous production is less than 1,600 gpm and that the pumping capacity of 1,710
gpm cannot be met. Based on conversations with Mike Wolanek with the City of Arling-
ton one or both wells may be limiting production.
City of Arlington Water Supply Alternatives 3
JANUARY 4, 2011
AQUIFER PROPERTIES
River stage and Haller Park well water levels are highly correlated (PGG, 2002), which
suggests good hydraulic connectivity between the aquifer and the river. Pumping tests
conducted on Well 1R and Well 3 indicate the aquifer transmissivity is quite high
(700,000 gpd/ft) and that the storage coefficient is about 0.02 (PGG, 2002). At least two
12-inch diameter test wells were drilled in 1954 at Haller Park, at a distance of 95 feet
and 185 feet southwest of Well 3 (i.e. between Well 3 and the nearby parking lot). Pump-
ing test data are not available for these wells.
AQUIFER EXTENT
The alluvial aquifer at the Haller Park Wellfield occurs in a narrow band along the river.
The aquifer abuts older glacial sediments to the south of the Wellfield. Siting of new ver-
tical wells is limited by the extent of the alluvial aquifer.
DRY SEASON PUMPING LEVEL
We performed a rough assessment of dry season pumping level at Well 2 and 3 by com-
paring water level elevations and the treatment plant inflows with stream gage data col-
lected near the confluence of the South and North Forks of the Stillaguamish. The great-
est drawdown in Wells 2 and 3 would be expected to occur during low river stages when
water demand and wellfield production is the highest.
Data provided by the City of Arlington indicates that the dry season pumping water level
elevations are about 45 feet (NAVD 88) at Well 2 and about 42 feet at Well 3. These ele-
vations correspond to pumping water level depths of about 27 and 30 feet for Wells 2 and
3, respectively (assuming a measuring point elevation of 72 feet).
Assuming a pump intake setting of 31 feet for Well 2 and a minimum pump submergence
of 1.5 feet, there would be 2.5 feet of available drawdown. In a similar manner, assuming
a pump setting of 34 feet for Well 3 and a minimum pump submergence of 1.5 feet, there
would be 2.5 feet of available drawdown. It is important to note that the accuracy of these
calculations may be in error by as much as one-foot or more
INTERFERENCE DRAWDOWN
Installation of additional vertical wells at the Haller Park Wellfield would impose addi-
tional interference drawdown in Wells 2 and 3. Assuming the above listed aquifer proper-
ties for the Haller Park Wellfield, the estimated interference drawdown at Wells 2 and 3
from one additional well pumping at 800 gpm for 7 days would be as follows:
City of Arlington Water Supply Alternatives 4
JANUARY 4, 2011
New Well
Offset (ft)
Interference
Drawdown (ft)
10 2.6
30 1.9
100 1.4
WATER QUALITY
Water quality at Haller Park wells is good with the exception of iron and manganese at
Well 1R. Although the wells are completed in the same aquifer and in close proximity to
one another, there is a significantly higher concentration of iron and manganese in Well
1R relative to Wells 2 and 3. However, samples collected in 2010 indicate that manga-
nese in Wells 2 and 3 sometimes is only marginally below the secondary Maximum Con-
taminant Level (MCL).
One of the 12-inch test wells completed in 1954 is reported to have had high iron concen-
trations.
AIRPORT SUPPLY AREA
The City currently operates one supply well in vicinity of the Arlington municipal airport
which is referred to as the Airport Well. The well is located on the east side of the airport
near 59th Avenue NE. The City also installed a 6-inch test well (93-01) in 1993 approx-
imately 2,500 feet south of the Airport Well (PGG, 1993). Both wells are completed in
the Advance Outwash aquifer (Qva). Well construction details are presented in Table 1.
CAPACITY
The Airport Well, drilled in 1945, was originally known as Navy Well No. 3. The well
was rehabilitated in 2009 when a broken weld on the well screen was allowing sand to
enter the well and distribution system. A cement plug was installed to seal off a broken
portion of the lower screen section. Prior to rehabilitation, the well was able to produce
430 to 450 gpm. Following rehabilitation, the capacity dropped to about 250 gpm. Li-
mited pumping test data from 1945 suggests a specific capacity of 27 gpm/ft at the time
of construction. The current well specific capacity is approximately 3.5 gpm/ft.
Results from a constant-rate pumping test at test well 93-01 indicate an aquifer transmis-
sivity of approximately 50,000 gpd/ft. The specific capacity of Well 93-01 is approx-
imately 8.5 gpm/ft (PGG, 1993).
City of Arlington Water Supply Alternatives 5
JANUARY 4, 2011
Well testing of both the Airport Well and Well 93-01 indicates that properly designed and
constructed wells could produce between 500 and 600 gpm.
INTERFERENCE DRAWDOWN
Adding wells to the Airport supply area would result in some interference drawdown be-
tween adjacent wells. Given aquifer properties at the Airport Well and Well 93-01 and
assuming aquifer storage coefficient for a confined aquifer of 0.0001, the interference
drawdown effects from one well pumping at 500 gpm for 7 days would be as follows:
New Well
Offset (ft)
Interference
Drawdown (ft)
10 18.5
100 13.3
2,500 5.9
The Airport Well and Well 93-01 both have about 125 to 130 feet of available drawdown,
which should be sufficient to accommodate pumping rates of 500 to 600 gpm and ex-
pected interference drawdown noted above from several nearby wells.
It may be possible to locate as many as three to four supply wells in the airport vicinity
which could contribute as much as 1,700 gpm to the City’s supply system. Existing water
rights allow the City to pump up to 580 gpm from the existing Airport Well site and a
new replacement well should be installed to take advantage of these rights. Additional
water rights would need to be secured to support operation of other new supply wells in
this area. The City should seek to acquire additional rights to support expanded develop-
ment in this area.
WATER QUALITY
Water quality at the Airport Well is good. From 2005 to 2010, iron and manganese sam-
ples had concentrations below the detection limit. However, samples collected between
2001 and 2004 indicate manganese concentrations ranged from 0.022 mg/L to 0.053
mg/L, which are marginally below to slightly above the secondary MCL for manganese
of 0.05 mg/L.
The water quality reported for Well 93-01 is generally good, with the exception of man-
ganese. Manganese was measured at 0.171 mg/L, well above the secondary MCL. Iron
was measured at 0.185 mg/L, which is somewhat lower than the MCL of 0.3 mg/L.
Wells completed in the advance outwash aquifer in the Marysville Trough are potentially
susceptible to contamination from surface sources. A review of well logs for the Airport
City of Arlington Water Supply Alternatives 6
JANUARY 4, 2011
Well and Well 93-01 indicate the presence of interbedded fine-grain silt, clay, and silty
sand deposits that separate the Qvr and Qva deposits. The fine-grained deposits are ap-
proximately 14 feet thick at the Airport Well and about 60 feet thick at Well 93-01. Al-
though these deposits may reduce the hydraulic coupling of the two aquifers to some ex-
tent, the two units still appear to function as a single connected aquifer system. Ground-
water flow direction across the Airport supply area is generally to the northwest. A cur-
sory look at land use upgradient or southeast of the Airport Well suggests some potential
sources of contamination. A detailed survey should be completed to identify all potential
sources of contamination that might exist in proximity to the City’s airport well sites
prior to installing any replacement or new supply wells.
RECOMENDATIONS
HALLER PARK WELLFIELD
Wells 2 and 3 have been unable to meet the target capacity of 1,710 gpm with one or both
wells limiting production. Both wells should be tested independently with existing pumps
to assess the current specific capacity. The results would be used to recommend the ap-
propriate level of redevelopment if necessary. We anticipate that Well 3 may need rede-
velopment. If so, the well should be redeveloped during a period of low water demand.
At the time of redevelopment, when the pumps are pulled, a video log should be recorded
at Well 3.
Our assessment of dry season pumping water levels during low river stages and high de-
mand indicates that there may be 1.5 to 3.5 feet of available drawdown in Wells 2 and 3.
The accuracy of these measurements is significant for estimations of pumping impacts
from an additional well. We recommend that a licensed surveyor measure the well water
level measuring points, the Stillaguamish river gage, and the pump pedestals so that
pumping and static groundwater levels and river elevations can accurately correlated to
one another. Additionally, transducer and hand-measured water levels should be accu-
rately tied to measuring points.
Our interference analysis indicates that it may be possible to achieve a future expanded
capacity of 2,500 gpm with one additional vertical well at the site. In order to minimize
interference drawdown within the wellfield, the new well should be sited at the greatest
distance possible from existing wells, but prospective locations are limited by the narrow
extent of the alluvial aquifer. High well efficiency could be achieved with 24 to 30-inch
diameter completion. It is anticipated that the well completion depth would be approx-
imately 38 feet below ground surface. Typical well drilling costs for these specifications
would be on the order of $80,000. This would include subcontract drilling and hydrogeo-
logic support services for well design, installation, and testing. Prior to siting a new well,
we recommend a more accurate study of dry season pumping water levels, interference
drawdown, and aquifer extent.
City of Arlington Water Supply Alternatives 7
JANUARY 4, 2011
Future vertical wells may have manganese and possibly iron concentrations marginally
below or above secondary MCLs. It is recommended that water quality samples be col-
lected either during the drilling of the production well or from one or more small diame-
ter test holes.
Given current wellfield constraints, it does not appear as though the City could fully util-
ize the wellfield water rights of 4,079 gpm with vertical wells. However, a capacity of
over 4,000 gpm could likely be obtained with one Ranney-type collector. A Ranney-type
collector consists of a large diameter casing (approximately 16 feet) with lateral screens
that would extend outward into the aquifer towards the Stillaguamish River. The water
quality of each lateral screen could be isolated and tested to minimize potential manga-
nese or iron exceedences of secondary MCLs. A Ranney Collector Well representative
indicated that a collector well could be constructed for about $1,250,000 and would likely
provide sufficient capacity to fully exercise the City’s wellfield water right of 4,079 gpm.
If a Ranney-type collector was installed, the City could use their existing wells for back-
up supply during future maintenance events. This may be a preferred option for the City
future water supply in the event that new water rights could not be secured near the Air-
port Supply Area.
AIRPORT SUPPLY AREA
The new Water System Plan projects future expansion of the supply area to 1,700 gpm,
which is contingent on the acquisition of additional water rights. The City currently
holds water rights for 580 gpm and has a pending application for 900 gpm of additional
supply. To achieve a total supply of 1,700 gpm, the City would need to acquire an addi-
tional 1,120 gpm of instantaneous water rights.
We would recommend that new supply wells near the airport be designed as follows:
20-inch surface seal seated into silt/clay confining unit at about 100 feet
16-inch casing extending to the top of the Qva aquifer at about 150 feet
12-inch pipe size screen extending from about 150 to 180 feet
In order to optimize well efficiency and reduce the potential for sand production, the
well’s design should incorporate a sand pack that would surround the 12-inch screen. The
recommended surface seal is greater than the minimum standard in order to minimize the
potential for contamination from water bearing units above the production zone that are
more susceptible to contamination. The estimated cost for a new production well would
be approximately $135,000. This would include subcontract drilling and hydrogeologic
support services for well design, installation, and testing.
Additional wells could be installed in phases. It is anticipated that three to four additional
wells would be needed to achieve the target capacity of 1,700 gpm including a replace-
ment for the Airport Well. Expected well capacity, aquifer properties, and wellfield inter-
City of Arlington Water Supply Alternatives 8
JANUARY 4, 2011
ference effects should be re-evaluated after the installation and testing of the replacement
Airport Well and prior to the siting of additional new wells.
Also, when siting any and all new Airport wells, the proximity of industrial facilities, air-
port fuel storage facilities, and other sources of potential contamination that would fall
within the Well Head Protection Area should be considered since the aquifer is potential-
ly susceptible to surface contamination due to the absence of significant overlying confin-
ing layers. A cursory look at land use upgradient or southeast of the Airport Well sug-
gests some potential sources of contamination. A detailed survey should be completed to
identify all potential sources of contamination that might exist in proximity to the City’s
airport well sites prior to installing any replacement or new supply wells.
Manganese and possibly iron concentrations should be anticipated to be above or margi-
nally below secondary MCLs for any Airport supply area well. Available water quality
data are not sufficient to site or screen wells in such way to reliably achieve water quality
below the secondary MCL for iron and manganese. Iron and manganese can be effective-
ly treated with ATEC treatment systems which are used by many other water purveyors
in the area.
REFERENCES
Pacific Groundwater Group [PGG], 1993, Phase II Hydrogeologic Investigation, City of
Arlington, Consultant letter report from Pacific Groundwater Group to Barret
Consulting Group, December 15, 1993.
PGG, 2002, Construction and Testing of Replacement Well No. 1 (Well-1R), Haller Park
Wellfield, Consultant report from Pacific Groundwater Group, prepared for the
City of Arlington and EarthTech, Inc., November, 2002.
PGG, 2007, City of Arlington Hydrogeologic Conceptual Model Summary Report, Con-
sultant report from Pacific Groundwater Group, prepared for the City of Arling-
ton, January, 2007.
techmemo_arlington wellfield assessment_final.docx
JM1003
Appendix B: Disinfection Profiling and Benchmarking
Guidance Manual
Appendix C: Analysis of Precipitate
Appendix D: Summary of Federal and State Water
Quality Regulations
D-1
Final Arlington Feasibility Report.docx
Summary of Federal and State Water Quality Regulations
Recreated from the Washington State Department of Health (DOH) Group A Public water Supplies, Chapter 246-290 WAC, November 2009: http://www.doh.wa.gov/ehp/dw/publications/331-010.pdf
and the U.S. Environmental Protection Agency: http://www.epa.gov/safewater/mcl.html#mcls
Contaminant Potential Health Effects from Ingestion of Contaminant Sources of Contaminants in Drinking Water
USEPA/Washington DOH
MCLG a
(mg/L) b
MCL or TT a
(mg/L) b
Secondary
Standard
(mg/L)
Microorganisms
Cryptosporidium Gastrointestinal illness (e.g., diarrhea, vomiting, cramps) Human and animal fecal waste zero TT c
Giardia lamblia Gastrointestinal illness (e.g., diarrhea, vomiting, cramps) Human and animal fecal waste zero TT c
Heterotrophic plate count HPC has no health effects; it is an analytic method used to measure the
variety of bacteria that are common in water. The lower the concentration of
bacteria in drinking water, the better maintained the water system is.
HPC measures a range of bacteria that are naturally
present in the environment
n/a TT c
Legionella Legionnaire’s Disease, a type of pneumonia Found naturally in water; multiplies in heating systems zero TT c
Total coliforms (including fecal coliform and E. Coli) Not a health threat in itself; it is used to indicate whether other potentially
harmful bacteria may be present d
Coliforms are naturally present in the environment, as
well as in feces; fecal coliforms and E. coli only come
from human and animal fecal waste.
zero 5.0% e
Turbidity Turbidity is a measure of the cloudiness of water. It is used to indicate water
quality and filtration effectiveness (e.g., whether disease-causing organisms
are present). Higher turbidity levels are often associated with higher levels of
disease-causing microorganisms such as viruses, parasites and some
bacteria. These organisms can cause symptoms such as nausea, cramps,
diarrhea, and associated headaches.
Soil runoff n/a TT c
Viruses (enteric) Gastrointestinal illness (e.g., diarrhea, vomiting, cramps) Human and animal fecal waste zero TT3
Disinfection By-products
Bromate Increased risk of cancer By-product of drinking water disinfection zero 0.010
Chlorite Anemia; infants and young children: nervous system effects By-product of drinking water disinfection 0.8 1.0
Haloacetic acids (HAA5) Increased risk of cancer By-product of drinking water disinfection n/a f 0.060
Total trihalomethanes (TTHMs) Liver, kidney or central nervous system problems; increased risk of cancer By-product of drinking water disinfection n/a f
0.080
Disinfectants
Chloramines (as CI2) Eye/nose irritation; stomach discomfort; anemia Water additive used to control microbes MRDLG=4 a MRDL=4.0 a
Chlorine (as CI2) Eye/nose irritation; stomach discomfort Water additive used to control microbes MRDLG=4 a MRDL=4.0 a
Chlorine dioxide (as CIO2) Anemia; infants and young children: nervous system effects Water additive used to control microbes MRDLG=0.8 a MRDL=0.8 a
Inorganic Chemicals
Aluminum 0.05 to 0.2
Antimony Increase in blood cholesterol; decrease in blood sugar Discharge from petroleum refineries, fire retardants,
ceramics, electronics, solder
0.006 0.006
Arsenic Skin damage or problems with circulatory systems, and may have increased
risk of getting cancer
Erosion of natural deposits; runoff from orchards, runoff
from glass and electronics production wastes
zero 0.010 as of
1/23/06
Asbestos (fiber >10 micrometers) Increased risk of developing benign intestinal polyps Decay of asbestos cement in water mains; erosion of
natural deposits
7 million fibers per liter
(MFL)
7 MFL
Barium Increase in blood pressure Discharge of drilling wastes; discharge from metal
refineries; erosion of natural deposits
2 2
Beryllium Intestinal lesions Discharge from metal refineries and coal-burning
factories; discharge from electrical, aerospace, and
defense industries
0.004 0.004
Cadmium Kidney damage Corrosion of galvanized pipes; erosion of natural
deposits; discharge from metal refineries; runoff from
waste batteries and paints
0.005 0.005
Chloride 250
Water Supply Alternatives Feasibility Report Appendix D
D-2
Final Arlington Feasibility Report.docx
Contaminant Potential Health Effects from Ingestion of Contaminant Sources of Contaminants in Drinking Water
USEPA/Washington DOH
MCLG a
(mg/L) b
MCL or TT a
(mg/L) b
Secondary
Standard
(mg/L)
Chromium (total) Allergic dermatitis Discharge from steel and pulp mills; erosion of natural
deposits
0.1 0.1
Copper Short term exposure: gastrointestinal distress
Long term exposure: liver or kidney damage
People with Wilson’s Disease should consult their personal doctor if the
amount of copper in their water exceeds the action level
Corrosion of household plumbing systems; erosion of
natural deposits
1.3 TT h; Action
Level=1.3
1.0
Cyanide (as free cyanide) Nerve damage or thyroid problems Discharge from steel/metal factories; discharge from
plastic and fertilizer factories
0.2 0.2
Fluoride Bone disease (pain and tenderness of the bones); Children may get mottled
teeth
Water additive which promotes strong teeth; erosion of
natural deposits; discharge from fertilizer and aluminum
factories
4.0 4.0 2.0
Iron 0.3
Lead Infants and children: delays in physical or mental development; children could
show slight deficits in attention span and learning abilities
Adults: kidney problems; high blood pressure
Corrosion of household plumbing systems; erosion of
natural deposits
zero TT g; Action
Level=0.015
Manganese Potential neurotoxicity 0.05
Nickel Heart and liver damage Occurs naturally in soils, ground water and surface
waters and is often used in electroplating, stainless steel
and alloy products
0.1
Mercury (inorganic) Kidney damage Erosion of natural deposits; discharge from refineries and
factories; runoff from landfills and croplands
0.002 0.002
Nitrate (measured as nitrogen) Infants below the age of six months who drink water containing nitrate in
excess of the MCL could become seriously ill and, if untreated, may die.
Symptoms include shortness of breath and blue-baby syndrome.
Runoff from fertilizer use; leaching from septic tanks,
sewage; erosion of natural deposits
10 10
Nitrite (measured as nitrogen) Infants below the age of six months who drink water containing nitrite in
excess of the MCL could become seriously ill and, if untreated, may die.
Symptoms include shortness of breath and blue-baby syndrome.
Runoff from fertilizer use; leaching from septic tanks,
sewage; erosion of natural deposits
1 1
Total nitrate/nitrite (as N) 10
Selenium Hair or fingernail loss; numbness in fingers or toes; circulatory problems Discharge from petroleum refineries; erosion of natural
deposits; discharge from mines
0.05 0.05
Silver 0.10
Sodium Hypertension, cardiac problems 20 20
Sulfate 250
Thallium Hair loss; changes in blood; kidney, intestine, or liver problems Leaching from ore-processing sites; discharge from
electronics, glass, and drug factories
0.0005 0.002
Zinc 5
Organic Chemicals
Acrylamide Nervous system or blood problems; increased risk of cancer Added to water during sewage/wastewater treatment zero TT h
Alachlor Eye, liver, kidney or spleen problems; anemia; increased risk of cancer Runoff from herbicide used on row crops zero 0.002
Atrazine Cardiovascular system or reproductive problems Runoff from herbicide used on row crops 0.003 0.003
Benzene Anemia; decrease in blood platelets; increased risk of cancer Discharge from factories; leaching from gas storage
tanks and landfills
zero 0.005
Benzo(a)pyrene (PAHs) Reproductive difficulties; increased risk of cancer Leaching from linings of water storage tanks and
distribution lines
zero 0.0002
Carbofuran Problems with blood, nervous system, or reproductive system Leaching of soil fumigant used on rice and alfalfa 0.04 0.04
Carbon tetrachloride Liver problems; increased risk of cancer Discharge from chemical plants and other industrial
activities
zero 0.005
Chlordane Liver or nervous system problems; increased risk of cancer Residue of banned termiticide zero 0.002
Water Supply Alternatives Feasibility Report Appendix D
D-3
Final Arlington Feasibility Report.docx
Contaminant Potential Health Effects from Ingestion of Contaminant Sources of Contaminants in Drinking Water
USEPA/Washington DOH
MCLG a
(mg/L) b
MCL or TT a
(mg/L) b
Secondary
Standard
(mg/L)
2,4-D Kidney, liver, or adrenal gland problems Runoff from herbicide used on row crops 0.07 0.07
Dalapon Minor kidney changes Runoff from herbicide used on rights of way 0.2 0.2
1,2-Dibromo-3-chloropropane (DBCP) Reproductive difficulties; increased risk of cancer Runoff/leaching from soil fumigant used on soybeans,
cotton, pineapples, and orchards
zero 0.0002
1,2-Di-chlorobenzene Liver, kidney, or circulatory system problems Discharge from industrial chemical factories 0.6 0.6
1,4-Di-chlorobenzene Anemia; liver, kidney or spleen damage; changes in blood Discharge from industrial chemical factories 0.075 0.075
1,2-Dichloroethane Increased risk of cancer Discharge from industrial chemical factories zero 0.005
1,1-Dichloroethylene Liver problems Discharge from industrial chemical factories 0.007 0.007
cis-1,2-Dichloroethylene Liver problems Discharge from industrial chemical factories 0.07 0.07
trans-1,2-Dichlorothylene Liver problems Discharge from industrial chemical factories 0.1 0.1
Dichloromethane Liver problems; increased risk of cancer Discharge from drug and chemical factories zero 0.005
1,2-Dichloropropane Increased risk of cancer Discharge from industrial chemical factories zero 0.005
Di(2-ethylhexyl) adipate Weight loss, liver problems, or possible reproductive difficulties Discharge from chemical factories 0.4 0.4
Di(2-ethylhexy) phthalate Reproductive difficulties; liver problems; increased risk of cancer Discharge from rubber and chemical factories zero 0.006
Dinoseb Reproductive difficulties Runoff from herbicide used on soybeans and vegetables 0.007 0.007
Dioxin (2,3,7,8-TCDD) Reproductive difficulties; increased risk of cancer Emissions from waste incineration and other combustion;
discharge from chemical factories
zero 0.00000003
Diquat Cataracts Runoff from herbicide use 0.02 0.02
Endothall Stomach and intestinal problems Runoff from herbicide use 0.1 0.1
Endrin Liver problems Residue of banned insecticide 0.002 0.002
Epichlorohydrin Increased cancer risk, and over a long period of time, stomach problems Discharge from industrial chemical factories; an impurity
of some water treatment chemicals
zero TT i
Ethylbenzene Liver or kidney problems Discharge from petroleum refineries 0.7 0.7
Ethylene dibromide Problems with liver, stomach, reproductive system, or kidneys; increased risk
of cancer
Discharge from petroleum refineries zero 0.00005
Glyphosate Kidney problems; reproductive difficulties Runoff from herbicide use 0.7 0.7
Heptachlor Liver damage; increased risk of cancer Residue of banned termiticide zero 0.0004
Heptachlor epoxide Liver damage; increased risk of cancer Breakdown of heptachlor zero 0.0002
Hexachlorobenzene Liver or kidney problems; reproductive difficulties; increased risk of cancer Discharge from metal refineries and agricultural chemical
factories
zero 0.001
Hexachlorocyclopentadiene Kidney or stomach problems Discharge from chemical factories 0.05 0.05
Lindane Liver or kidney problems Runoff/leaching from insecticide used on cattle, lumber,
gardens
0.0002 0.0002
Methoxychlor Reproductive difficulties Runoff/leaching from insecticide used on fruits,
vegetables, alfalfa, livestock
0.04 0.04
Oxamyl (Vydate) Slight nervous system effects Runoff/leaching from insecticide used on apples,
potatoes, and tomatoes
0.2 0.2
Polychlorinated biphenyls (PCBs) Skin changes; thymus gland problems; immune deficiencies; reproductive or
nervous system difficulties; increased risk of cancer
Runoff from landfills; discharge of waste chemicals zero 0.0005
Pentachlorophenol Liver or kidney problems; increased cancer risk Discharge from wood preserving factories zero 0.001
Picloram Liver problems Herbicide runoff 0.5 0.5
Simazine Problems with blood Herbicide runoff 0.004 0.004
Styrene Liver, kidney, or circulatory system problems Discharge from rubber and plastic factories; leaching
from landfills
0.1 0.1
Tetrachloroethylene Liver problems; increased risk of cancer Discharge from factories and dry cleaners zero 0.005
Water Supply Alternatives Feasibility Report Appendix D
D-4
Final Arlington Feasibility Report.docx
Contaminant Potential Health Effects from Ingestion of Contaminant Sources of Contaminants in Drinking Water
USEPA/Washington DOH
MCLG a
(mg/L) b
MCL or TT a
(mg/L) b
Secondary
Standard
(mg/L)
Toluene Nervous system, kidney, or liver problems Discharge from petroleum factories 1 1
Toxaphene Kidney, liver, or thyroid problems; increased risk of cancer Runoff/leaching from insecticide used on cotton and
cattle
zero 0.003
2,4,5-TP (Silvex) Liver problems Residue of banned herbicide 0.05 0.05
1,2,4-Trichlorobenzene Changes in adrenal glands Discharge from textile finishing factories 0.07 0.07
1,1,1-Trichloroethane Liver, nervous system, or circulatory problems Discharge from metal degreasing sites and other
factories
0.20 0.20
1,1,2-Trichloroethane Liver, kidney, or immune system problems Discharge from industrial chemical factories 0.003 0.005
Trichloroethylene Liver problems; increased risk of cancer Discharge from metal degreasing sites and other
factories
zero 0.005
Vinyl chloride Increased risk of cancer Leaching from PVC pipes; discharge from plastic factories zero 0.002
Xylenes (total) Nervous system damage Discharge from petroleum factories; discharge from
chemical factories
10 10
Radionuclides
Alpha particles Increased risk of cancer Erosion of natural deposits of certain minerals that are
radioactive and may emit a form of radiation known as
alpha radiation
zero 15 picocuries per
Liter (pCi/L)
Beta particles and photon emitters Increased risk of cancer Decay of natural and man-made deposits of certain
minerals that are radioactive and may emit forms of
radiation known as photons and beta radiation
zero
4 millirems per year
Radium 226 and Radium 228 (combined) Increased risk of cancer Erosion of natural deposits
zero
5 pCi/L
Uranium Increased risk of cancer, kidney toxicity Erosion of natural deposits zero 30 ug/L as of
12/08/03
Secondary Standard
Color 15
(color units)
Corrosivity noncorrosive
Foaming agents 0.5 mg/L
Odor 3 threshold odor
number
pH 6.5-8.5
Specific conductance 700 µmhos/cm
Total dissolved solids 500 mg/L
See Notes on following page.
Water Supply Alternatives Feasibility Report Appendix D
D-5
Final Arlington Feasibility Report.docx
Notes
a. Definitions:
Maximum contaminant level (MCL): The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs as feasible using the best available treatment technology and taking cost into consideration. MCLs are enforceable
standards.
Maximum contaminant level goal (MCLG): The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety and are non-enforceable public health goals.
Maximum residual disinfectant level (MRDL): The highest level of a disinfectant allowed in drinking water. There is convincing evidence that addition of a disinfectant is necessary for control of microbial contaminants.
Maximum residual disinfectant level goal (MRDLG): The level of a drinking water disinfectant below which there is no known or expected risk to health. MRDLGs do not reflect the benefits of the use of disinfectants to control microbial contaminants.
Treatment technique: A required process intended to reduce the level of a contaminant in drinking water.
b. Units are in milligrams per liter (mg/L) unless otherwise noted. Milligrams per liter are equivalent to parts per million.
c. USEPA’s surface water treatment rules require systems using surface water or ground water under the direct influence of surface water (GWUDI) to (1) disinfect their water, and (2) filter their water or meet criteria for avoiding filtration so that the following
contaminants are controlled at the following levels:
Cryptosporidium: (as of 1/1/02 for systems serving >10,000 and 1/14/05 for systems serving <10,000) 99% removal.
Giardia lamblia: 99.9% removal/inactivation
Viruses: 99.99% removal/inactivation
Legionella: No limit, but EPA believes that if Giardia and viruses are removed/inactivated, Legionella will also be controlled.
Turbidity: At no time can turbidity (cloudiness of water) go above 5 nephelometric turbidity units (NTU); systems that filter must ensure that turbidity not exceed 1 NTU (0.5 NTU for conventional or direct filtration) in at least 95% of the daily samples
in any month. As of January 1, 2002, turbidity may never exceed 1 NTU, and must not exceed 0.3 NTU in 95% of daily samples in any month.
HPC: No more than 500 bacterial colonies per milliliter.
Long Term 1 Enhanced Surface Water Treatment (Effective Date: January 14, 2005); Surface water systems or (GWUDI) systems serving fewer than 10,000 people must comply with the applicable Long Term 1 Enhanced Surface Water Treatment
Rule provisions (e.g., turbidity standards, individual filter monitoring, cryptosporidium removal requirements, updated watershed control requirements for unfiltered systems).
Filter Backwash Recycling: The Filter Backwash Recycling Rule requires systems that recycle to return specific recycle flows through all processes of the system’s existing conventional or direct filtration system or at an alternative location approved
by the state.
d. Fecal coliform and E. coli are bacteria whose presence indicates that the water may be contaminated with human or animal wastes. Disease-causing microbes (pathogens) in these wastes can cause diarrhea, cramps, nausea, headaches, or other
symptoms. These pathogens may pose a special health risk for infants, young children, and people with severely compromised immune systems.
e. No more than 5.0% of samples can be total coliform-positive in a month. (For water systems that collect fewer than 40 routine samples per month, no more than one sample can be total coliform-positive per month.) Every sample that has total coliform
must be analyzed for either fecal coliform or E. coli. If there are two consecutive TC-positive samples, and one is also positive for E. coli or fecal coliform, of if there are two consecutive samples either positive for E. coli or fecal coliform, the system has an
acute MCL violation.
f. Although there is no collective MCLG for this contaminant group, there are individual MCLGs for some of the individual contaminants:
Trihalomethanes: bromodichloromethane (zero); bromoform (zero); dibromochloromethane (0.06 mg/L). Chloroform is regulated with this group but has no MCLG.
Haloacetic acids: dichloroacetic acid (zero); trichloroacetic acid (0.3 mg/L). Monochloroacetic acid, bromoacetic acid, and dibromoacetic acid are regulated with this group but have no MCLGs.
g. MCLGs were not established before the 1986 Amendments to the Safe Drinking Water Act. Therefore, there is no MCLG for this contaminant.
h. Lead and copper are regulated by a Treatment Technique that requires systems to control the corrosiveness of their water. If more than 10% of tap water samples exceed the action level, water systems must take additional steps. For copper, the action
level is 1.3 mg/L, and for lead 0.015 mg/L.
i. Each water system must certify, in writing, to the state (using third-party or manufacturer’s certification) that when acrylamide and epichlorohydrin are used in drinking water systems, the combination (or product) of dose and monomer level does not
exceed the levels specified, as follows:
Acrylamide = 0.05% dosed at 1 mg/L (or equivalent)
Epichlorohydrin = 0.01% dosed at 20 mg/L (or equivalent)
Appendix E: Workshop 1 Meeting Notes
City of Arlington
BCE Workshop 1 Notes
On September 2, 2010 a business case evaluation (BCE) workshop was conducted with the City of
Arlington to discuss their water rights and possible water treatment alternatives for increasing
treatment capacity to perfect the water rights.
The agenda for the meeting is listed below followed by the meeting attendees.
AGENDA ITEM TIME
I. Introduction 5 Minutes
II. BCE Process Overview 15 Minutes
III. Discuss Problem Statement and Project Expectation (Level of
Service) 25 Minutes
IV. Identify Alternatives 60 Minutes
V. Break 15 Minutes
VI. Review Goals and Discuss Risk/Benefits of Alternatives 30 Minutes
VII. Screen Alternatives 45 Minutes
VIII. Lunch 30 Minutes
IX. Discuss Additional Information Needs, if required 60 Minutes
X. Wrap Up 15 Minutes
Meeting attendees:
City of Arlington
Don Smith
Dallas Speed
Bill Cochinella
Mike Wolanek
Jim Kelly
Brown and Caldwell
Bill Persich
Matt Maring
Lynn Williams
Steffran Neff
City of Arlington
BCE Workshop 1 Notes
Meeting Notes
Problem Definition
Water supply needs to be incrementally expanded in an economical manner to keep pace
with projected future water demands
Water rights need to be developed consistent with justifiable near/long term water demand
projections and without placing established water rights in jeopardy
Develop future water rights in a manner that is both cost effective and considers
environmental restraints
Levels of Service
Water rights planning consistent with justifiable water demand projections
Sustainable annual water supply capacity > ADD
Peak water supply capacity > MDD
PHD above MDD supplied through equalizing storage
Distribution system leakage < 10 percent of total annual water production
Water quality consistent with existing and anticipated future regulations
WUE measures and goals fulfilled
Water system that allows low impact on the river and minimizes operational complexities
Priority for the PSPL right as it is seen to be free
Ability to have capacity to use full PSPL water right
Build sustainability and flexibility into water system
Water quality and supply redundancy - don't have a protected basin and are growing
Fix airport well and fully utilize existing water rights before other suppliers are considered
General Information
The desire is to get PSPL right revalidated
They have a 1992 Airport application for 900 gpm but have not pursued it yet in order to
prioritize the PSPL right at Haller
Have 2700 gpm of water rights to rely on today
Currently the treatment system cannot produce enough water for which Arlington has the
rights to use
Have an issue with the Haller well, cannot get 1700. Only getting 1600 at best - Well used
to drop only 6 feet now it is covered 10 or more
With 2 percent growth the City will not have enough water in 2016
There is a possiblity to put water rights in temporary trust for 20 years if needed
Want to maintain a safety/reliability cushion of capacity
Need to get the department of health data and others to figure out the safety/reliability
cushion
Would need to move well site north to utilize the extra 900 gpm
Will be easier to move rights to Haller
7000 would be a good number for the long-term potential rights
Population growth is assumed to be 30000 by 2027 and then 2% growth from 2030 onward
Arlington would like for BC to show a table with the water right, the maximum day demand,
and production capacity for each alternative and to look at instantaneous as well as annual
BC is to assume water right is equivalent to the production
May consider providing storage for maximum instantaneous demand plus fire flow
City of Arlington
BCE Workshop 1 Notes
There is a concern with aquifer storage recharge (ASR) with soil and geology
In emergency situation, could use the PUD water supply
Current price for salt is $4.6 per bag for 40 pounds use 1 bag per day
BC should treat labor as a fixed cost only include variable such as power and chemicals for
O&M
Alternatives - Risks, Benefit, and O&M Considerations
Haller Wellfield and WTP
Gravity media filter expansion consistent w/ surface water rights
o Familiarity with process
o Lowest cost
Membrane filter expansion consistent w/ surface water rights plus existing gravity media
filters
o Risk
Energy use high
R&R cost high
o Benefit
Positive barrier
footprint
ability to modulize
Membrane filter expansion and gravity media filter replacement consistent w/ surface water
rights
o Need to run two types of plants
o Consider bringing dedicated sources to certain treatment
o More complex controls for hybrid
Actiflo
o Risk
Cost
More machinery
o Benefit
Good for variable turbidity
Small footprint
Would handle unexpected event
Alternative conventional treatment
Fatally flawed because Arlington does not have high enough turbidity
Restore the rated capacity
Consider the capacity of both the plant and the well field
Risks
o Highly vulnerable
o Variable WQ differences in existing wells
o Difficulty in constructing and locating new wells
o Unknown water quality in new wells
o Chemical doses at plant is not set up for different water sources
o Not designed for large fluctuations for anything
o Taste and Odor - one treatment instance in recorded complaints
o Mn in the water
City of Arlington
BCE Workshop 1 Notes
o History of disturbance impacts
o Climate - May be mitigated due to GW intake
o Need new PLC and controls
o New wells might affect water quality
Benefits
o Excellent water quality with low turbidity
o Low treatment costs
o Proximity to source
o Ability to show the water right
O&M concerns
o Up to 2500 gpm, the clearwell will be OK
o Convert to a conventional treatment
o Blend water quality with number 1, normally do not use alone
o Well 1 in 2001, only 36' deep when they aimed for 45' due to geology
o Consider design with modulization for potential future upgrades
o Consider green sand
o No increase in staff
Airport well replacement and treatment consistent w/ existing water rights limits
Risks
o Increased Mn in water
o Unconfined aquifer in an industrial area
o Environmental/tribal appeals and permitting process
o Mitigation may be necessary
Benefits
o Diversify water sources
o O&M concerns
o More complex O&M with running two systems
o O&M restricted access depending on site
o No increase in labor cost
Other
o There was an airport 2 well tested
o Upgrade to 580
o Upgrade to full to 1480 gpm from 1992 application
o Transfer WR to go to 1700 gpm
o Need to drill multiple wells and might be north of existing well
o Land use and potential industrialization issues
Going somewhere other than airport or Haller to drill well such as Burn Hill
The City stated to list as a concept, but not to cost for this effort
SnoCoPUD supply expansion
Risks
o Have 2018 sunset on current contract
o Cost per water changes yearly
o Limited water right
o Everett supply is limited have a 1950s application
o Out of basin water
o Lack of control over water quality
o Capital contribution of $13M
Benefits
City of Arlington
BCE Workshop 1 Notes
o All gravity - no added pumping
o Finished fluoridated water
o Augment river
O&M concerns
o Need to implement better controls for flow control through reservoir management
o All manual needs automation
Marysville intertie supply
Risks
o Marysville would take priority and could pull water back
o Marysville does not want to treat Arlington as a customer
Benefits
o Marysville has 5 cfs continuous
O&M concerns
o Downstream of Arlington wastewater outfall
o Requires pumping
o Still have a connection but would have to isolate the Arlington system to use
o Different pressure zone
o In the 240ish zone
o Would just want to use for emergency purposes
Increased water conservation
Risks
o less revenue
o lack of direct control over capacity gain
Benefits
o delay capital expenditure
o O&M concerns
o 87 gallons per capita is a low use
o 2 percent by 2014; 5 percent by 2028
Decrease potable water demands via increased reclaimed water supply
Could potentially use reclaimed water in exchange for irrigation or golf course right
Develop wholesale/regional water supply capability
The city said not to cost at this point, but keep on list as future consideration
ASR/bulk storage reservoir
There was a discussion that the geology would not be good for ASR, but it was not an
exhausted study
Could look at Burn Hill as a recharge site
Need to study further
Tattoosh Aquifer
Risks
o Too far
o Costly
Tulalip purchase
Risks
City of Arlington
BCE Workshop 1 Notes
o Negotiations for water right would be uncertain
o Getting water from casino to Arlington would be a capital cost
The City said not to review for this assessment
Alternatives to keep for BCE Workshop 2 cost analysis
1. Do nothing - 1500 gpm (Haller WTP)+ 200 gpm (Airport well)+1000 gpm (PUD connection)
2. Restore and Upgrade Haller Wellfield and WTP to maximum 1,835 gpm peak capacity
3. Restore Airport well to original 580 gpm peak capacity without treatment for iron and
manganese
4. Restore Airport well to original 580 gpm peak capacity with treatment for iron and
manganese
5. Increase Haller Wellfield and WTP peak capacity to 2,500 gpm with packaged sand filtration
6. Increase Haller Wellfield and WTP peak capacity to 4,369 gpm with packaged sand filtration
7. Increase the peak capacity at the Airport well to 1,480 gpm with treatment for iron and
manganese
8. Increase the peak capacity at the Airport well to 1,700 gpm with treatment for iron and
manganese
9. Increase peak PUD purchase to 3,000 gpm
Appendix F: 2009 Water Production Cost Estimate
WATER TREATMENT PLANT 2009 EXPENSES
EXPENDITURE LINE ITEM JAN FEB MAR APR MAY JUN JULY AUG SEPT OCT NOV DEC TOTALS
Operating Supplies $6,165 $1,594 $2,210 $5,395 $1,456 $4,365 $5,560 $1,564 $9,316 $1,821 $39,445.10
Operating Permit $5,625 $5,625.40
Regulatory Compliance & Equip.$287 $304 $2,282 $2,243 $387 $2,703 $1,388 $669 $747 $342 $11,351.64
Insurance $4,868 $4,868.09
Public Utility Service $3,595 $4,671 $3,276 $3,213 $3,125 $4,340 $4,488 $4,649 $4,141 $3,970 $39,466.17
Repairs & Maintenance $172 $3,507 $522 $470 $230 $4,179 $9,079.93
Telephone System $155 $155 $155 $155 $155 $155 $155 $155 $155 $155 $1,550.00
Salaries & Benefits $21,984 $22,308 $21,345 $21,455 $19,949 $21,302 $20,548 $20,835 $20,195 $20,494 $20,638 $231,054.15
PWTF Loan Payments $98,068 $98,068.00
$440,508.48
Annual Cost Estimate $480,554.71
2009 production (gals) 318,535,769
Unit cost ($/gal) $0.0015
2009 production (ccf) 425,850
Unit cost ($/ccf) $1.13
Water
produced at
Haller and
Airport well
fields in
2009
City of Arlington
Council Agenda Bill
AGENDA ITEM:
ATTACHMENT E
COUNCIL WORKSHOP DATE:
July 11, 2011
SUBJECT: Dedication Plaque for the
Wastewater Treatment Plant Upgrade and
Expansion Project
DEPARTMENT OF ORIGIN:
Public Works – Utilities Division
James Kelly
ATTACHMENTS:
• Preliminary proof attached, proof to be handed out at Council Workshop
EXPENDITURES REQUESTED: N/A
BUDGET CATEGORY: N/A
LEGAL REVIEW: Pending review by City Atty
DESCRIPTION: Proposed dedication plaque for the Wastewater Treatment Plant Upgrade and
Expansion Project.
HISTORY: It is customary to provide a dedication plaque honoring the public leaders,
consultants, and contractors who guided and supported the design and construction of a major
public improvement project.
The Wastewater Treatment Plant Upgrade and Expansion Project is the largest public
improvement project undertaken by Arlington. As such, a dedication plaque will cite the
service provided by the Mayor, the City Council, the Public Works Director, the Engineering
firm, the Contractor, and funding sources.
ALTERNATIVES:
- No Action at this time
RECOMMENDED ACTION:
- No Action at this time
City of Arlington
Council Agenda Bill
AGENDA ITEM:
ATTACHMENT F
COUNCIL MEETING DATE:
July 11, 2011
SUBJECT:
FEMA Floodplain Regulations
DEPARTMENT OF ORIGIN:
Community Development – Bill Blake
ATTACHMENTS:
1. Draft regulations
EXPENDITURES REQUESTED: -0-
BUDGET CATEGORY: N/A
LEGAL REVIEW:
Has not yet been reviewed
DESCRIPTION: This document is a draft set up regulations that has been developed to meet
federally required improvements to the National Flood Insurance program (NFIP) managed by
FEMA.
HISTORY: The National Marine Fisheries Service issued a Biological Opinion in 2008 that the
current NFIP was causing the take of ESA listed species including Chinook Salmon and Orca
whales. FEMA working with State, Federal and Local agencies developed an acceptable level of
improvements a local government could take to improve their floodplain ordinances. Three
choices include 1. Adopting the federally developed “model ordinance 2. Updating your
existing ordinance to meet the requirements 3. Having each floodplain project go through the
federal ESA review process. This draft ordinance was developed by enhancing the existing
Arlington floodplain ordinance (We were fairly close already). If Council authorizes staff, the
draft would be sent to FEMA for their review. We would have legal review prior to sending to
Council for adoption. Adoption is required on September 22, 2011, which includes a one year
extension as it was actually due last September. If not adopted by Sept 22, the default is each
project goes through federal review.
ALTERNATIVES:
No action.
RECOMMENDED MOTION:
No action.
Title 20—Land Use Code Chapter 20.64: Flooding, Drainage, & Erosion
City of Arlington 20.64 - 1 November 2010
Chapter 20.64
FLOODWAYS, FLOODPLAINS, DRAINAGE, AND EROSION
Sections:
Part I. Floodways and Floodplains
20.64.010 Statutory Authorization.
20.64.020 Findings of Fact.
20.64.030 Statement of Purpose.
20.64.040 Methods of Reducing Flood Losses.
20.64.050 Definitions
20.64.060 Basis for Establishing the Areas of Special Flood Hazard
20.64.070 Abrogation and Greater Restrictions
20.64.080 Interpretation
20.64.090 Warning and Disclaimer of Liability
20.64.100 Supplementary Information Required with a Permit Application.
20.64.110 Conformance with Chapter 20.88 (Environmentally Critical Areas
20.64.120 Location of Boundaries of Floodplain, Riparian Habitat Zone
20.64.130 Setbacks from Streams Outside Designated Floodplains.
20.64.140 Artificial Obstructions Within Floodways Prohibited.
20.64.150 Permissible Uses Within Floodways.
20.64.160 Construction Within Floodways and Floodplains Restricted, Habitat Protection.
20.64.180 Specific Standards for Zones A1-30, AH, and AE
20.64.190 Specific Standards for Designated Regulatory Floodways.
20.64.200 Specific Standards For Shallow Flooding Areas (AO Zones)
20.64.210 Encroachments
20.64.220 Special Provisions for Subdivisions.
20.64.230 Utility Systems in Floodways and Floodplains.
20.64.240 Critical Facility.
20.64.250 Additional Duties of Administrator Related to Flood Insurance and Flood Control.
20.64.260 Variances from Requirements.
Part II. Drainage, Erosion Control, Storm Water Management
20.64.300 Stormwater Management.
Part I. Floodways and Floodplains
20.64.010 Statutory Authorization.
The Legislature of the State of Washington has delegated the responsibility to local
governmental units to adopt regulations designed to promote the public health, safety, and
general welfare of its citizenry. Therefore, the City of Arlington does ordain as follows:
20.64.020 Findings of Fact.
(a) The flood hazard areas of Arlington are subject to periodic inundation which results in loss of
life and property, health, and safety hazards, disruption of commerce and governmental
services, extraordinary public expenditures for flood protection and relief, and impairment of
the tax base, all of which adversely affect the public health, safety, and general welfare.
(b) These flood losses are caused by the cumulative effect of obstructions in areas of special
flood hazards that increase flood heights and velocities, and when inadequately anchored,
Title 20—Land Use Code Chapter 20.64: Flooding, Drainage, & Erosion
City of Arlington 20.64 - 2 November 2010
damage uses in other areas. Uses that are inadequately floodproofed, elevated, or
otherwise protected from flood damage also contribute to the flood loss.
20.64.030 Statement of Purpose.
(a) It is the purpose of this ordinance to promote the public health, safety, and general welfare,
and to minimize public and private losses due to flood conditions in specific areas by
provisions designed:
(b) To protect human life and health;
(b)(c) To manage development in a manner reducing impacts to floodplain processes;
(c)(d) To minimize expenditure of public money and costly flood control projects;
(d)(e) To minimize the need for rescue and relief efforts associated with flooding and generally
undertaken at the expense of the general public;
(e)(f) To minimize prolonged business interruptions;
(f)(g) To minimize damage to public facilities and utilities such as water and gas mains,
electric, telephone and sewer lines, streets, and bridges located in areas of special flood
hazard;
(g)(h) To help maintain a stable tax base by providing for the sound use and development of
areas of special flood hazard so as to minimize future flood blight areas;
(h)(i) To ensure that potential buyers are notified that property is in an area of special flood
hazard; and,
(i)(j) To ensure that those who occupy the areas of special flood hazard assume
responsibility for their actions.
20.64.040 Methods of Reducing Flood Losses.
In order to accomplish its purposes, this ordinance includes methods and provisions for:
(a) Restricting or prohibiting uses which are dangerous to health, safety, and property due to
water or erosion hazards, or which result in damaging increases in erosion or in flood
heights or velocities;
(b) Requiring that uses vulnerable to floods, including facilities which serve such uses, be
protected against flood damage at the time of initial construction;
(c) Controlling the alteration of natural flood plains, stream channels, wetlands and natural
protective barriers, which help accommodate or channel flood waters;
(d) Controlling filling, grading, dredging, and other development which may increase flood
damage; and
(e) Preventing or regulating the construction of flood barriers that will unnaturally divert
floodwaters or may increase flood hazards in other areas.
20.64.050 Definitions.
Unless specifically defined below, words or phrases used in this ordinance shall be interpreted
so as to give them the meaning they have in common usage and to give this ordinance its most
reasonable application.
“Appeal” means a request for a review of the interpretation of any provision of this ordinance
or a request for a variance.
“Area of Shallow Flooding” means a designated AO, or AH Zone on the Flood Insurance
Rate Map (FIRM). The base flood depths range from one to three feet; a clearly defined channel
does not exist; the path of flooding is unpredictable and indeterminate; and, velocity flow may be
evident. AO is characterized as sheet flow and AH indicates ponding.
“Area of Special Flood Hazard” means the land in the floodplain within a community subject
to a one-percent or greater chance of flooding in any given year. Designation on maps always
includes the letters A or V.
Title 20—Land Use Code Chapter 20.64: Flooding, Drainage, & Erosion
City of Arlington 20.64 - 3 November 2010
“Base Flood” means the flood having a 1% chance of being equaled or exceeded in any
given year (also referred to as the “100-year flood”). Designated on Flood Insurance Rate Maps
by the letters A or V.
“Basement” means any area of the building having its floor subgrade (below ground level)
on all sides.
“Channel Migration Zone” means the lateral extent of likely movement along a stream reach
during the next one hundered years with evidence of active stream channel movement over the
past one hundered years.
“Critical Facility” means a facility for which even a slight chance of flooding might be too
great. Critical facilities include, but are not limited to schools, nursing homes, hospitals, police,
fire and emergency response installations, installations that produce, use or store hazardous
materials or hazardous waste.
“Development” means any man-made change to improved or unimproved real estate,
including but not limited to buildings or other structures, mining, dredging, filling, grading,
paving, excavation or drilling operations or storage of equipment or materials located within the
area of special flood hazard, subdivision of land, removal of substantial amounts of vegetation,
or alteration of natural site characteristics.
“Elevated Building” means for insurance purposes, a non-basement building that has its
lowest elevated floor raised above ground level by foundation walls, shear walls, post, piers,
pilings, or columns.
“Existing Manufactured Home Park Or Subdivision” means a manufactured home park or
subdivision for which the construction of facilities for servicing the lots on which the
manufactured homes are to be affixed (including, at a minimum, the installation of utilities, the
construction of streets, and either final site grading or the pouring of concrete pads) is
completed before the effective date of the adopted floodplain management regulations.
“Expansion To An Existing Manufactured Home Park Or Subdivision” means the preparation
of additional sites by the construction of facilities for servicing the lots on which the
manufactured homes are to be affixed (including the installation of utilities, the construction of
streets, and either final site grading or the pouring of concrete pads).
“Flood” or “Flooding” means a general and temporary condition of partial or complete
inundation of normally dry land areas from:
(a) The overflow of inland or tidal waters and/or
(b) The unusual and rapid accumulation of runoff of surface waters from any source.
“Flood Insurance Rate Map (Firm)” means the official map on which the Federal Insurance
Administration has delineated both the areas of special flood hazards and the risk premium
zones applicable to the community.
“Flood Insurance Study” means the official report provided by the Federal Insurance
Administration that includes flood profiles, the Flood Boundary-Floodway Map, and the water
surface elevation of the base flood.
“Floodplain Administrator.” The Director of Development ServicesCommunity Development
is hereby deemed to be the City’s Floodplain Administrator. (Added by Ord. No. 1351, 9/7/04)
“Floodway” means the channel of a river or other watercourse and the adjacent land areas
that must be reserved in order to discharge the base flood without cumulatively increasing the
water surface elevation more than one foot.
“Lowest Floor” means the lowest floor of the lowest enclosed area (including basement). An
unfinished or flood resistant enclosure, usable solely for parking of vehicles, building access or
storage, in an area other than a basement area, is not considered a building’s lowest floor,
provided that such enclosure is not built so as to render the structure in violation of the
applicable non-elevation design requirements found in §20.64.180(a)2 (Specific Standards for
Zones A1-30, AH, and AE).
Title 20—Land Use Code Chapter 20.64: Flooding, Drainage, & Erosion
City of Arlington 20.64 - 4 November 2010
“Manufactured Home” means a structure, transportable in one or more sections, which is
built on a permanent chassis and is designed for use with or without a permanent foundation
when attached to the required utilities. The term “manufactured home” does not include a
“recreational vehicle.”
“Manufactured Home Park Or Subdivision” means a parcel (or contiguous parcels) of land
divided into two or more manufactured home lots for rent or sale.
“New Construction” means structures for which the “start of construction” commenced on or
after the effective date of this ordinance.
“New Manufactured Home Park Or Subdivision” means a manufactured home park or
subdivision for which the construction of facilities for servicing the lots on which the
manufactured homes are to be affixed (including at a minimum, the installation of utilities, the
construction of streets, and either final site grading or the pouring of concrete pads) is
completed on or after the effective date of adopted floodplain management regulations.
“Recreational Vehicle” means a vehicle that is:
(a) Built on a single chassis;
(b) 400 square feet or less when measured at the largest horizontal projection;
(c) Designed to be self-propelled or permanently towable by a light duty truck; and
(d) Designed primarily not for use as a permanent dwelling but as temporary living quarters for
recreational, camping, travel, or seasonal use.
(d) (e) “Riparian Habitat Zone” an area identified on the approved map that provides the
necessary protection perpendicularly from, 1. The ordinary high water mark 2. The Channel
Migration Zone, 3. The mapped Floodway.
“Start Of Construction” includes substantial improvement, and means the date the building
permit was issued, provided the actual start of construction, repair, reconstruction, placement or
other improvement was within 180 days of the permit date. The actual start means either the
first placement of permanent construction of a structure on a site, such as the pouring of slab or
footings, the installation of piles, the construction of columns, or any work beyond the stage of
excavation; or the placement of a manufactured home on a foundation. Permanent construction
does not include land preparation, such as clearing, grading and filling; nor does it include the
installation of streets and/or walkways; nor does it include excavation for a basement, footings,
piers, or foundations or the erection of temporary forms; nor does it include the installation on
the property of accessory buildings, such as garages or sheds not occupied as dwelling units or
not part of the main structure. For a substantial improvement, the actual start of construction
means the first alteration of any wall, ceiling, floor, or other structural part of a building, whether
or not that alteration affects the external dimensions of the building.
“Structure” means a walled and roofed building including a gas or liquid storage tank that is
principally above ground.
“Substantial Damage” means damage of any origin sustained by a structure whereby the
cost of restoring the structure to its before damaged condition would equal or exceed 50 percent
of the market value of the structure before the damage occurred.
“Substantial Improvement” means any repair, reconstruction, or improvement of a structure,
the cost of which equals or exceeds 50 percent of the market value of the structure either:
(a) Before the improvement or repair is started; or
(b) If the structure has been damaged and is being restored, before the damage occurred. For
the purposes of this definition “substantial improvement” is considered to occur when the
first alteration of any wall, ceiling, floor, or other structural part of the building commences,
whether or not that alteration affects the external dimensions of the structure.
The term does not, however, include either:
(c) Any project for improvement of a structure to correct existing violations of state or local
health, sanitary, or safety code specifications which have been identified by the local code
Title 20—Land Use Code Chapter 20.64: Flooding, Drainage, & Erosion
City of Arlington 20.64 - 5 November 2010
enforcement official and which are the minimum necessary to assure safe living conditions,
or
(d) Any alteration of a “historic structure,” provided that the alteration would not preclude the
structure’s continued designation as a “historic structure.”
“Variance” means a grant of relief from the requirements of this ordinance that permits
construction in a manner that would otherwise be prohibited by this ordinance.
“Water Dependent” means a structure for commerce or industry that cannot exist in any
other location and is dependent on the water because of the intrinsic nature of its operations.
20.64.060 Basis for Establishing the Areas of Special Flood Hazard.
(a) The areas of special flood hazard identified by the Federal Insurance Administration in a
scientific and engineering report entitled “The Flood Insurance Study for Snohomish County”
(in which the City of Arlington is incorporated) dated November 8, 1999September 29, 2006,
or as amended, with an accompanying Flood Insurance Rate Map (FIRM), as amended, are
hereby adopted by reference and declared to be a part of this ordinance. The Flood
Insurance Study and the FIRM are on file at Arlington City Hall, 238 North Olympic,
Arlington, Washington. The best available information for flood hazard area identification as
outlined in Subsection (b) shall be the basis for regulation until a new FIRM is issued which
incorporates the data utilized under Subsection (b).
(b) When base flood elevation data has not been provided (A and V Zones) in accordance with
Subsection (a), the administrator shall use any base flood elevation and floodway data
available from a Federal, State or other source, in order to comply with §20.64.180 (Specific
Standards for Zones A1-30, AH, and AE) and §20.64.190 (Specific Standards for
Designated Regulatory Floodways). (Amended by Ord. 1365, 6/13/05)
(c) If such data are not already available, the administrator may rely on a licensed surveyor to
provide such information as necessary to reasonably ascertain said zones.
20.64.070 Abrogation and Greater Restrictions
This ordinance is not intended to repeal, abrogate, or impair any existing easements,
covenants, or deed restrictions. However, where this ordinance and another ordinance,
easement, covenant, or deed restriction conflict or overlap, whichever imposes the more
stringent restrictions shall prevail.
20.64.080 Interpretation
In the interpretation and application of this ordinance, all provisions shall be:
(a) Considered as minimum requirements;
(b) Liberally construed in favor of the governing body; and,
(c) Deemed neither to limit nor repeal any other powers granted under State statutes.
20.64.090 Warning and Disclaimer of Liability
The degree of flood protection required by this ordinance is considered reasonable for
regulatory purposes and is based on scientific and engineering considerations. Larger floods
can and will occur on rare occasions. Flood heights may be increased by man-made or natural
causes. This ordinance does not imply that land outside the areas of special flood hazards or
uses permitted within such areas will be free from flooding or flood damages. This ordinance
shall not create liability on the part of City of Arlington, any officer or employee thereof, or the
Federal Insurance Administration, for any flood damages that result from reliance on this
ordinance or any administrative decision lawfully made hereunder.
Title 20—Land Use Code Chapter 20.64: Flooding, Drainage, & Erosion
City of Arlington 20.64 - 6 November 2010
20.64.100 Supplementary Information Required with a Permit Application.
In addition to the standard information required with a permit application (§20.16.040,
Applications To Be Complete), the following information is also required for any permits
proposing development within a floodway or floodplain:
(a) Elevation in relation to mean sea level, of the lowest floor (including basement) of all
structures;
(b) Elevation in relation to mean sea level to which any structure has been flood-proofed;
(c) Certification by a registered professional engineer or architect that the flood-proofing
methods for any nonresidential structure meet the flood-proofing criteria in Subsection
20.64.180(b) (Specific Standards for Zones A1-30, AH, and AE); and
(d) Description of the extent to which a watercourse will be altered or relocated as a result of
proposed development.
20.64.110 Conformance with Chapter 20.88 (Environmentally Critical Areas).
Wherever this section allows uses within a floodway or floodplain, that use must also be
consistent with Chapter 20.88 (Environmentally Critical Areas) and Chapter 20.92 (Shoreline
Management) in terms of both allowable use and location of use. In any case, wherever
regulations in these two Chapters conflict, the more restrictive shall prevail. The explicit intent of
this section is to not allow development that is inconsistent with Chapter 20.88 or Chapter 20.92
to occur in the restricted areas or buffers required by that Chapter, even though it may seem
permissible according to the regulations of this chapter.
20.64.120 Location of Boundaries of Floodplain and, Floodway Districts and Riparian Habitat
Zone..
(a). As used in this chapter, the terms floodplain and floodway refer in the first instance to
certain areas whose boundaries are determined and can be located on the ground by reference
to the specific fluvial characteristics set forth in the definitions of these terms. These terms also
refer to overlay zoning districts whose boundaries correspond to the actual physical location of
floodways and floodplains as shown on FEMA’s Flood Insurance Rate Map (FIRM) and should
be shown on the map identified in §20.36.10092 (Official Zoning MapShoreline Master Plan).
(These overlay districts thus differ from other zoning districts whose boundaries are established
solely according to planning or policy, rather than physical, criteria.) Therefore, the administrator
is authorized to make necessary interpretations as to the exact location of the boundaries of
floodways or floodplains if there appears to be a conflict between a mapped boundary and
actual field conditions. Such interpretations, like other decisions of the administrator, may be
appealed pursuant to §20.20.010 (Appeals).
(b). As used in this chapter the term Riparian Habitat Zone (RHZ) is identified on the approved
RHZ map. The RHZ is an overlay zone that encompasses lands as defined above on either
side of all stream, and for all other watercourse including off channel areas within the Special
Flood Hazard Areas. The RHZ is a no new disturbance zone, other than for activities that will
not adversely affect the existing habitat function. Any property or portion thereof that lies within
the RHZ is subject to the restrictions of the RHZ, as well as any zoning restriction that apply to
the parcel in the underlying zoning. Unless shown otherwise the RHZ on a channel migration
zone is 50 feet. Other areas not identified on the RHZ, but are located in the floodplain areas
will be subject to the Shoreline Master Plan Critical Areas Appendix B.
(c). When updating the maps the City must consider future conditions and the cumulative effect
from the future land-use changes.
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Title 20—Land Use Code Chapter 20.64: Flooding, Drainage, & Erosion
City of Arlington 20.64 - 7 November 2010
(d). When updating the maps the City must consider identifying and evaluating the risk of
flooding behind 100-year levees within the City jurisdiction based on future conditions and
cumulative effects.
20.64.130 Setbacks from Streams Outside Designated Floodplains.
In any area that is located outside a designated floodplain but where a stream is located, no
building or fill may be located within the buffer as specified in Chapter 20.88 (Environmentally
Critical Areas).
20.64.140 Artificial Obstructions Within Floodways Prohibited.
(a) No artificial obstruction may be located within any floodway, except as provided in
§20.64.150 (Permissible Uses Within Floodways).
(b) For purposes of this section, an artificial obstruction is any obstruction, other than a natural
obstruction, that is capable of reducing the flood carrying capacity of a stream or may
accumulate debris and thereby reduce the flood-carrying capacity of a stream. A natural
obstruction includes any rock, tree, gravel, or analogous natural matter that is an obstruction
and has been located within the floodway by a non-human cause.
20.64.150 Permissible Uses Within Floodways.
(a). Notwithstanding Chapter 20.40 (Permissible Uses) of this Title, no permit to make use of
land within a floodway may be issued unless the proposed use is listed as permissible in Table
20.40-3, the Table of Permissible Uses, Chapter 20.88, Environmentally Critical Areas, and in
the following list:
1. General habitat restoration, farming, pasture, outdoor plant nurseries, horticulture,
forestry, wildlife sanctuary, game farm, and other similar agricultural, wildlife, and related
uses.
2. Ground-level loading areas, parking areas, boat launch, rotary aircraft ports, and other
similar ground-level area uses.
3. Lawns, gardens, play areas, and other similar uses.
4. Golf courses, tennis courts, driving ranges, archery ranges, picnic grounds, parks, hiking
or horseback-riding trails, open space, and other similar private and public recreational
uses.
4.
As indicated in §20.36.060 (Floodplain), the floodplain and floodway districts are established as
overlay districts.
(b) General Development standards to be followed in Special Flood Hazard Area include:
1. If a lot has a buildable site out of the Special Flood Hazard Area,
all new structures shall be located there, when feasible. If the lot
is fully in the floodplain, structures must be located to have the
least impact on salmon.
2. Stormwater and drainage features shall incorporate low impact
development techniques that mimic pre-development hydrologic
conditions, when technically feasible.
3. Creation of new impervious surfaces shall not exceed 10 percent
of the surface area of the portion of the lot in the floodplain unless
mitigation is provided and maintained that functions as “10%
effective impervious surface”.
4. Any loss of floodplain storage shall be avoided, rectified or
compensated for as identified in (20.88.530)
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First line: 0", Numbered + Level: 2 +
Numbering Style: a, b, c, … + Start at: 1 +
Alignment: Left + Aligned at: 0.75" + Tab
after: 1" + Indent at: 1", Tab stops: 0.56",
List tab + Not at 1"
Formatted: List Paragraph, Numbered +
Level: 4 + Numbering Style: 1, 2, 3, … + Start
at: 1 + Alignment: Left + Aligned at: 1.75" +
Tab after: 2" + Indent at: 2"
Title 20—Land Use Code Chapter 20.64: Flooding, Drainage, & Erosion
City of Arlington 20.64 - 8 November 2010
5. Uses that are not permitted in the Protected Area unless shown
not to adversely affect water quality, habitat, etc., include septic
tanks and drain fields, dumping of nay material, hazardous or
sanitary waste landfills: receiving area for toxic or hazardous
waste or other contaminants.
6. The proposed action must be designed and located so that new
structural flood protection is not needed.
7. New road crossing over ESA listed streams within the special
flood hazard area are prohibited unless a concurrence letter from
NMFS or a habitat assessment demonstrating “no adverse affect”
is received.
8. Uses that are allowed in the existing or equivalent zoning and do
not require an up-zoning increasing floodplain development
densities, or participate in a TDR program that results in an
equivalent or greater area of Stillaguamish floodplain to be
protected from development in perpetuity.
20.64.160 Construction Within Floodways and Floodplains Restricted, Habitat Protection
Standards.
Any development occurring in the Floodway or Floodplain will require the issuance of a “Flood
Hazard permit”. A development permit shall be obtained before construction or development
begins within any area of special flood hazard area. The permit shall be for all structures
including manufactured homes, and for all development including fill and other activities as set
forth in this ordinance.
(a) No land use or building permit may be issued for any development within a floodplain until
the permit-issuing authority has reviewed the plans for any such development to assure that:
1. The proposed development is consistent with the need to minimize flood damage, and
2. All public utilities and facilities such as sewer, gas, electrical, and water systems are
located and constructed to minimize or eliminate flood damage, and
3. Adequate drainage is provided to minimize or reduce exposure to flood hazards, and
4. All necessary permits have been received from those agencies from which approval is
required by federal or state law., and
5. The application for a permit to develop in the affected area must include the elevations
of the 10-, 50-, and 100-year floods, where such data are available, and
6. The applicant must record a notice on the title that the property contains land within the
RHZ and/or 100-year floodplain before a permit may be issued, and
7. Any improvements or repairs to existing structures that result in a greater than 10
percent increase of the structure footprint must mitigate for any adverse effects, and
8. Removal of native vegetation must leave 65 percent of the surface area of the portion of
the property in the floodplain with native vegetation in an undeveloped state, and
9. Development in the floodway, RHZ, and CMZ will not adversely affect water quality,
water quantity, flood volumes, flood velocities, spawning substrate, and/or floodplain
refugia for listed salmon, and
10. Development outside the protected area must mitigate for adverse indirect effects on
stormwater, riparian vegetation, bank stability, channel migration, hyporheic zone,
wetland and large woody debris functions, and
4.11.
(b) No building may be constructed and no substantial improvement of an existing building may
take place within any floodway. This includes a prohibition on installing new mobile homes in
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Title 20—Land Use Code Chapter 20.64: Flooding, Drainage, & Erosion
City of Arlington 20.64 - 9 November 2010
an existing mobile home park located in a floodway, even if the park is nonconforming.
(Amended by Ord. 1365, 6/13/05)
(c) Where elevation data is not available either through the Flood Insurance Study, FIRM, or
from another authoritative source the applicant shall obtain, review, and reasonably utilize
any base flood elevation and floodway data available from a Federal, State or other source
(§20.64.060(b) Basis for Establishing the Areas of Special Flood Hazard), applications for
building permits shall be reviewed to assure that proposed construction will be reasonably
safe from flooding. The test of reasonableness is a local judgment and includes use of
historical data, high water marks, photographs of past flooding, etc., where available. Failure
to elevate at least two feet above the highest adjacent grade in these zones may result in
higher insurance rates.
(d) No new residential building may be constructed and no substantial improvement of a
residential building may take place within any floodplain unless the lowest floor (including
basement) of the building or improvement is elevated to or one foot above the base flood
level.
1. Residential accessory structures shall be allowed within floodplains provided they are
firmly anchored to prevent flotation.
2. Anchoring of any accessory buildings may be done by bolting the building to a concrete
slab or by over-the-top ties. When bolting to a concrete slab, one-half inch bolts six feet
on center with a minimum of two per side shall be required. If over-the-top ties are used,
a minimum of two ties with a force adequate to secure the building is required.
(e) No new non-residential building may be constructed and no substantial improvements of a
nonresidential building may take place within any floodplain unless the lowest floor
(including basement) of the building or improvement is elevated or flood-proofed to or one-
foot above the base flood level. Where flood proofing is used in lieu of elevation, a
registered professional engineer or architect shall certify that any new construction or
substantial improvement has been designed to withstand the flood depths, pressure,
velocities, impact, and uplift forces associated with the base flood at the location of the
building and that the walls below the base flood level are substantially impermeable to the
passage of water. (Amended by Ord. 1365, 6/13/05)
(f) For purposes of this section, “substantial improvement” means for a building constructed
prior to the effective date of this title, any repair, reconstruction, or improvement of a building
the cost of which equals or exceeds 50 percent of the market value of the structure either (i)
before the improvement or repair is started or (ii) if the structure has been damaged and is
being restored, before the damage occurred. “Substantial improvement” occurs when the
first alteration on any wall, ceiling, floor, or other structural part of the building commences,
whether or not that alteration affects the external dimensions of the building. The term does
not, however, include either (i) any project for improvement of a structure to comply with
existing state or local health, sanitary, or safety code specifications that are solely necessary
to insure safe living conditions, or (ii) any alteration of a building listed on the National
Register of Historic Places or a State Inventory of Historic Places.
(g) No land use or building permit may be issued for any development within a floodplain until
the permit-issuing authority has reviewed the plans to assure that any new construction or
substantial improvements shall be:
1. Designed (or modified) and adequately anchored to prevent flotation collapse, or lateral
movement of the structure.
2. Constructed with materials and utility equipment resistant to flood damage.
3. Constructed by methods and practices that minimize flood damage.
(h) Notwithstanding any other provision of this title, no mobile home may be located or
relocated within that portion of the floodplain outside of the floodway, unless the following
criteria are met:
Title 20—Land Use Code Chapter 20.64: Flooding, Drainage, & Erosion
City of Arlington 20.64 - 10 November 2010
1. Ground anchors for tie downs are provided.
2. The following tie-down requirements are met:
i. All new construction and substantial improvements shall be anchored to prevent
flotation, collapse, or lateral movement of the structure.
ii. All manufactured homes must likewise be anchored to prevent flotation, collapse, or
lateral movement, and shall be installed using methods and practices that minimize
flood damage. Anchoring methods may include, but are not limited to, use of over-
the-top or frame ties to ground anchors (Reference FEMA’s “Manufactured Home
Installation in Flood Hazard Areas” guidebook for additional techniques). (Amended
by Ord. 1365, 6/13/05)
3. Lots or pads are elevated on compacted fill or by any other method approved by the
administrator so that the lowest habitable floor of the mobile home is at or above the
base flood level.
4. Adequate surface drainage and easy access for mobile home hauler is provided.
5. Load-bearing foundation supports such as piers or pilings must be engineered.
(i) Whenever any portion of a floodplain is filled in with fill dirt, slopes shall be adequately
stabilized to withstand the erosive force of the base flood.
20.64.170 General Standards.
In all areas of special flood hazards, the following standards are required:
(a) Anchoring
1. All new construction and substantial improvements shall be anchored to prevent
flotation, collapse, or lateral movement of the structure.
2. All manufactured homes must likewise be anchored to prevent flotation, collapse, or
lateral movement, and shall be installed using methods and practices that minimize flood
damage. Anchoring methods may include, but are not limited to, use of over-the-top or
frame ties to ground anchors (Reference FEMA’s “Manufactured Home Installation in
Flood Hazard Areas” guidebook for additional techniques).
(b) AH Zone Drainage—Adequate drainage paths are required around structures on slopes to
guide floodwaters around and away from proposed structures.
(c) Construction Materials and Methods
1. All new construction and substantial improvements shall be constructed with materials
and utility equipment resistant to flood damage.
2. All new construction and substantial improvements shall be constructed using methods
and practices that minimize flood damage.
3. Electrical, heating, ventilation, plumbing, and air-conditioning equipment and other
service facilities shall be designed and/or otherwise elevated or located so as to prevent
water from entering or accumulating within the components during conditions of flooding.
20.64.180 Specific Standards for Zones A1-30, AH, and AE
In all areas of special flood hazards where base flood elevation data has been provided (Zones
A1-30, AH, and AE on the community’s FIRM) as set forth in §20.64.060 (Basis for Establishing
the Areas of Special Flood Hazard), the following provisions are required:
(a) Residential Construction
1. New construction and substantial improvement of any residential structure shall have the
lowest floor, including basement, elevated one foot or more above the base flood
elevation.
2. Fully enclosed areas below the lowest floor that are subject to flooding are prohibited, or
shall be designed to automatically equalize hydrostatic flood forces on exterior walls by
allowing for the entry and exit of floodwaters. Designs for meeting this requirement must
Title 20—Land Use Code Chapter 20.64: Flooding, Drainage, & Erosion
City of Arlington 20.64 - 11 November 2010
either be certified by a registered professional engineer or architect or must meet or
exceed the following minimum criteria:
a. A minimum of two openings having a total net area of not less than one square inch
for every square foot of enclosed area subject to flooding shall be provided.
b. The bottom of all openings shall be no higher than one foot above grade.
c. Openings may be equipped with screens, louvers, or other coverings or devices
provided that they permit the automatic entry and exit of floodwaters.
(b) Nonresidential Construction—New construction and substantial improvement of any
commercial, industrial or other nonresidential structure shall either have the lowest floor,
including basement, elevated one foot or more above the base flood elevation; or, together
with attendant utility and sanitary facilities, shall:
1. Be flood-proofed so that below one foot or more above the base flood level the structure
is watertight with walls substantially impermeable to the passage of water;
2. Have structural components capable of resisting hydrostatic and hydrodynamic loads
and effects of buoyancy;
3. Be certified by a registered professional engineer or architect that the design and
methods of construction are in accordance with accepted standards of practice for
meeting provisions of this subsection based on their development and/or review of the
structural design, specifications and plans. Such certifications shall be provided to the
Floodplain Administrator or Building Official.
4. Nonresidential structures that are elevated, not flood-proofed, must meet the same
standards for space below the lowest floor as described in 20.64.180(a)(2) (Specific
Standards for Zones A1-30, AH, and AE—Residential Construction);
5. Applicants flood-proofing nonresidential buildings shall be notified that flood insurance
premiums will be based on rates that are one foot below the flood-proofed level (e.g. a
building flood-proofed to the base flood level will be rated as one foot below).
(c) Manufactured Homes
1. All manufactured homes to be placed or substantially improved on sites:
a. Outside of a manufactured home park or subdivision,
b. In a new manufactured home park or subdivision,
c. In an expansion to an existing manufactured home park or subdivision, or
d. In an existing manufactured home park or subdivision on which a manufactured
home has incurred “substantial damage” as the result of a flood;
e. Shall be elevated on a permanent foundation such that the lowest floor of the
manufactured home is elevated one foot or more above the base flood elevation and
be securely anchored to an adequately designed foundation system to resist
flotation, collapse and lateral movement.
2. Manufactured homes to be placed or substantially improved on sites in an existing
manufactured home park or subdivision that are not subject to the above manufactured
home provisions be elevated so that either:
a. The lowest floor of the manufactured home is elevated one foot or more above the
base flood elevation, or
b. The manufactured home chassis is supported by reinforced piers or other foundation
elements of at least equivalent strength that are no less than 36 inches in height
above grade and be securely anchored to an adequately designed foundation
system to resist flotation, collapse, and lateral movement.
(d) Recreational Vehicles—Recreational vehicles placed on sites are required to either:
1. Be on the site for fewer than 180 consecutive days,
2. Be fully licensed and ready for highway use, on its wheels or jacking system, is attached
to the site only by quick disconnect type utilities and security devices, and has no
permanently attached additions; or
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City of Arlington 20.64 - 12 November 2010
3. Meet the requirements of Subsection 20.64.180(c) Specific Standards for Zones A1-30,
AH, and AE—Manufactured Homes) above and the elevation and anchoring
requirements for manufactured homes.
20.64.190 Specific Standards for Designated Regulatory Floodways.
Located within areas of special flood hazard established in §20.64.060 (Basis for Establishing
the Areas of Special Flood Hazard) are areas designated as floodways. Since the floodway is
an extremely hazardous area due to the velocity of floodwaters that carry debris, potential
projectiles, and erosion potential, the following provisions apply:
1. Prohibit encroachments, including fill, new construction, substantial improvements, and
other development unless certification by a registered professional engineer is provided
demonstrating through hydrologic and hydraulic analyses performed in accordance with
standard engineering practice that the proposed encroachment would not result in any
increase in flood levels during the occurrence of the base flood discharge.
2. Construction or reconstruction of residential structures is prohibited within designated
floodways, except for (i) repairs, reconstruction, or improvements to a structure which do
not increase the ground floor area; and (ii) repairs, reconstruction or improvements to a
structure, the cost of which does not exceed 50 percent of the market value of the
structure either, (A) before the repair, or reconstruction is started, or (B) if the structure
has been damaged, and is being restored, before the damage occurred. Any project for
improvement of a structure to correct existing violations of state or local health, sanitary,
or safety code specifications which have been identified by the local code enforcement
official and which are the minimum necessary to assure safe living conditions or to
structures identified as historic places shall not be included in the 50 percent.
3. If Subsection 1 is satisfied, all new construction and substantial improvements shall
comply with all applicable flood hazard reduction provisions of §20.64.180 through §240.
20.64.200 Specific Standards For Shallow Flooding Areas (AO Zones)
Shallow flooding areas appear on FIRMs as AO zones with depth designations. The base flood
depths in these zones range from 1 to 3 feet above ground where a clearly defined channel
does not exist, or where the path of flooding is unpredictable and where velocity flow may be
evident. Such flooding is usually characterized as sheet flow. In these areas, the following
provisions apply:
1. New construction and substantial improvements of residential structures and
manufactured homes within AO zones shall have the lowest floor (including basement)
elevated above the highest adjacent grade to the structure, one foot or more above the
depth number specified in feet on the community’s FIRM (at least two feet above the
highest adjacent grade to the structure if no depth number is specified).
2. New construction and substantial improvements of nonresidential structures within AO
zones shall either:
a. Have the lowest floor (including basement) elevated above the highest adjacent
grade of the building site, one foot or more above the depth number specified on the
FIRM (at least two feet if no depth number is specified); or
b. Together with attendant utility and sanitary facilities, be completely flood proofed to
or above that level so that any space below that level is watertight with walls
substantially impermeable to the passage of water and with structural components
having the capability of resisting hydrostatic and hydrodynamic loads and effects of
buoyancy. If this method is used, a registered professional engineer or architect as in
Subsection 20.64.180(b)3 Specific Standards for Zones A1-30, AH, and AE) shall
certify compliance.
Title 20—Land Use Code Chapter 20.64: Flooding, Drainage, & Erosion
City of Arlington 20.64 - 13 November 2010
3. Require adequate drainage paths around structures on slopes to guide floodwaters
around and away from proposed structures.
4. Recreational vehicles placed on sites within AO Zones on the community’s FIRM either:
a. Be on the site for fewer than 180 consecutive days,
b. Be fully licensed and ready for highway use, on its wheels or jacking system, is
attached to the site only by quick disconnect type utilities and security devices, and
has no permanently attached additions; or
c. Meet the requirements of Subsections 1 and 3 above and the anchoring
requirements for manufactured homes (Subsection 20.64.170(a)2, General
Standards).
20.64.210 Encroachments
In areas where a regulatory floodway has not been designated, no new construction, substantial
improvements, or other development (including fill) shall be permitted within Zones A1-30 and
AE on the community’s FIRM, unless it is demonstrated that the cumulative effect of the
proposed development, when combined with all other existing and anticipated development, will
not increase the water surface elevation of the base flood more than one foot at any point within
the community.
20.64.220 Special Provisions for Subdivisions.
(a) All subdivision proposals shall be consistent with the need to minimize flood damage.
(b) All subdivision proposals shall have public utilities and facilities, such as sewer, gas,
electrical, and water systems located and constructed to minimize or eliminate flood
damage.
(c) All subdivision proposals shall have adequate drainage provided to reduce exposure to flood
damage.
(d) Where base flood elevation data has not been provided or is not available from another
authoritative source, it shall be generated for subdivision proposals and other proposed
developments that contain at least 50 lots or 5 acres (whichever is less).
(e) All subdivisions are subject to use and construction restrictions contained in §20.64.140
(Artificial Obstructions Within Floodways Prohibited), §20.64.150 (Permissible Uses Within
Floodways), §20.64.160 (Construction Within Floodways and Floodplains Restricted), and
§20.64.230 (Utility Systems in Floodways and Floodplains) if any portion of the land to be
subdivided lies within a floodway or floodplain.
(f) Final plat approval for any subdivision containing land that lies within a floodway or
floodplain may not be given unless the plat shows the boundary of the floodway or floodplain
and contains in clearly discernible print the following statement: “Use of land within a
floodway or floodplain is substantially restricted by Title 20, Chapter 20.64 of the Arlington
Municipal Code.”
(g) Subject to the following sentence, a conditional use permit or final plat approval for any
subdivision may not be given if:
1. The land to be subdivided lies within a zone where residential uses are permissible and
it reasonably appears that the subdivision is designed to create residential building lots,
and
2. Any portion of one or more of the proposed lots lies within a floodway or floodplain, and
3. It reasonably appears that one or more lots described in Subdivisions (1) and (2) of this
subsection could not practicably be used as a residential building site because of the
restrictions set forth in §20.64.160 (Construction Within Floodways and Floodplains
Restricted), §20.64.170 (General Standards), and §20.64.180 (Specific Standards for
Zones A1-30, AH, and AE).
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Title 20—Land Use Code Chapter 20.64: Flooding, Drainage, & Erosion
City of Arlington 20.64 - 14 November 2010
20.64.230 Utility Systems in Floodways and Floodplains.
Whenever any portion of a proposed development is located within a floodway or floodplain, the
agency or agencies responsible for certifying to the city the adequacy of the utility systems for
the development (as set forth in Chapter 20.60) shall be informed by the developer that a
specified area within the development lies within a floodway or floodplain. Thereafter, said
agency shall certify, prior to approval of the proposed system, that:
1. All new and replacement water supply systems are designed to minimize or eliminate
infiltration of flood waters into the systems;
2. Any proposed water wells are located on high ground that is not in the floodway (WAC
173-160-171);
3. New and replacement sanitary sewage systems are designed to minimize or eliminate
infiltration of flood waters into the systems and discharges from the systems into flood
waters; and,
4. On-site waste disposal systems are located to avoid impairment to them or
contamination from them during flooding;and,
4.5. All new utilities would be located outside of the Channel Migration Zone..
20.64.240 Critical Facility.
Construction of new critical facilities shall be, to the extent possible, located outside the limits of
the Special Flood Hazard Area (SFHA) (100-year floodplain). Construction of new critical
facilities shall be permissible within the SFHA if no feasible alternative site is available. Critical
facilities constructed within the SFHA shall have the lowest floor elevated three feet or to the
height of the 500-year flood, whichever is higher. Access to and from the critical facility should
also be protected to the height utilized above. Flood-proofing and sealing measures must be
taken to ensure that toxic substances will not be displaced by or released into floodwaters.
Access routes elevated to or above the level of the base flood elevation shall be provided to all
critical facilities to the extent possible.
20.64.250 Additional Duties of Administrator Related to Flood Insurance and Flood Control,
including information to be obtained and maintained.
The administrator shall:
(a) For the purpose of the determination of applicable flood insurance risk premium rates within
Zone A on the city’s Flood Insurance Rate Map provided by the U.S. Federal Emergency
Management Agency:
1. Obtain and record the elevation (in relation to mean sea level) of the lowest floor
(including basement) of all new or substantially improved structures including to which
level it was flood-proofed; and (Amended by Ord. 1365, 6/13/05)
2. Obtain, for all structures that have been flood-proofed (whether or not such structures
contain a basement) the elevation (in relation to mean sea level in the FEMA datum) to
which the structure was flood-proofed; and
3. Maintain the floodproofing certifications found in others sections of this ordinace; and
2.4. For development that occurs outside of the protected area the city will track
projects which have been issued floodplain development permits, including effects to
flood storage and fish habitat and mitigation provided.
3.5. Maintain a record of all such information for public inspection.
(b) Notify, in riverine situations, adjacent communities, the U.S. Army Corps of Engineers, the
Washington State Department of Fish and Wildlife, and any effected diking or drainage
districts prior to any alteration or relocation of a watercourse, and submit copies of such
notification to the Federal Insurance Administrator.
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City of Arlington 20.64 - 15 November 2010
(c) Ensure that the flood-carrying capacity within the altered or relocated portion of any
watercourse is maintained and within the same sub-basin so carrying capacity is not
diminished.
(d) Maintain the records of all appeal actions and report any variances to the Federal Insurance
Administration upon request.
20.64.260 Variances from Requirements.
(a) Generally, the only condition under which a variance from the elevation standard may be
issued is for new construction and substantial improvements to be erected on a lot of one-
half acre or less in size contiguous to and surrounded by lots with existing structures
constructed below the base flood level, providing items (1-11) in Subsection (i) have been
fully considered. As the lot size increases, the technical justification required for issuing the
variance increases.
(b) Variances may be issued for the reconstruction, rehabilitation, or restoration of structures
listed on the National Register of Historic Places or the State Inventory of Historic Places,
without regard to the procedures set forth in this section.
(c) Variances shall not be issued within a designated floodway if any increase in flood levels
during the base flood discharge would result, or the development may eventually require
additional structural flood protection.
(d) Variances shall only be issued upon a determination that the variance is the minimum
necessary, considering the flood hazard, to afford relief.
(e) Variances shall only be issued upon:
1. A showing of good and sufficient cause;
1.2. The submittal, review and approval of a Biological Assessment;
2.3. A determination that failure to grant the variance would result in exceptional
hardship to the applicant;
3.4. A determination that the granting of a variance will not result in increased flood
heights, additional threats to public safety, extraordinary public expense, create
nuisances, cause fraud on or victimization of the public, or conflict with existing local
laws or ordinances.
(f) Variances as interpreted in the National Flood Insurance Program are based on the general
zoning law principle that they pertain to a physical piece of property; they are not personal in
nature and do not pertain to the structure, its inhabitants, economic or financial
circumstances. They primarily address small lots in densely populated residential
neighborhoods. As such, variances from the flood elevations should be quite rare.
(g) Variances may be issued for nonresidential buildings in very limited circumstances to allow a
lesser degree of flood-proofing than watertight or dry-flood-proofing, where it can be
determined that such action will have low damage potential, complies with all other variance
criteria except Subsection (i)1, and otherwise complies with §20.64.170(a) General
Standards), 20.64.170(c), and §20.64.230 (Utility Systems in Floodways and Floodplains).
(h) Any applicant to whom a variance is granted is hereby notified that the structure will be
permitted to be built with a lowest floor elevation below the base flood elevation and that the
cost of flood insurance will be commensurate with the increased risk resulting from the
reduced lowest floor elevation.
(i) In granting a variance, in addition to the findings of §20.20.030 (Variances), the decision-
maker shall consider and make findings concerning all technical evaluations, all relevant
factors, standards specified in other sections of this chapter, and (including the degree to
which the applicant proposes to mitigated impacts to) the following:
1. The danger that materials may be swept onto other lands to the injury of others;
2. The danger to life and property due to flooding or erosion damage;
2.3. The impact to ESA listed species;
Field Code Changed
Title 20—Land Use Code Chapter 20.64: Flooding, Drainage, & Erosion
City of Arlington 20.64 - 16 November 2010
3.4. The susceptibility of the proposed facility and its contents to flood damage and
the effect of such damage on the individual owner;
4.5. The importance of the services provided by the proposed facility to the
community;
5.6. The necessity to the facility of a waterfront location, where applicable;
6.7. The availability of alternative locations for the proposed use which are not subject
to flooding or erosion damage;
7.8. The compatibility of the proposed use with existing and anticipated development;
8.9. The relationship of the proposed use to the comprehensive plan and flood plain
management program for that area;
9.10. The safety of access to the property in times of flood for ordinary and emergency
vehicles;
10.11. The expected heights, velocity, duration, rate of rise, debris and sediment
transport of the flood waters and the effects of wave action, if applicable, expected at the
site; and,
11.12. The costs of providing governmental services during and after flood conditions,
including maintenance and repair of public utilities and facilities such as sewer, gas,
electrical, and water systems, and streets and bridges.
(j) Upon consideration of the factors of Subsection (b) and the purposes of this ordinance, the
decision-maker may attach such conditions to the granting of a waiver, as it deems
necessary to further the purposes of this chapter.
Part II. Drainage, Erosion Control, Storm Water Management
20.64.300 Stormwater Management.
All stormwater systems shall be in compliance with AMC 13.28, Stormwater Management.
). and Floodway Districts. of Community Development Director, Design Review Board, Planning
Commission or Hearing Examiner Decisions and Floodway Districts Established
Legend
Riparian Boundary
Channel Subject to Migration*
FEMA Floodplain
FEMA Floodway
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South Fork Stillaguamish River
E DIVISION ST
W BURKE AVE
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N WEST AVE
E DIVISION ST
SR 9
SR 530
SR 530
SR 530
City of Arlington Floodplain/FEMA
Streams,Riparian Habitat Zone,Floodplain and Floodway:Old Town and Island Crossing
Maps and GIS data are distributed “AS-IS” withoutwarranties of any kind, either express or implied,including but not limited to warranties of suitability fora particular purpose or use. Map data are compiledfrom a variety of sources which may contain errorsand users who rely upon the information do so at theirown risk. Users agree to indemnify, defend, and holdharmless the City of Arlington for any and all liability ofany nature arising out of or resulting from the lack ofaccuracy or correctness of the data, or the use of thedata presented in the maps.
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RiparianHZ_11x17_10.mxd
05/24/2011
Date:
File:
Cartographer:
DRAFT
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Portage Creek
South Slough
SR 530
PIONEER HWY E SMOKEY POINT
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SMOKEY POINT
BLVD
SMOKEY POINT BLVD
´0 0.1 0.20.05 Miles
City Limits
City UGA
Local roads
Streams
Rivers
Ponds
DRAFT
*'Channels subject to migration' recieved from Snohomish County, 2010.Draft dFIRM floodplain and floodway data provided by FEMA, 2009
Streams and waterbodies courtesy of Snohomish County Dept of InformationSystems, June 2009.
Aerials taken in June 2009.
City of Arlington
Council Agenda Bill
AGENDA ITEM:
ATTACHMENT G
COUNCIL MEETING DATE:
July 11, 2011
SUBJECT:
Amended Interlocal Agreement to jointly fund
lobbying activities for the SR 9 Coalition
DEPARTMENT OF ORIGIN:
Executive
Contact: Allen Johnson, 360-403-3441
ATTACHMENTS:
- Amended Interlocal Agreement to jointly fund the costs of lobbying activities for the SR
9 Coalition and proposed Scope of Work with Exhibit A1.
EXPENDITURES REQUESTED:
BUDGET CATEGORY:
LEGAL REVIEW:
DESCRIPTION:
As previously discussed with the Council, we entered into an Interlocal Agreement to jointly
fund the costs of lobbying activities for the SR 9 Coalition. The parties to the agreement are the
cities of Arlington, Lake Stevens, Marysville, and Snohomish.
Upon execution of this amended Interlocal Agreement, the City of Marysville will continue the
professional services agreement with Strategies 360 for the purpose of obtaining effective
lobbying services to help secure funding for the Highway 9 improvements. The Interlocal
provides for an equal split of the lobbying costs between the four cities.
HISTORY:
The SR 9 Coalition was formed in order to secure funding for the necessary improvements to
SR 9 and ensure that our best interests are represented in the decision-making processes of the
Washington State Legislature and the Washington State Department of Transportation. Council
member Byrnes and Public Works Director Jim Kelly serve on the SR 9 Coalition.
ALTERNATIVES:
RECOMMENDED ACTION:
Council will be asked to approve the Amended Interlocal Agreement at the July 18, 2011
Council meeting.
ILA Lobbying Services First Amend Exhibit A1 2011-2012 Page 1 of 5
S-10-040 Hwy9/ILA Lobbying Services First Amend Exhibit A1 2011-2012
FIRST AMENDMENT TO INTERLOCAL AGREEMENT
FOR LOBBYING SERVICES
ADDING “EXHIBIT A1 JULY 2011 – MARCH 2012
PROPOSED SCOPE OF WORK – SR 9 COALITION”
THIS FIRST AMENDMENT TO INTERLOCAL AGREEMENT FOR LOBBYING
SERVICES (“Amendment”) is made and is entered into by and between the City of
Arlington, a Washington municipal corporation (“Arlington”), the City of Marysville, a
Washington municipal corporation (“Marysville”), the City of Lake Stevens, a Washington
municipal corporation (“Lake Stevens”), and the City of Snohomish, a Washington
municipal corporation (“Snohomish”) (collectively referred to hereinafter as the “Cities”)
as follows:
WHEREAS, pursuant to RCW 39.34, the Cities entered into the INTERLOCAL
AGREEMENT FOR LOBBYING SERVICES (“Agreement”) dated 10/12/2010; and,
WHEREAS, the Cities have agreed to add to existing “Exhibit A” of the
Agreement, the additional “Exhibit A1 July 2011 – March 2012 Proposed Scope of Work –
SR 9 Coalition” necessitating the amendment of the Agreement.
NOW, THEREFORE, in consideration of the mutual covenants, conditions and
promises contained herein, Cities mutually agree as follows:
1. “Exhibit A1 July 2011 – March 2012 Proposed Scope of Work – SR 9
Coalition” is adopted and added to the Agreement which shall be effective July 1, 2011 and
shall be as attached hereto and incorporated by this reference.
2. Subject to the mutual written consent of the City Administrators, City Managers
or Chief Administrative Officers of all parties hereto, the scope may be periodically revised
to reflect current needs without further action of the respective City Councils so long as the
revised scope does not result in exceedance of the originally authorized $45,000 contract
ILA Lobbying Services First Amend Exhibit A1 2011-2012 Page 2 of 5
S-10-040 Hwy9/ILA Lobbying Services First Amend Exhibit A1 2011-2012
fee.
3. This First Amendment may be executed in counterparts, each which shall be
considered same as an original.
4. Except as provided herein, all other terms and conditions of the INTERLOCAL
AGREEMENT FOR LOBBYING SERVICES thereto remain in place and shall be
unchanged by this agreement.
IN WITNESS WHEREOF, the parties have hereunto set their hands and
seals this _____ day of ________________, 2011.
CITY OF ARLINGTON CITY OF LAKE STEVENS
____________________________ ___________________________
Margaret Larson, Mayor Vern Little, Mayor
ATTEST/AUTHENTICATED: ATTEST/AUTHENTICATED:
____________________________ _____________________________
Kristin Banfield, City Clerk Norma Scott, City Clerk
APPROVED AS TO FORM APPROVED AS TO FORM
______________________________ ____________________________
Steven Peiffle, City Attorney Grant K. Weed, City Attorney
Per Waiver
CITY OF MARYSVILLE CITY OF SNOHOMISH
____________________________ ___________________________
Jon Nehring, Mayor Larry Bauman, City Manager
ATTEST/AUTHENTICATED: ATTEST/AUTHENTICATED:
____________________________ _____________________________
ILA Lobbying Services First Amend Exhibit A1 2011-2012 Page 3 of 5
S-10-040 Hwy9/ILA Lobbying Services First Amend Exhibit A1 2011-2012
April O’Brien, Deputy City Clerk Torchie Corey, City Clerk
APPROVED AS TO FORM APPROVED AS TO FORM
______________________________ ____________________________
Grant K. Weed, City Attorney Grant K. Weed, City Attorney
Per waiver Per Waiver
ILA Lobbying Services First Amend Exhibit A1 2011-2012 Page 4 of 5
S-10-040 Hwy9/ILA Lobbying Services First Amend Exhibit A1 2011-2012
Exhibit A1
July 2011 – March 2012
Proposed Scope of Work – SR 9 Coalition
July thru December 2011
1. Meet with staff at WSDOT, PSRC and SCCIT to get a direct gauge of the situation
and begin the persuasive work that will lead to including funding for SR 9 in the
proposed 2012 transportation package.
2. Attend SCCIT meetings and advocate, where appropriate, for funding for SR 9.
3. Participate, to the extent possible, in Transportation Partnership meetings and
activities.
4. Meet with key members of the Legislature, including Sen. Haugen, Rep. Clibborn,
Rep. Liias, Rep. Armstrong, and Rep. Billig to both advocate for SR 9 funding and
to stay abreast of discussions regarding a potential funding package for
transportation, which we expect to be a key subject during the 2012 Legislative
session.
5. Meet with legislators from districts that include SR 9.
6. Advise SR 9 Coalition of timing for federal appropriations requests, review draft of
funding proposals.
7. Provide monthly written summary.
January thru March 2012
1. Monitor and report on legislative hearings, particularly those involving
transportation projects and budgets. Advise of opportunities for testifying on bills.
2. Prep SR 9 representatives for testifying at legislative hearings.
3. Meet occasionally with key legislative representatives and legislators along SR 9 to
remind them of the need for funding.
4. Prep SR 9 Coalition members for meetings in Washington DC with Congressional
Members and staff regarding funding for SR 9.
5. Provide monthly written summary.
This effort represents approximately 10 hours of work per month, perhaps more during the
Legislative session. We propose doing this work at the same level/price ($1,750 per
month) for July through December. In November of 2011, we should discuss what level of
effort the group wants to pay for during the 2012 Legislative session.
ILA Lobbying Services First Amend Exhibit A1 2011-2012 Page 5 of 5
S-10-040 Hwy9/ILA Lobbying Services First Amend Exhibit A1 2011-2012
In terms of Strategies 360 personnel, Al Aldrich will do most of the work with legislators
and will be the registered lobbyist. Al will be the lead on meeting with the agencies and
organizations identified in the scope of work (WSDOT, PSRC, etc.) Al and Mary
Swenson both will be involved in most of the meetings with the Cities in the SR 9
Coalition, either in person or by phone. Mary will also participate in some informational
meetings with legislators and meetings with other organizations (WSDOT, PSRC, etc.).
Other personnel at Strategies 360 will be involved on occasion; for example, other staff
who work in Olympia will be consulted for strategic ideas and information, our creative
director will be involved in designing and producing any written materials, and our staff
who work frequently with coalitions and campaigns will be utilized for assistance with
work in that area.
City of Arlington
Council Agenda Bill
AGENDA ITEM:
ATTACHMENT H
COUNCIL MEETING DATE:
July 11, 2011
SUBJECT:
Review of Park Naming Criteria and
Procedure Policy
DEPARTMENT OF ORIGIN:
Executive
Contact: Sarah Higgins, 360-403-3448
ATTACHMENTS: Park Naming Criteria and Procedure adopted by City Council.
EXPENDITURES REQUESTED: -0-
BUDGET CATEGORY: N/A
LEGAL REVIEW: City Attorney Reviewed Resolution
DESCRIPTION: Attached is the Park Naming Policy that has been adopted by resolution on
July 25, 2000, and amended on November 15, 2010 for review.
The City is now soliciting names from the public for the property known as “Country Charm
Conservation Area”. These suggestions will go to the PARC meeting on July 26, 2011 for
review. The PARC commission will forward their recommendation to City Council.
HISTORY: On November 15, 2010, City Council adopted by resolution the attached amended
Park Naming Policy. At that time, the Park, Arts, and Recreation Commission recommended
that the Park Naming Policy be revised so that it was less detailed in regards to who must be
contacted when considering names for parks. PARC recommended that solicitation for names
be done through the local newspaper, TV channel 21, and the City website. The Council
reviewed the policy at the workshop on November 8, 2010, and adopted the resolution on
November 15.
ALTERNATIVES: N/A
RECOMMENDED ACTION:
N/A