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Exhibit 9 - Approved Water and Sewer Availability
i WATER AND SEWER AVAILABILITY REQUEST Community and Economic Development City of Arlington• 18204 591h Avenue NE•Arlington,WA 98223 • Phone(360)403-3551 Submittal Requirements: 1 Complete Application 2 8-1/2"x 11"Site Plan/Sketch of the Proposal Type of Request: ❑ Water Only ❑ Sewer Only ❑✓ Water and Sewer Location/Legal Property Address: 8014 172nd St NE Lot#: Parcel ID No(s): 31052500200600&4 others-see attached Subdivision:Lindsay Project 1 Project Scope of Work: 171 Single Family Lot Subdivision on 32.26 acres Owner Name: see attached list Office No.: Email Address: Cell No.: Mailing Address: City: State: Zip: Owners Agent: MJS Investors Office No.: 425.559.2726 Email Address: robr@mjsinvestors.com Cell No.: Mailing Address: 11400 SE 8th St city: Bellevue State: WA zip:98004 RESIDENTIAL INFORMATION ❑Proposed Single Family Residence ❑Existing Single Family Residence ❑Accessory Dwelling Unit ❑Proposed Multi-Family Residence:#of Units #of Buildings ❑✓ Residential Plat:#of Lots 171 COMMERCIAL INFORMATION ❑ Binding Site Plan/Plat:#of Lots #of Phases #of Buildings Total Square Footage TYPE OF COMMERCIAL USE ❑Hotel/Motel ❑Food Service ❑ Medical/Dental ❑Office ❑ Retail ❑Vehicle Service ❑Warehouse/Storage ❑ Industrial ❑ Other(specify): Commercial Water Usage: Monthly Estimation: Gallons WATER,SEPTIC SYSTEM AND FIRE Is there an existing Well on the property? Yes ❑No Is there an existing Septic System on-site? ❑✓ Yes ❑No Water Meter Size Requested? ❑r 5/8" ❑ 1" ❑ 1.5" ❑ 2" ❑3" ❑4" ❑6" Type of Fire Protection Requested? Fire Sprinkler System ❑r Fire Hydrant ❑Unknown I,the undersigned,request City of Arlington Utilities Division to certify willingness to provide water and/or sewer as indicated. The above information is complete and accurate to the best of my knowledge. I understand that any changes to the above information must be reported immediately to the City ofArlington Utilities Division as a condition of Utility Availability approval. Digitally signed by Rob Rob Risinger Date:2026.02.0415:53:14 oeoo' Rob Risinger 2/4/26 Signature(owner/agent) Print Name Date Page 1 of 2 REV02.2022 TO BE COMPLETED BY THE CITY OF ARLINGTON CITY OF ARLINGTON UTILITIES DIVISION - PRELIMINARY INFORMATION I CERTIFICATION This non-binding preliminary commitment is only valid for the above referenced property in accordance with City of Arlington policies and for only 18 months. NO A water main or other capital facility improvement ❑ is required; ® is not required (If required, refer to below conditions) Water is presently available from City of Arlington to service the above referenced property and YES specified number of connections per the below conditions and upon payment of applicable connection fees and charges. Fire Flow Estimate. STATIC PRESSURE 60 PSI RESIDUAL PRESSURE 42 PSI FLOW 3,120 GPM NO A sanitary sewer main or other capital facility improvement ❑ is required; ® is not required (If required, refer to attached conditions) Sanitary sewer is presently available from City of Arlington to service the above referenced YES property and specified number of connections per the below conditions and upon payment of applicable connection fees and charges. Other: Water and Sewer service is a ailable at this location per the below conditions. Approved By: Date: Oy o Z leoa EXPIRES 18 MONTHS FROM DATE OF ISSUE COMMENTS: 1. Water service is available for this project. Please coordinate with the Arlington City Engineer for water service line connection, meter locations, backflow protection, utility easements, on- site water main alignment, and any other City of Arlington water supply requirements. 2. A sanitary sewer flow analysis was prepared by RH2 Consulting for the Lindsay Development, a copy of that analysis is attached. 3. Sewer service is available for this project; connections shall be made per preliminary site sewer utility plan at sanitary sewer manholes MH-1864 and MH-1820. No additional off-site improvements are needed. Please coordinate with the Arlington City Engineer for specifics pertaining to sewer utility easements, development on-site sewer main alignment, required pipe size and slope, monitoring manhole location (if needed), pretreatment requirements, and any other City of Arlington sewer requirements. 4. Any wells and septic systems on the development property are to be abandoned per Arlington Municipal Codes 13.04.140 and 13.08.160 as a condition of service. 5. Water and Sewer system improvements shall be designed and constructed in accordance with City of Arlington Design and Construction Standards. 6. Fire flow data is from water model node 2025-J-803 at the south side of the SR-531 and 80th Drive intersection. LINDSAY PROJECT 1 OWNERSHIP 310525-002-006-00 William &Joan Lindsay Lindsay Investments, LLC 8326 172"d St NE—site address Arlington, WA 98223 242 Burke Dr.—Owner/Taxpayer address per Assessor's site Camano Island, WA 98282 310526-001-001-00 Joe and Patricia Matthias 8210 172"d St NE Arlington, WA 98223 310526-001-002-00 Virl and Dianna Basim 8014 172"d St. Arlington, WA 98223 310526-001-022-00 & 310526-001-023-00 John & Kelly Markezinis 8118 172"d St NE Arlington, WA 98223 � Y ` 1 'Vt4 .t• RR , - Gleneagle ALI Pik.. Y! 1 Is .� r� a, d - • ri- /�j 't 531 _ Li•ndsaayr is Deuelot merit r`w tTiF ir. . City of Arlington = m Lindsay Development Sewer Manholes N Lindsay Property Wastewater Wastewater Route 1 Lift Station Connection Routes JWastewater Route 2 Scale: File: Aerial captured in 2024. WastewaterLayouts/ p 1 inch=1,000 ft Connect8x11 2026 This tlsw isprov+ded as ii vnthout warranty of any kind-The entire risk as to the results and performance of the data is assumed Lindsa y — hy you.Should the data trove defective.you assume the entire cost of all necessary servicing,repair,at correction.These data and corresponding attributes are not to be used for design purposes.Further,the Coy of Arlington does not warrant.quafantee,or make any representations regarding the use of,or resulls from the use of the data interms of correctness,accuracy,rekabWNy, Date: Cartographer: currentness,a otherwise;and you rely on din data and resuhs solely of your own risk.There are known gaps and inaccuracies in - Ili, cunertf data Sot and the provided nlormation should he considered a draft and in,progress work Wdshngton State law,Ch 4/2/2026 a kc a2.56 RCW,prohdAs state and local agencies from providing access to lists of ndiwduals intended for use for commercial purposes and thus,no commercial use may he made of any Oahe Comprising WS of nidmduats contained herein City of Arlington Lindsay Subarea Sewer Hydraulic Analyses 23-26 On-Call Water & Sewer System Engineering Services Task 1 Results ID Label Diameter(in) Material Slope(Calculated)(%) Manning's n Start Node Stop Node Velocity(ft/s) Flow(gal/min) Capacity(Full Flow)(gal/min) Flow/Capacity(%) Depth(Middle)(ft) Depth/Diameter(%) 3379 P-749 8 PVC 1.77 0.01 MH-1865 MH-1864 3.96 105.2 938.3 11.2 0.22 34 3378 P-755 8 PVC 0.38 0.01 MH-1864 MH-1863 2.31 108.2 436.9 24.8 0.23 34 3377 P-748 8 PVC 1.12 0.01 MH-1863 MH-1862 3.4 109.28 744.6 14.7 0.23 34 3376 P-757 8 PVC 2.04 0.01 MH-1862 MH-1861 4.21 109.56 2,007.1 10.9 0.23 34 3375 P-2421 8 PVC 6.58 0.01 MH-1861 MH-1860 6.39 110.32 1,808.0 6.1 0.27 41 3374 P-739 8 PVC 3.00 0.01 MH-1860 MH-1859 5.83 210.16 1,221.2 17.2 0.25 38 3373 P-730 8 PVC 2.67 0.01 MH-1859 MH-1858 5.58 210.16 1,151.3 18.3 0.26 38 3372 P-740 8 PVC 8.09 0.01 MH-1858 MH-658 8.3 210.16 2,005.9 10.5 0.23 35 3353 P-773 8 PVC 1.64 0.01 MH-658 MH-657 4.69 210.16 903.9 23.3 0.32 48 3352 P-772 8 PVC 6.56 0.01 MH-657 MH-841 7.73 211.12 1,806.0 11.7 0.32 49 3356 P-716 8 PVC 0.59 0.01 MH-841 MH-835 3.28 222.12 540.2 41.1 0.31 47 3357 P-715 8 PVC 0.51 0.01 MH-835 MH-828 3.12 222.12 505.6 43.9 0.32 48 3359 P-696 8 PVC 0.56 0.01 MH-828 MH-666 3.23 222.12 528.9 42.0 0.32 47 3369 P-1960 8 PVC 0.56 0.01 MH-666 MH-667 3.23 222.12 529.2 42.0 0.33 50 3368 P-1959 8 PVC 0.52 0.01 MH-667 MH-761 3.17 23_1.72 508.5 45.6 0.34 51 3346 P-734 8 PVC 0.73 0.01 MH-761 MH-843 3.66 245.6 604.4 40.6 0.35 52 3339 P-778 8 PVC 0.53 0.01 MH-843 MH-743 3.25 246.92 514.9 48.0 0.35 53 3833 P-3190 8 PVC 0.44 0.01 MH-743 MH-3342 3.04 252.52 466.9 54.1 0.35 53 5 3834 P-3134 8 PVC 1.95 0.01 MH-3342 MH-769 5.27 254.56 984.5 25.9 0.35 3338 P-779 8 PVC 5.87 0.01 MH-769 MH-775 7.83 255.36 1,707.8 15.0 0.35 53 3337 P-1560 8 PVC 8.24 0.01 MH-775 MH-656 8.83 256.28 2,023.6 12.7 0.36 53 3835 P-3135(1) 8 PVC 1.29 0.01 MH-656 MH-663 4.56 257.84 801.6 32.2 0.36 54 3322 P-2266 8 PVC 0.59 0.01 MH-663 MH-671 3.42 259.96 540.4 48.1 0.36 54 3321 P-1937 8 PVC 0.49 0.01 MH-671 MH-691 3.2 261.84 494.8 52.9 0.36 54 3317 P-1992 8 PVC 0.69 0.01 MH-691 MH-681 3.64 264.12 584.9 45.2 0.37 55 3310 P-2485 8 PVC 3.31 0.01 MH-681 MH-2124 6.57 284.28 1,283.6 22.1 0.37 56 3309 P-1950 8 PVC 5.33 0.01 MH-2124 MH-682 7.81 284.44 1,627.6 17.5 0.38 56 3307 P-1935 8 PVC 5.45 0.01 MH-682 MH-700 7.89 286.4 1,646.3 17.4 0.38 56 3308 P-1952 8 PVC 5.48 0.01 MH-700 MH-693 7.91 286.92 1:650 4 17.4 0.28 42 3414 P-661 8 PVC 2.29 0.01 MH-693 MH-684 5.77 287.24 1,066.1 26.9 0.38 57 3431 P-654 8 PVC 1_.34 0.01 MH-684 MH-639 4.79 292.08 817.6 35.7 0.38 57 3430 P-623 8 PVC 4.25 0.01 MH-639 MH-738 7.29 297.04 1,454.0 20.4 0.38 58 3831 P-2384 8 PVC 2.32 0.01 MH-738 MH-3341 5.86 297.68 1,073.8 27.7 0.39 59 3832 P-3189 8 PVC 3.38 0.01 MH-3341 _ _ M_H- 12 _757 6.86 323.16 1,295.6 . 0.4 60 3429 P-852 8 PVC 13.93 0.01 MH-757 MH-767 11.49 329.64 2,631.3 .5 0.41 61 3424 P-2487 8 PVC 7.86 0.01 MH-767 MH-772 9.37 330.08 1,976.3 16.7 0.41 61 3422 P-1941 8 PVC 3.11 0.01 MH-772 MH-777 6.7 331 1,242.4 26.6 0.45 67 7144 P-1767 12 PVC 0.22 0.01 MH-777 MH-111,MH-2019 2.75 476.32 975.0 48.9 0.48 48 City of Arlington Lindsay Subarea Sewer Hydraulic Analyses 23-26 On-Call Water & Sewer System Engineering Services Task 2 Results ID label Diameter(in) Material Slope(Calculated)(%) Manning's n Start Node Stop Node Velocity(ft/s) Flow(gal/min) Capacity(Full Flow)(gal/min) Flow/Capacity(%) Depth(Middle)(ft) Depth/Diameter(%) 3379 P-749 8 PVC 1.77 0.01 MH-1865 MH-1864 3.96 105.2 938.3 11.2 0.22 34 3378 P-755 8 PVC 0.38 0.01 MH-1864 MH-1863 2.31 108.2 436.9 24.8 0.23 34 3377 P-748 8 PVC 1.12 0.01 MH-1863 MH-1862 3.4 109.28 744.6 14.7 0.23 34 3376 P-757 8 PVC 2.04 0.01 MH-1862 MH-1861 4.21 109.56 1,007.1 10.9 0.23 34 3375 P-2421 8 PVC 6.58 0.01 MH-1861 MH-1860 6.39 110.32 1,809.0 6.1 0.27 41 3374 P-739 8 PVC 3.00 0.01 MH-1860 MH-1859 _5._83 210.16 1,221.2 17.2 0.25 38 3373 P-730 8 PVC 2.67 0.01 MH-1859 MH-1858 5.58 210.16 1,151.3 18.3 0.26 38 3372 P-740 8 PVC 8.09 0.01 M_H-1858 MH-658 8.3 210.16 2,005.9 10.5 0.35 52 3353 P-773 8 PVC 1.64 0.01 MH-658 MH-657 5.09 278.86 903.9 30.9 0.37 56 3352 P-772 8 PVC 6.56 0.01 MH-657 MH-841 8.37 279.82 1,806.0 15.5 0.38 56 3356 P-716 8 PVC 0.59 0.01 MH-841 MH-835 ` 3.51 290.82 540.2 53.8 0.36 55 3357 P-715 8 PVC 0.51 0.01 MH-835 MH-828 I 3.34 290.82 505.6 57.5 0.37 56 3359 P-696 8 PVC 0.56 0.01 MH-828 'MH-666 3.46 290.82 528.9 55.0 0.37 55 3369 P-1960 8 PVC 0.56 0.01 MH-666 MH-667 3.46 290.82 529.2 55.0 0.38 57 3368 P-1959 8 PVC 0.52 0.01 MH-667 MH-761 3.38 300.42 508.5 59.1 0.39 59 3346 P-734 8 PVC 0.73 0.01 MH-761 MH-843 3.9 314.3 604.4 52.0 0.40 59 3339 P-778 8 PVC 0.53 0.01 MH-843 MH-743 3.45 315.62 514.9 61.3 0.40 60 3833 P-3190 8 PVC 0.44 0.01 MH-743 MH-3342 3.21 321.22 466.9 68.8 0.40 61 3834 P-3134 8 PVC 1.95 0.01 MH-3342 MH-769 5.62 323.26 984.5 32.9 0.40 60 3338 P-779 8 PVC 5.87 0.01 MH-769 MH-775 8.38 324.06 1,707.8 19.0 0.40 60 3337 P-1560 8 PVC 8.24 0.01 MH-775 MH-656 __9.47 __ 324.98 2,023.6 16.1 0.40 60 3835 P-3135(1) 8 PVC 1.29 0.01 MH-656 MH-663 4.86 326.54 801.6 40.7 0.40 61 3322 P-2266 8 PVC 0.59 0.01 MH-663 MH-671 3.62 328.66 540.4 - 60.8 0.40 61 3321 P-1937 8 PVC 0.49 0.01 MH-6_71 MH-691 3.38 330.54 494.8 66.8 0.41 61 3317 P-1992 8 PVC 0.69 0.01 MH-691 MH-681 3.85 332.82 584.9 56.9 0.41 62 3310 P-2485 8 I PVC 3.31 0.01 MH-681 MH-2124 1 6.99 352.98 1,283.6 27.5 0.42 63 3309 P-1950 8 PVC 5.33 0.01 MH-2124 MH-682 8.29 353.14 1,627.6 21.7 0.42 63 3307 P-1935 8 PVC 5.45 0.01 MH-682 MH-700 8.37 355.1 1,646.3 _ 21.6 0.42 63 3308 P-1952 8 PVC 5.48 0.01 MH-700 MH-693 I 8.39 355.62 1,650.4 21.5 0.42 63 3414 P-661 8 PVC 2.29 0.01 MH-693 MH-684 6.12 355.94 1,066.1 33.4 0.42 63 3431 P-654 8 PVC 1.34 0.01 MH-684 MH-639 5.06 360.78 817.6 44.1 0.43 64 3430 P-623 8 PVC 4.25 0.01 MH-639 MH-738 7.72 365.74 1,454.0 25.2 0.43 64 3831 P-2384 8 PVC 2.32 0.01 MH-738 MH-3341 6.2 366.38 1,073.8 34.1 0.44 65 3832 P-3189 8 PVC 3.38 0.01 M_H-3341 MH-757 7.25 391.86 1,295.6 30.2 0.44 67 3429 P-852 8 PVC 13.93 0.01 MH-757 MH-767 12.11 398.34 2,631.3 15.1 0.45 67 3424 P-2487 8 PVC 7.86 0.01 MH-767 MH-772 9.87 398.78 1,976.3 20.2 0.45 67 3422 P-1941 8 PVC 3.11 0.01 MH-772 MH-777 7.07 399.7 1,242.4 32.2 0.49 74 7144 P-1767 12 PVC 0.22 0.01 MH-777 MH-111,MH-2019 2.84 545.02 975.0 55.9 0.51 51 City of Arlington Lindsay Subarea Sewer Hydraulic Analyses 23-26 On-Call Water & Sewer System Engineering Services Task 3 Results ID Label Diameter(in) Material Slope(Calculated)(%) Manning's n Start Node Stop Node Velocity(ft/s)' Flow(gal/min) Capacity(Full Flow)(gal/min) Flow/Capacity(%) Depth(Middle)(ft) Depth/Diameter(%) 3523 P-1793 8 PVC 0.79 `` 0.01 MH-2243 MH-1820 3.46 181.54 626.1 29.0 0.3 46 3560 P-1880 8 PVC 6.80 I 0.01 MH-1820 MH-1819 7.76 206.18 1,838.8 11.2 0.3 50 3559 P-2593 8 PVC 9.20 ! 0.01 MH-1819 MH-1818 9.04 241.66 2,138.3 11.3 0.3 52 3558 P-857 8 PVC 7.02 0.01 MH-1818 MH-1817 8.21 241.82 1,867.5 12.9 0.3 52 3557 P-856 8 PVC 8.44 0.01 MH-1817 MH-1816 8.79 241.98 2,047.9 11.8 0.3 37 3556 I P-861 10 PVC 5.92 0.01 MH-1816 MH-1815 7.56 242.14 3,111.5 7.8 0.3 39 3555 P-1881 10 PVC 4.57 0.01 MH-1815 MH-1814 6.89 242.3 2,733.0 8.9 0.3 39 3554 I P-1875 10 PVC 4.50 0.01 MH-1814 MH-1813 6.86 242.83 2,710.3 9.0 0.3 39 3553 P-1874 10 PVC 3.28 0.01 MH-1813 MH-1812 6.14 243.36 2,324.8 10.5 0.3 30 3552 P-1877 12 PVC 1.05 0.01 MH-1812 MH-1811 4.01 243.88 2,125.7 11.5 0.3 32 3551 P-860 12 PVC 0.25 0.01 MH-1811 MH-1810 2.41 245.57 1,039.4 23.6 0.3 32 3550 P-859 12 PVC 0.36 0.01 MH-1810 MH-1809 2.76 246.29 1,251.6 19.7 0.3 32 6323 P-1612 12 PVC 0.25 0.01 MH-1809 MH-2552 2.4 249.38 1,029.5 24.2 0.4 36 6324 P-3294 12 PVC 0.22 0.01 MH-2552 MH-1808 2.46 I 310.24 977.7 31.7 0.4 39 3548 P-865 12 PVC 0.23 0.01 MH-1808 MH-1807 2.49 fl 310.77 992.7 31.3 0.4 37 3531 P-3005 12 PVC 1.18 0.01 MH-1807 MH-91 4.49 311.49 2,254.3 13.8 0.4 39 3532 P-3006 12 PVC 0.22 0.01 MH-91 MH-1488 2.6 389.7 969.2 40.2 0.4 44 3547 P-2255 j 12 PVC 17.40 0.01 MH-1488 WW-8 13.21 480.36 8,671.0 5.5 0.7 72 Note:the flow highlighted in Breen is the total flow at LS 8. 8H2 RH2 ENGINEERING Bothell 22722 29th Drive SE,Suite 210 Bothell,WA 98021 1.800.720.8052/rh2.com r�z C April 06, 2026 z$z — O Mr.James X. Kelly, PE Public Works Director City of Arlington 238 N Olympic Avenue C Arlington, WA 98223 Sent via: Email Subject: Hydraulic Analyses for the Proposed Lindsay Subarea Development I Dear Mr. Kelly: This letter presents the results of the hydraulic analyses performed by RH2 Engineering, Inc., (RH2) for the proposed Lindsay Subarea development (development). These analyses were performed using a computer model of the City of Arlington's (City) existing sewer system to determine the flow capacity through the Gleneagle and Lift Station 8 Sewer Basins. �p Background WASHINGTON LOCATIONS The proposed development is located south of 172nd Street NE/State Route 531 Bellingham near 79th Avenue NE, as shown in Attachment 1. At the City's request, hydraulic Bellevue analyses were performed to evaluate the capacity of the existing sewer system to Bothell(Corporate) convey flows from the proposed development through the Gleneagle and Lift East Wenatchee Station 8 basins to Maintenance Hole (MH) 111. MH-111, located at the Richland Tacoma intersection of 67th Avenue NE and Woodland Way, is the most downstream maintenance hole within these basins prior to discharge into the City's primary OREGON interceptor. LOCATIONS Medford Hydraulic Analyses Portland Modeling Scenarios IDAHO Four modeling scenarios were identified to evaluate the sewer system capacity LOCATIONS downstream of the development, as shown below: Nampa I04/06/26 3:08 PM J:\DATA\ARL\23-0018\TO3 LI NDSAY SUBAREA\10 REPORTS\LTR TO 1 KELLY RE LINDSAY SUBAREA DEVELOPMENT.DOCX MR.JAMES X.KELLY, PE RH2 April 6,2026 Page 2 • Scenario 1: Determine the capacity from the stub on 80 Drive NE to the sanitary sewer MH-111 on 67th Avenue NE. • Scenario 2: Determine the capacity of adding 89 lots to Scenario 1. • Scenario 3: Determine the capacity that may be needed for the lots/units west of the 79th Avenue NE subarea using the conservative estimate of 216 concept units. • Scenario 4 (Optional): Determine the potential upgrades necessary to the gravity flow pipe and Lift Station 8 (LS 8) due to adding the east half of the subarea to the west half. Sewer System Loading The developer, MJS Investors, is coordinating with Land Technologies, Inc. to plan and design the development. Land Technologies, Inc. provided the population estimates and corresponding sewer flow assumptions used in the hydraulic analyses presented in this letter. The assumed sewer loading values are summarized in Table 1. Table 1 Sewer Loading Estimates Equivalent Average Daily Peak Hour Residential Flow Peaking Flow Description Units Population (gpd) Ratio (gpm) Scenario 1 139 375 37,530 4.04 105 Scenario 2 89 240 24,030 4.12 69 Scenario 3 216 583 58,320 3.94 160 Scenario 4 228 616 61,560 3.93 168 Hydraulic Analyses Results Peak hour flow (PHF) analyses were conducted using the City's sewer system hydraulic model under the loading conditions shown in Table 1. Per Chapter 5 of the City's 2015 Standards and Specifications, sewer mains shall not exceed 50 percent capacity for new mains and 75 percent capacity for existing mains under PHF conditions, including infiltration and inflow. Detailed modeling results are provided in Attachment 2. The analyses indicate that the existing sewer collection system has adequate capacity to convey existing PHFs plus the proposed development flows identified in Table 1, with no system improvements required. Under Scenario 1, the controlling sewer segment is main P-3190 between MI-Is 743 and 3342, near W Country Club Drive and Muirfield Court, operating at 54.1 percent of capacity. Under Scenario 2, with the addition of 89 lots tributary to the same alignment, this segment remains controlling and operates at 68.8 percent of capacity. Under Scenario 3, the controlling sewer segment is main P-3006 between MHs 91 and 1488, near Highland View Drive and 67th Avenue NE, operating at 40.2 percent of capacity. The 04/06/26 3:08 PM J:\DATA\ARL\23-0018\TO3 LI NDSAY SUBAREA\10 REPORTS\LTR TO 1 KELLY RE LINDSAY SUBAREA DEVELOPMENT.DOCX MR.JAMES X.KELLY, PE RH2 April 6,2026 Page 3 hydraulic analysis was limited to the gravity sewer collection system downstream of the proposed development, with an estimated PHF of approximately 480 gallons per minute conveyed to the downstream system. Analyses for Scenario 4 were not performed because Scenarios 1 through 3 did not identify hydraulic capacity deficiencies requiring further evaluation of gravity sewer improvements. Flow Monitoring To corroborate the modeling results, the City installed flow meters at MI-Is to measure flows in sewer mains P-1525 and P-727 for approximately 11 days. Sewer main P-1525 is located upstream of Lift Station 8 near the intersection of Highland View Drive and 67t"Avenue NE. The modeled PHFs were approximately 69 percent higher than the maximum observed flow. Sewer main P-727 is located upstream of MH-111 near the intersection of Woodlands Way and 67t"Avenue NE. The modeled PHFs were approximately 12 percent higher than the maximum observed flow. Conclusion Based on the results of the hydraulic analyses, no improvements to the existing sewer collection system are required to support development of the Lindsay Subarea. If you have any questions regarding the analyses, please call me at (425) 949-9129 or reach me via email at dbright@rh2.com. Thank you for the opportunity to assist you with this project. Sincerely, D/a'7v wAs Dylan Bright, PE J Project Engineer DB/HSF/DB 24024592 CISTF,, SSIONAL , Attachments: Signed: 04/06/2026 Attachment 1— Lindsay Property Wastewater Connection Routes Attachment 2— Hydraulic Analyses Results 04/06/26 3:08 PM 1:\DATA\ARL\23-0018\TO 3 LI NDSAY SUBAREA\10 REPORTS\LTR TO 1 KELLY RE LINDSAY SUBAREA DEVELOPM ENT.DOCX Attachment 1 , tit IM h a 1 _ _ , l a s Gleneagle 9 - �5 �e ,f - - Oil _ Lindsay �• ahvi - Deuelo � ment , City ofArlington Lindsay Development o@ Sewer Manholes N Lindsay Property Wastewater Wastewater Route 1 Lift Station J Connection Routes Wastewater Route 2 Scale: File: Aerial captured in 2024. 1 inch = 1,000 ft WastewaterLayouts/ This data is provided'as is'without warranty of any kind.The entire risk as to the results and performance of the data is assumed LI n d sayCo n n e ct8x l l 2026 by you.Should the data prove defective,you assume the entire cost of all necessary servicing,repair,or correction.These data and corresponding attributes are not to be used for design purposes.Further,the City of Arlington does not warrant,guarantee,or make any representations regarding the use of,or results from the use of the data in terms of correctness,accuracy,reliability, Date: Cartographer. currentness,or otherwise;and you rely on the data and results solely at your own risk.There are known gaps and inaccuracies in the current data set and the provided information should be considered a draft and in-progress work.Washington State Law,Ch. 4/2/2026 a kc 42.56 RCW,prohibits state and local agencies from providing access to lists of individuals intended for use for commercial 1 tiinY purposes and thus,no commercial use may be made of any Data comprising lists of individuals contained herein. City of Arlington Attachment 2 Lindsay Subarea Sewer Hydraulic Analyses J 23-26 On-Call Water& Sewer System Engineering Services Task 1 Results ID Label Diameter(in) Material Slope(Calculated)(%) Manning's n Start Node Stop Node Velocity NO Flow(gal/min) Capacity(Full Flow)(gal/min) Flow/Capacity(%) Depth(Middle)(ft) Depth/Diameter(%) 3379 P-749 8 PVC 1.77 0.01 MH-1865 MH-1864 3.96 105.2 938.3 11.2 0.22 34 3378 P-755 8 PVC 0.38 0.01 MH-1864 MH-1863 2.31 108.2 436.9 24.8 0.23 34 3377 P-748 8 PVC 1.12 0.01 MH-1863 MH-1862 3.4 109.28 744.6 14.7 0.23 34 3376 P-757 8 PVC 2.04 0.01 MH-1862 MH-1861 4.21 109.56 1,007.1 10.9 0.23 34 3375 P-2421 8 PVC 6.58 0.01 MH-1861 MH-1860 6.39 110.32 1,808.0 6.1 0.27 41 3374 P-739 8 PVC 3.00 0.01 MH-1860 MH-1859 5.83 210.16 1,221.2 17.2 0.25 38 3373 P-730 8 PVC 2.67 0.01 MH-1859 MH-1858 5.58 210.16 1,151.3 18.3 0.26 38 3372 P-740 8 PVC 8.09 0.01 MH-1858 MH-658 8.3 210.16 2,005.9 10.5 0.23 35 3353 P-773 8 PVC 1.64 0.01 MH-658 MH-657 4.69 210.16 903.9 23.3 0.32 48 3352 P-772 8 PVC 6.56 0.01 MH-657 MH-841 7.73 211.12 1,806.0 11.7 0.32 49 3356 P-716 8 PVC 0.59 0.01 MH-841 MH-835 3.28 222.12 540.2 41.1 0.31 47 3357 P-715 8 PVC 0.51 0.01 MH-835 MH-828 3.12 222.12 505.6 43.9 0.32 48 3359 P-696 8 PVC 0.56 0.01 MH-828 MH-666 3.23 222.12 528.9 42.0 0.32 47 3369 P-1960 8 PVC 0.56 0.01 MH-666 MH-667 3.23 222.12 529.2 42.0 0.33 50 3368 P-1959 8 PVC 0.52 0.01 MH-667 MH-761 3.17 231.72 508.5 45.6 0.34 51 3346 P-734 8 PVC 0.73 0.01 MH-761 MH-843 3.66 245.6 604.4 40.6 0.35 52 3339 P-778 8 PVC 0.53 0.01 MH-843 MH-743 3.25 246.92 514.9 48.0 0.35 53 3833 P-3190 8 PVC 0.44 0.01 MH-743 MH-3342 3.04 252.52 466.9 54.1 0.35 53 3834 P-3134 8 PVC 1.95 0.01 MH-3342 MH-769 5.27 254.56 984.5 25.9 0.35 53 3338 P-779 8 PVC 5.87 0.01 MH-769 MH-775 7.83 255.36 1,707.8 15.0 0.35 53 3337 P-1560 8 PVC 8.24 0.01 MH-775 MH-656 8.83 256.28 2,023.6 12.7 0.36 53 3835 P-3135(1) 8 PVC 1.29 0.01 MH-656 MH-663 4.56 257.84 801.6 32.2 0.36 54 3322 P-2266 8 PVC 0.59 0.01 MH-663 MH-671 3.42 259.96 540.4 48.1 0.36 54 3321 P-1937 8 PVC 0.49 0.01 MH-671 MH-691 3.2 261.84 494.8 52.9 0.36 54 3317 P-1992 8 PVC 0.69 0.01 MH-691 MH-681 3.64 264.12 584.9 45.2 0.37 55 3310 P-2485 8 PVC 3.31 0.01 MH-681 MH-2124 6.57 284.28 1,283.6 22.1 0.37 56 3309 P-1950 8 PVC 5.33 0.01 MH-2124 MH-682 7.81 284.44 1,627.6 17.5 0.38 56 3307 P-1935 8 PVC 5.45 0.01 MH-682 MH-700 7.89 286.4 1,646.3 17.4 0.38 56 3308 P-1952 8 PVC 5.48 0.01 MH-700 MH-693 7.91 286.92 1,650.4 17.4 0.28 42 3414 P-661 8 PVC 2.29 0.01 MH-693 MH-684 5.77 287.24 1,066.1 26.9 0.38 57 3431 P-654 8 PVC 1.34 0.01 MH-684 MH-639 4.79 292.08 817.6 35.7 0.38 57 3430 P-623 8 PVC 4.25 0.01 MH-639 MH-738 7.29 297.04 1,454.0 20.4 0.38 58 3831 P-2384 8 PVC 2.32 0.01 MH-738 MH-3341 5.86 297.68 1,073.8 27.7 0.39 59 3832 P-3189 8 PVC 3.38 0.01 MH-3341 MH-757 6.86 323.16 1,295.6 24.9 0.40 60 3429 P-852 8 PVC 13.93 0.01 MH-757 MH-767 11.49 329.64 2,631.3 12.5 0.41 61 3424 P-2487 8 PVC 7.86 0.01 MH-767 MH-772 9.37 330.08 1,976.3 16.7 0.41 61 3422 P-1941 8 PVC 3.11 0.01 MH-772 MH-777 6.7 331 1,242.4 26.6 0.45 67 7144 P-1767 12 PVC 0.22 0.01 MH-777 MH-111,MH-2019 2.75 476.32 975.0 48.9 0.48 48 City of Arlington Attachment 2 Lindsay Subarea Sewer Hydraulic Analyses J 23-26 On-Call Water& Sewer System Engineering Services Task 2 Results ID Label Diameter(in) Material Slope(Calculated)(%) Manning's n Start Node Stop Node Velocity(ft/s) Flow(gal/min) Capacity(Full Flow)(gal/min) Flow/Capacity(%) Depth(Middle)(ft) Depth/Diameter(%) 3379 P-749 8 PVC 1.77 0.01 MH-1865 MH-1864 3.96 105.2 938.3 11.2 0.22 34 3378 P-755 8 PVC 0.38 0.01 MH-1864 MH-1863 2.31 108.2 436.9 24.8 0.23 34 3377 P-748 8 PVC 1.12 0.01 MH-1863 MH-1862 3.4 109.28 744.6 14.7 0.23 34 3376 P-757 8 PVC 2.04 0.01 MH-1862 MH-1861 4.21 109.56 1,007.1 10.9 0.23 34 3375 P-2421 8 PVC 6.58 0.01 MH-1861 MH-1860 6.39 110.32 1,808.0 6.1 0.27 41 3374 P-739 8 PVC 3.00 0.01 MH-1860 MH-1859 5.83 210.16 1,221.2 17.2 0.25 38 3373 P-730 8 PVC 2.67 0.01 MH-1859 MH-1858 5.58 210.16 1,151.3 18.3 0.26 38 3372 P-740 8 PVC 8.09 0.01 MH-1858 MH-658 8.3 210.16 2,005.9 10.5 0.35 52 3353 P-773 8 PVC 1.64 0.01 MH-658 MH-657 5.09 278.86 903.9 30.9 0.37 56 3352 P-772 8 PVC 6.56 0.01 MH-657 MH-841 8.37 279.82 1,806.0 15.5 0.38 56 3356 P-716 8 PVC 0.59 0.01 MH-841 MH-835 3.51 290.82 540.2 53.8 0.36 55 3357 P-715 8 PVC 0.51 0.01 MH-835 MH-828 3.34 290.82 505.6 57.5 0.37 56 3359 P-696 8 PVC 0.56 0.01 MH-828 MH-666 3.46 290.82 528.9 55.0 0.37 55 3369 P-1960 8 PVC 0.56 0.01 MH-666 MH-667 3.46 290.82 529.2 55.0 0.38 57 3368 P-1959 8 PVC 0.52 0.01 MH-667 MH-761 3.38 300.42 508.5 59.1 0.39 59 3346 P-734 8 PVC 0.73 0.01 MH-761 MH-843 3.9 314.3 604.4 52.0 0.40 59 3339 P-778 8 PVC 0.53 0.01 MH-843 MH-743 3.45 315.62 514.9 61.3 0.40 60 3833 P-3190 8 PVC 0.44 0.01 MH-743 MH-3342 3.21 321.22 466.9 68.8 0.40 61 3834 P-3134 8 PVC 1.95 0.01 MH-3342 MH-769 5.62 323.26 984.5 32.8 0.40 60 3338 P-779 8 PVC 5.87 0.01 MH-769 MH-775 8.38 324.06 1,707.8 19.0 0.40 60 3337 P-1560 8 PVC 8.24 0.01 MH-775 MH-656 9.47 324.98 2,023.6 16.1 0.40 60 3835 P-3135(1) 8 PVC 1.29 0.01 MH-656 MH-663 4.86 326.54 801.6 40.7 0.40 61 3322 P-2266 8 PVC 0.59 0.01 MH-663 MH-671 3.62 328.66 540.4 60.8 0.40 61 3321 P-1937 8 PVC 0.49 0.01 MH-671 MH-691 3.38 330.54 494.8 66.8 0.41 61 3317 P-1992 8 PVC 0.69 0.01 MH-691 MH-681 3.85 332.82 584.9 56.9 0.41 62 3310 P-2485 8 PVC 3.31 0.01 MH-681 MH-2124 6.99 352.98 1,283.6 27.5 0.42 63 3309 P-1950 8 PVC 5.33 0.01 MH-2124 MH-682 8.29 353.14 1,627.6 21.7 0.42 63 3307 P-1935 8 PVC 5.45 0.01 MH-682 MH-700 8.37 355.1 1,646.3 21.6 0.42 63 3308 P-1952 8 PVC 5.48 0.01 MH-700 MH-693 8.39 355.62 1,650.4 21.5 0.42 63 3414 P-661 8 PVC 2.29 0.01 MH-693 MH-684 6.12 355.94 1,066.1 33.4 0.42 63 3431 P-654 8 PVC 1.34 0.01 MH-684 MH-639 5.06 360.78 817.6 44.1 0.43 64 3430 P-623 8 PVC 4.25 0.01 MH-639 MH-738 7.72 365.74 1,454.0 25.2 0.43 64 3831 P-2384 8 PVC 2.32 0.01 MH-738 MH-3341 6.2 366.38 1,073.8 34.1 0.44 65 3832 P-3189 8 PVC 3.38 0.01 MH-3341 MH-757 7.25 391.86 1,295.6 30.2 0.44 67 3429 P-852 8 PVC 13.93 0.01 MH-757 MH-767 12.11 398.34 2,631.3 15.1 0.45 67 3424 P-2487 8 PVC 7.86 0.01 MH-767 MH-772 9.87 398.78 1,976.3 20.2 0.45 67 3422 P-1941 8 PVC 3.11 0.01 MH-772 MH-777 7.07 399.7 1,242.4 32.2 0.49 74 7144 P-1767 12 PVC 0.22 0.01 MH-777 MH-111,MH-2019 2.84 545.02 975.0 55.9 0.51 51 City of Arlington Attachment 2 Lindsay Subarea Sewer Hydraulic Analyses J 23-26 On-Call Water& Sewer System Engineering Services Task 3 Results ID Label Diameter(in) Material Slope(Calculated)(%) Manning's n Start Node Stop Node Velocity(ft/s) Flow(gal/min) Capacity(Full Flow)(gal/min) Flow/Capacity(%) Depth(Middle)(ft) Depth/Diameter(%) 3523 P-1793 8 PVC 0.79 0.01 MH-2243 MH-1820 3.46 181.54 626.1 29.0 0.3 46 3560 P-1880 8 PVC 6.80 0.01 MH-1820 MH-1819 7.76 206.18 1,838.8 11.2 0.3 50 3559 P-2593 8 PVC 9.20 0.01 MH-1819 MH-1818 9.04 241.66 2,138.3 11.3 0.3 52 3558 P-857 8 PVC 7.02 0.01 MH-1818 MH-1817 8.21 241.82 1,867.5 12.9 0.3 52 3557 P-856 8 PVC 8.44 0.01 MH-1817 MH-1816 8.79 241.98 2,047.9 11.8 0.3 37 3556 P-861 10 PVC 5.92 0.01 MH-1816 MH-1815 7.56 242.14 3,111.5 7.8 0.3 39 3555 P-1881 10 PVC 4.57 0.01 MH-1815 MH-1814 6.89 242.3 2,733.0 8.9 0.3 39 3554 P-1875 10 PVC 4.50 0.01 MH-1814 MH-1813 6.86 242.83 2,710.3 9.0 0.3 39 3553 P-1874 10 PVC 3.28 0.01 MH-1813 MH-1812 6.14 243.36 2,314.8 10.5 0.3 30 3552 P-1877 12 PVC 1.05 0.01 MH-1812 MH-1811 4.01 243.88 2,125.7 11.5 0.3 32 3551 P-860 12 PVC 0.25 0.01 MH-1811 MH-1810 2.41 245.57 1,039.4 23.6 0.3 32 3550 P-859 12 PVC 0.36 0.01 MH-1810 MH-1809 2.76 246.29 1,251.6 19.7 0.3 32 6323 P-1612 12 PVC 0.25 0.01 MH-1809 MH-2552 2.4 249.38 1,029.5 24.2 0.4 36 6324 P-3294 12 PVC 0.22 0.01 MH-2552 MH-1808 2.46 310.24 977.7 31.7 0.4 39 3548 P-865 12 PVC 0.23 0.01 MH-1808 MH-1807 2.49 310.77 992.7 31.3 0.4 37 3531 P-3005 12 PVC 1.18 0.01 MH-1807 MH-91 4.49 311.49 2,254.3 13.8 0.4 39 3532 P-3006 12 PVC 0.22 0.01 MH-91 MH-1488 2.6 389.7 969.2 40.2 0.4 44 3547 P-2255 12 PVC 17.40 0.01 1 MH-1488 WW-8 1 13.21 1 480.36 1 8,671.0 1 5.5 1 0.7 1 72 Note:the flow highlighted in green is the total flow at LS 8.