CHAPTER V - EXISTING FACILITIES - Alderwood Water · CHAPTER V - EXISTING ... 116644TThh sSStt SWW 1132N dd St E ... c V i e w D r O l y p i V i D 5 8 T h 3 A v W 8 28Th St 9 T h

COMPREHENSIVE SEWER PLAN

CHAPTER V - EXISTING FACILITIES 5.1 DRAINAGE BASINS The District’s service area is divided into five separate drainage basins as presented on Figure 5.1. These five basins include the following with a more detailed description of each basin in Section 5.2:

• North Creek Drainage Basin. The North Creek flows in a southerly direction and is defined as the area tributary to King County’s North Creek Interceptor. Flow in this trunk flows to the King County system and is currently treated at the West Point WWTP. Ultimately, when the Brightwater plant is completed, these flows will be treated at the Brightwater facilities.

• Swamp Creek Drainage Basin. Swamp Creek basin is one of three south

flowing basins in the District’s service area. Swamp Creek basin can be defined as flow that is collected and conveyed by King County’s Swamp Creek Interceptor. Flow in this trunk flows to the King County system and is currently treated at the West Point WWTP. Ultimate treatment and disposal will be at the Brightwater WWTP when that facility is commissioned.

• South Everett Drainage Basin. Flow from this basin is located in the northern

segment of the service area. Flows are conveyed either through gravity system or are pumped from the District’s Lift Stations No. 21 and No. 11 in a northerly direction to the City of Everett collection system. Flow is conveyed to the City’s WWTP which then discharges to Puget Sound.

• Picnic Point Drainage Basin. This basin is located in the northwest corner of

the District and all wastewater from this basin is collected and transported to the District’s Picnic Point Wastewater Treatment Plant.

• Little Bear Creek Drainage Basin. Located along the eastern boundary of the

service area, the Little Bear Creek Basin flows in a southerly direction and ties into King County’s Little Bear Creek Interceptor.

5.1.1 North Creek Drainage Basin The North Creek Drainage Basin consists of 12,202 acres. Approximately 82% of the 2006 population receives sewer service. This basin includes portions of the Snohomish UGA, and the Cities of Mill Creek and Bothell. The North Creek Basin land use within each of these three entities is presented in Table 5.1. Forty-one mini-basins exist within the North Creek Basin. These mini-basin boundaries are presented schematically in Figure 5.2. This drainage basin also includes two lift stations:

5-1

BHC Consultants, LLC720 Third Avenue, Suite 1200Seattle, Washington 98104-1820206.505.3400206.505.3406 (fax)www.bhcconsultants.com

NC-18 (Fig J.19)

SC-8 (Fig J.50)

PP-2 (Fig J.69)

NC-22 (Fig J.23)

EV-1 (Fig J.67)

SC-14 (Fig J.56)

NC-3 (Fig J.4)

NC-34 (Fig J.35)

PP-12 (Fig J.79)

SC-1 (Fig J.43)

PP-9 (Fig J.76)

SC-2 (Fig J.44)

NC-36 (Fig J.37)

NC-23 (Fig J.24)

SC-12 (Fig J.54)

SC-18 (Fig J.60)

NC-2 (Fig J.3)

NC-33 (Fig J.34)

Nc-24 (Fig J.25)

SC-21 (Fig J.63)

NC-29 (Fig J.30)

NC-1 (Fig J.2)

NC-19 (Fig J.20)

PP-8 (Fig J.75)

SC-16 (Fig J.58)

NC-15 (Fig J.16)SC-11

(Fig J.53)

PP-6 (Fig J.73)

NC-8 (Fig J.9)

SC-17 (Fig J.59)

NC-30 (Fig J.31)

SC-6 (Fig J.48)

NC-41 (Fig J.42)NC-39

(Fig J.40)

NC-27 (Fig J.28)NC-26

(Fig J.27)

NC-20 (Fig J.21)

NC-35 (Fig J.36)

NC-31 (Fig J.32)

SC-19 (Fig J.61)

NC-40 (Fig J.41)

SC-22 (Fig J.64)

PP-13 (Fig J.80)

PP-5 (Fig J.72)

SC-10 (Fig J.52)

NC-12 (Fig J.13)

NC-17 (Fig J.18)

SC-23 (Fig J.65)

PP-3 (Fig J.70)

NC-32 (Fig J.33)

NC-13 (Fig J.14)

NC-5 (Fig J.6)

NC-10 (Fig J.11)

NC-4 (Fig J.5)

NC-21 (Fig J.22)

NC-38 (Fig J.39)SC-24

(Fig J.66)

SC-5 (Fig J.47)

NC-16 (Fig J.17)

NC-9 (Fig J.10)SC-9

(Fig J.51)NC-14

(Fig J.15)

SC-3 (Fig J.45)

PP-4 (Fig J.71)

PP-10 (Fig J.77)

SC-13 (Fig J.55)

SC-15 (Fig J.57)

NC-25 (Fig J.26)

NC-37 (Fig J. 38)

SC-4 (Fig J.46)

PP-1 (Fig J.68)

BC-1 (Fig J.81)

PP-7 (Fig J.74)

NC-11 (Fig J.12)SC-7

(Fig J.49)PP-11 (Fig. J.78)

SC-20 (Fig J.62)

NC-7 (Fig J.8)

NC-28 (Fig J.29)

NC-6 (Fig J.7)

SR 9

SESR

9 SE

SR 99

SR 99

SR 52

2SR

522

35Th

Ave S

E35

Th Av

e SE

Hwy 9

9Hw

y 99

76Th

Ave W

76Th

Ave W

180Th St SE180Th St SE

Maltby RoadMaltby Road

SR 52

5SR

525

Broa

dway

Ave

Broa

dway

Ave

Ash W

ayAs

h Way


196Th St SW196Th St SW


132Nd St SE132Nd St SE



Filbert RoadFilbert Road

SR 527 HwySR 527 Hwy


Locust Way

Locust Way

Mano

r Way

Mano

r Way

Seatt

le Hil

l Roa

d

Seatt

le Hil

l Roa

d

Poplar WayPoplar Way

ElliottElliott

48Th

Ave W

48Th

Ave W

36Th

Ave W

36Th

Ave W

Beverly Park R

oad

Beverly Park R

oad

Larch

Way

Larch

Way

SR 52

7 SE

SR 52

7 SE


North

Roa

dNo

rth R

oad

4Th A

ve W

4Th A

ve W

66Th

Ave W

66Th

Ave W

84Th

Ave W

84Th

Ave W

88Th

Ave W

88Th

Ave W

52Nd

Ave W

52Nd

Ave W

Main StMain St

Mukilteo Spdwy

Mukilteo Spdwy

Edmonds Way

Edmonds Way

44Th

Ave W

44Th

Ave W

56Th

Ave W

56Th

Ave W

236Th236Th


19Th

Ave S

E19

Th Av

e SE

39Th

Ave S

E39

Th Av

e SE





Airport RoadAirport Road

10Th

Dr S

E10

Th D

r SE


9Th A

ve S

E9T

h Ave

SE

S 2Nd Ave

S 2Nd Ave

64Th

Ave W

64Th

Ave W

Picnic Point RoadPicnic Point Road

Walnut StWalnut St




60Th

Ave W

60Th

Ave W

226T

h St S

W22

6Th S

t SW

Paradise Lake Road

Paradise Lake Road

5Th A

ve S

5Th A

ve S

30Th

Ave W

30Th

Ave W

Olym

pic Av

eOl

ympic

Ave

Olym

pic V

iew D

rOl

ympic

View

Dr

58Th

Ave W

58Th

Ave W


9Th A

ve N

9Th A

ve N


Mill Creek RoadMill Creek Road

14Th Ave W14Th Ave W

Ponti

us R

oad

Ponti

us R

oad

9Th A

ve S

9Th A

ve S

Casc

adian

Way

Casc

adian

Way

75Th

Pl W

75Th

Pl W

E Lowell Larimer RoadE Lowell Larimer Road


3Rd A

ve N

3Rd A

ve N


146T

h St S

E14

6Th S

t SE

Shelby RoadShelby Road

68Th

Ave W

68Th

Ave W

NE 205Th StNE 205Th St

Madison WayMadison Way

Brier

Road

Brier

Road

3Rd A

ve S

3Rd A

ve S

Cedar WayCedar Way


Puget Dr

Puget Dr

95Th

Pl W

95Th

Pl W

28Th

Ave W

28Th

Ave W

100T

h Ave

W10

0Th A

ve W


37Th Ave W37Th Ave W

73Rd Pl W73Rd Pl W

100T

h St S

E10

0Th S

t SE

Snoh

omish

Cas

cade

Dr

Snoh

omish

Cas

cade

Dr


Alderwood Mall Blvd

Alderwood Mall Blvd

172Nd St SW172Nd St SW

Dumas RoadDumas Road

Cedar Way S

Cedar Way S

SR 104SR 104

3Rd A

ve S

E3R

d Ave

SE

134Th Pl SE

134Th Pl SE

W Cypress W

ayW

Cypress Way

34Th

Ave W

34Th

Ave W

50Th

Ave W

50Th

Ave W

SR 99

SR 99

Larch WayLarch Way


19Th

Ave S

E

19Th

Ave S

E

19Th

Ave S

E19

Th Av

e SE

228Th St SW228Th St SW228Th St SW228Th St SW

Main StMain St

220T

h St S

W22

0Th S

t SW

28Th

Ave W

28Th

Ave W

44Th

Ave W

44Th

Ave W

52Nd

Ave W

52Nd

Ave W



52Nd

Ave W

52Nd

Ave W

Alderwood Mall Blvd

Alderwood Mall Blvd

N 205th StN 205th St

8th Av

e NW

8th Av

e NW

Ceda

r Way

SCe

dar W

ay S

19th

Ave N

E19

th Av

e NE

5.1

NORT

H

Mini-Basin and DrainageBasin MapAlderwood Water & Wastewater DistrictSnohomish County, Washington

Figure

P:\M

appin

g\Map

s_Ge

nera

ted\A

WW

D\99

-402

98.01

\003\m

aps\5

.1_Mi

niBas

in&Dr

ainag

eBas

in_11

x17.m

xd

§̈¦5

§̈¦5

Scale in Feet

0 5000 10000

§̈¦504

LegendAWWD District Sewer BoundaryUrban Growth AreaBasin BoundaryInterstate HighwaysMajor Roads

NC-1(Fig J.2)

Mini-Basin(Referenced Figure in Appendix J)

Basin High Density Low Density Low Density Open Space and TotalCommercial Mixed Use Multi-Family Multi-family Single Family Miscellaneous Area

Industrial (acres) (acres) (acres) (acres) (acres) Areas (acres) (acres)North Creek

Snohomish UGA 813 26 260 704 4,658 439 6,900Mill Creek 329 141 99 1,171 118 1,858Bothell 672 171 102 2,279 219 3,443Mukilteo 0Lynnwood 0Everett 0North Creek Subtotal 1,814 338 461 704 8,108 776 12,201

Snohomish UGA 1,438 34 1,062 1,357 3,014 140 7,045Mill Creek 0Bothell 6 313 6 325Mukilteo 0Lynnwood 110 8 159 6 283Everett 16 16Swamp Creek Subtotal 1,548 58 1,068 1,357 3,486 152 7,669

Picnic PointSnohomish UGA 423 289 736 1,382 123 2,953Mill Creek 0Bothell 0Mukilteo 336 72 111 367 38 924Lynnwood 0Everett 0Picnic Point Subtotal 759 72 400 736 1,749 161 3,877

EverettSnohomish UGA 354 188 86 1 629Mill Creek 0Bothell 0Mukilteo 0Lynnwood 0Everett 0Everett Subtotal 354 0 188 86 1 0 629

Little Bear CreekSnohomish UGA 121 121Mill Creek 0Bothell 0Mukilteo 0Lynnwood 0Everett 0Bear Creek Subtotal 121 0 0 0 0 0 121

TOTAL AREA 4,596 468 2,117 2,883 13,344 1,089 24,497

Swamp Creek

Table 5.1 Land Use by Basin and Agency

NC-1 / ALDN08 11

NC-3 / SLWD TRIB

NC-2 / ALDN09

NC-9 / ALD6ANC-10 / ALD022

NC-13 / ALD021

NC-11 / ALD024

NC-4 / SLV001

NC-15 / ALD6C

NC-18 / ALD006B

NC-26 / ALD041

NC-23 / ALD031

NC-29 / ALD001ANC-28 / ALDN04

NC-35 / ALD013

QUEENSBOROUGH

TRUNK

10" TO 15"

NC-37 / ALD002

NC-36 / ALD035

NC-38 / ALDN05

NC-39 / ALD034

NC-40 / NCREK012

NC-32 / ALD012

NC-41 / ALDN07

NC-34 / ALDN06

NC-33 / ALD030

NC-31 / ALDN30NC-30 / ALD040

NC-12 / ALD026

NC-14 / ALD019

NC-5 / SLV004 NC-7 / SLV003

NC-6 / SLV002

NC-25 / ALDN013

NC-27 / ALD011

OLYMPUS

MEADOWS TRUNK

15" TO 18"

NC-22 / ALD038

NC-21 / ALD037

NC-20 / ALD033

NC-17 / ALD025NC-19 / ALD023N

NC-16 / ALD009

NC-24 / ALD028

PENNY CREEK

TRUNK

15" TO 18"

NORTH CREEK

TRUNK

21" TO 42"

6" FM

10" - 18"

EXISTING CAPACITY: 300 GPM / ___ GPM

FUTURE CAPACITY: 600 GPM / ___ GPM

*

WATER & WASTEWATER

DISTRICT5.2

North Creek Basin

Mini-basin Flow Schematic

Alderwood Water & Wastewater District

Snohomish County, Washington

6" FM

17

18

NC-1 / ALDN008

(NEW NAME / KC NAME)* LIFT STATION NO. 11 IS SLATED TO BE DIRECTED TO NORTH CREEK IN 2008


• Lift Station No. 11 - This lift station currently pumps to the City of Everett’s system. However, at the time of this report, Lift Station No. 11 was in the midst of the design process to redirect the flow to the North Creek system.

• Lift Station No. 17 - Collects flow from Martha Lake Park and the residential areas east of Interstate 5 and north of Martha Lake. This station is slated to be redirected to the Swamp Creek Basin and has been included in the CIP in Chapter 8.

The North Creek drainage basin is bordered by Swamp Creek on the west. The eastern boundary is established by the eastern District boundary and ridgeline that separates North and Little Bear Creeks. The southern boundary is the Snohomish-King County line. The north border is defined by the inter-agency service agreement with the Silver Lake Water and Sewer District.

There are four major trunk lines within the North Creek Basin. These trunks include the King County North Creek Interceptor and the District’s Queensborough Interceptor, the Olympus Meadows Trunk and the Penny Creek Trunk. Table 5.2 provides a summary of these trunks and their characteristics.

Table 5.2

North Creek Sewer Trunks

Name Discharge Location

Range of Pipe Diameters (inches) Total Length (feet)

North Creek Interceptor

KCDNR – 42-inch Sewer Line

21 to 42 34,934

Queensborough Interceptor

North Creek Trunk – 214th St. SE, west of

SR 527

10 to 15 12,274

Penny Creek Trunk North Creek Trunk -164th St. SE and Mill

Creek Blvd

15 to 18 12,395

Olympus Meadows Trunk

North Creek Trunk 15 to 18 17,686

The King County North Creek Interceptor begins at 164th St SE and continues south to the county line where it meets with the King County North Creek Trunk. The North Creek Trunk provides gravity conveyance to the North Creek Drainage Basin including the Silver Lake Tributary Area. The trunk ultimately serves all customers within the North Creek Basin. The District’s continuation of the North Creek Trunk begins at 164th ST SE and extends in a general northerly direction to serve the north central portion of the North Creek Basin.

The Queensborough Interceptor conveys flows from an area in the south east potion of the North Creek Drainage Basin, west of Interstate 405. The Queensborough area served by this pipeline includes a portion of Alderwood conveyance lines that are

5-5


located within the City of Bothell. The 15-inch to 18-inch diameter trunk begins at the intersection of 29th Dr. SE and 168th St. SE. The trunk terminates on 214th St. SE at a 21-inch segment of the North Creek Interceptor.

The northeast corner of the Alderwood sewer service area is served by the Penny Creek Trunk. This trunk collects flow from the Silver Lake Water and Sewer District and portions of the City of Mill Creek. The trunk begins just south of the Alderwood service boundary adjacent to Penny Creek. Following the creek to the southwest, the trunk discharges to the North Creek Interceptor at 164th St. SE and Mill Creek Blvd. The Olympus Meadows Trunk is currently being upgraded by the District as part of the North Creek Interceptor/Olympus Meadows Trunk sewer improvements project. The Olympus Meadows Trunk generally flows from north to south and currently joins the County’s North Creek Interceptor at approximately 203rd St. SE. The Olympus Meadows Trunk generally serves the central eastern segment of the North Creek Basin. 5.1.2 Swamp Creek Drainage Basin This drainage basin consists of 7669 acres. Approximately 76 percent of the 2006 population receives sewer service. This basin includes portions of the Snohomish UGA, and the Cities of Lynnwood, Everett and Bothell. The Swamp Creek Basin land use within each of these four entities is presented in Table 5.1. This drainage basin has been divided into 24 mini-basins. These mini-basin delineations are presented graphically on Figure 5.3.

This drainage basin includes four lift stations.

• Lift Station No. 2 – Serves a small commercial and residential area at the

intersection of Highway 99 and the Mukilteo Speedway. • Lift Station No. 3 – Currently in standby mode, but can be put back into service if

flows need to be diverted to Picnic Point Drainage Basin. This station is scheduled to be decommissioned in 2008.

• Lift Station No. 7 – Provides service to commercial and residential connections

located between the Mukilteo Speedway and Highway 99.

• Lift Station No. 17 – This station currently pumps to the North Creek system but it is scheduled to be redirected in 2008.

• Lift Station No. 19 – Collects flows from the Brierwood Meadows residential area.

There are four major trunk lines within the Swamp Creek Drainage Basin. These trunks include the King County’s Swamp Creek Trunk and the District’s Martha Lake Trunk, the Larch Way Trunk, and the Meridian Sewer Trunk. Table 5.3 provides a summary of these trunks and their characteristics.

5-6

SC-18 / ALD006

SC-6 / ALDN12SC-9 / ALD020 SWAMP CREEK

TRUNK

12" TO 36"

EXISTING CAPACITY: 100 GPM

FUTURE CAPACITY: 150 GPM

6" FM

EXISTING CAPACITY: 300 GPM / 330 GPM

FUTURE CAPACITY: 300 GPM / 330 GPM

SC-7 / ALD003

SC-5 / ALDN11

SC-3 / ALD014A36" FM

2 SC-4 / ALD14B

7 SC-1 / ALD018

SC-8 / ALD12

SC-11 / ALD12ASC-10 / ALDN01

SC-15 / ALD12B

SC-19 / ALD007A

SC-21 / ALD008

SC-17 / ALD004

SC-16 / ALD005

SC-20 / ALDN02

SC-22 / ALDN00MERIDIAN TRUNK

12"

SC-24 / ALDN03

SC-23 / ALD010A

19

FUTURE

4" FM LARCH WAY

TRUNK

12" TO 36"


4" FM

SC-14 / ALD 039A

SC-13 / ALD016A

SC-12 / ALD015

MARTHA

LAKE TRUNK

12" TO 18"

FUTURE

FMFUTURE CAPACITY: 200 GPM / 250 GPM



STANDBY FORCE MAIN

8" FM

TO PICNIC

POINT WWTP

** FLOWS FROM NC-8 ARE SLATED TO BE

REDIRECTED TO SWAMP CREEK

*** LIFT STATION NO. 3 WILL BE

DECOMMISSIONED IN 2009. STANDBY

FORCEMAIN WILL BE ABANDONED.

* * *

6" FM17 NC-8/ALD032

* *EXISTING CAPACITY: 200 GPM / 300 GPM


WATER & WASTEWATER

DISTRICT

Swamp Creek Basin




5.3

6" FM

17

18

NC-1 / ALDN008

(NEW NAME / KC NAME)


Table 5.3 Swamp Creek Sewer Trunks



King County Swamp Creek Trunk

KCDNR – NE Lake Washington Sewer

Trunk

12 to 36 39,884

Martha Lake Trunk King County Swamp Creek Trunk –

Interstate 405 & Filbert Road Intersection

12 to 18 8,223

Larch Way Trunk King County Swamp Creek Trunk – Locust Way & Cypress Way Intersection

12 to 36 14,990

Meridian Sewer Trunk

KCDNR – Northshore Utility

District Sewer Main

12 9,318

The King County Swamp Creek Trunk for the most part follows the drainage route of Swamp Creek, which originates north of the Alderwood Service Area and flows south across the Snohomish/ King County line to the Sammamish River. The upstream end of the trunk is located on Manor Way just north of 148th St. SW and east of the intersection of Highway 99 and State Route 525. The trunk continues south until it crosses the county line. This trunk ultimately conveys all flows generated in the Swamp Creek basin with the exception of those that utilize the Meridian Trunk.

The Martha Lake Trunk begins just south Martha Lake and continues south until it intersects with the King County Swamp Creek Trunk at the intersection of Locust Way & Cypress Way. This trunk serves residential areas on the southern and eastern shores of Martha Lake as well as an area south of the Lake.

The Larch Way Trunk serves an area north of the City of Brier and an area east of Interstate-5 referred to as Alderdale. The trunk also collects flows from Lift Station No. 19. The Larch Way Trunk flows southwest until it intersects with the King County Swamp Creek Trunk where the Scriber Creek flows into Swamp Creek at the intersection of Locust Way and Cypress Way.

The Meridian Trunk begins at the intersection of 4th Ave W and 224th St. SW and connects to King County’s Swamp Creek Trunk at the County Line. The trunk collects flows from the south west portion of the Queensborough area, which includes customers located within the Bothell city limits.

5-8


5.1.3 South Everett Drainage Basin This drainage basin consists of 629 acres (mini-basin EV-1). Approximately 91 percent of the 2006 population receives sewer service. This basin includes portions of the Snohomish UGA. The South Everett Basin land use within this entity is presented in Table 5.1. The service area includes residential and commercial customers located primarily between Interstate 5 and Highway 99. Lift Station No. 21, which collects flow from mini-basin SC-2 and currently pumps to Everett, is slated to be removed from service as the Swamp Creek interceptor is extended. Consequently, further flows from this mini-basin will be re-routed from the Everett system to the Swamp Creek drainage basin. Mini-basin NC-1 is served by Lift Station No. 11. Currently this station pumps to Everett, but will be redirected to the North Creek System in 2008. Gravity flow from mini-basin EV-1 flows in a northeasterly direction to the Everett system for treatment and disposal. This basin is shown schematically in Figure 5.4. It is anticipated that this mini-basin will continue to flow to Everett by gravity. 5.1.4 Picnic Point Drainage Basin

This drainage basin is the source of all flow that is ultimately received by the District-owned Picnic Point WWTP. This basin includes portions of the Snohomish UGA, and the City of Mukilteo. The Picnic Point Basin land use within each of these two entities is presented in Table 5.1.The treatment plant is currently in the midst of an upgrade which consists of a conversion from a 3 MGD conventional treatment facility to a 6 MGD membrane bioreactor (MBR) plant.

The basin includes 3,877 acres, much of which is characterized by steep slopes along the western boundaries. Sewer service in the basin is provided by means of six lift stations.

• Lift Station No. 4 – Provides service to the west side of Lake Serene (see

Appendix J, Figure J.77). • Lift Station No. 5 – The service area is between 52nd Ave W and Highway 99

between 165th Pl. SW and 143rd Pl. SW (see Appendix J, Figure J.79). • Lift Station No. 6 – Serves residential areas between 14 St. SW and 152nd St.

SW, west of 52nd Ave (see Appendix J, Figure J.75). • Lift Station No. 16 – Serves the Soundview Hills residential development (see

Appendix J, Figure J.75).

5-9

EV-1 / ALDN10

TO EVERETT

8" FM

21 SC-2 / ALD018AEXISTING CAPACITY: 500 GPM

FUTURE CAPACITY: 1,450 GPM

6" FM

17

18

NC-1 / ALDN008


Everett Basin




5.4WATER & WASTEWATER

DISTRICT


• Lift Station No. 18 – Provides service to the residences north and south of Picnic Point Road in the vicinity of the treatment plant (see Appendix J, Figure J.72).

• Lift Station No. 20 – Collects flows from residential areas in the northwest corner

of the Alderwood service area (see Appendix J, Figure J.69).

The Harbor Point Trunk and the Picnic Point Trunk are the two main trunk lines that ultimately convey all the flows generated within the Picnic Point Drainage basin. Together, these trunk lines total over 30,000 feet and range in pipe diameters from 8 to 24 inches. Flows from these trunks are conveyed to the Picnic Point WWTP. Table 5.4 provides a detailed summary of the trunk characteristics.

Table 5.4

Picnic Point Sewer Trunks



Harbor Point Trunk Picnic Point WWTP 8 to 24 17,998 Picnic Point Trunk Picnic Point WWTP 12 to 24 13,310

The Harbor Point Trunk collects flows from the northwest corner of the drainage basin. The service area includes industrial (e.g., the Boeing Manufacturing Facilities), commercial and residential customers. Some of these customers are located within the Mukilteo City limits. Flows from Lift Station No. 20 are conveyed using the Harbor Point Trunk.

The Picnic Point Trunk collects sewage from the remaining portion of the drainage basin. The service area is primarily residential and includes flows from Lift Stations 5, 6, 16, and 18, as well as the West Lake Serene Area via Lift Station No. 4.

The Picnic Point Drainage Basin has been further divided into subdrainage basins known as mini-basins. These mini-basins are illustrated schematically in Figure 5.5. There are 13 mini-basins within the Picnic Point Drainage Basin. 5.1.5 Little Bear Creek Drainage Basin

The Little Bear Creek basin is generally outside the service area of the District. However, a small portion of this basin is within the District boundaries and the Snohomish UGA limits. All of this included area carries a commercial/industrial land use designation (see Table 5.1). 5.2 MINI-BASIN DELINEATION King County investigated and conducted a Regional Infiltration and Inflow (I/I) Control Program in conjunction with local agencies, including AWWD. As part of this program smaller flow basins within the larger drainage basins, or mini-basins, were established. Within the Alderwood service boundary, King County delineated 45 such mini-basins.

5-11

NORTHWEST

LIFT STATION

EXISTING CAPACITY: NA / NA GPM

FUTURE CAPACITY: 200 GPM / 250 GPMPP-1 / ALDN15

20

6" FM



PICNIC POINT

WWTP18

6" FM

PICNIC POINT

LIFT STATION


FUTURE CAPACITY: 210 GPM / 260 GPMPP-4 / PICNIC

PP-6 / ALDN17



6EXISTING CAPACITY: 500 GPM / 550 GPM

FUTURE CAPACITY: 1,050 GPM / 1,150 GPMPP-8 / ALDN14

10" FM

16EXISTING CAPACITY: 125 GPM / 150 GPM


LIFT STATION

AT SUNSET

BAY MARINA


FUTURE CAPACITY: 100 GPM / 125 GPMPP-7 / MARINA



PP-3 / ALDN19 PP-9 / ALDN13

PICNIC POINT

TRUNK

12" TO 24"

4" FM4


FUTURE CAPACITY: 200 GPM / 250 GPMPP-10 / ALD0N14C

5EXISTING CAPACITY: 1,500 GPM / 1,750 GPM

FUTURE CAPACITY: 2,500 GPM / 3,000 GPMPP-12 / ALDN20 PP-13 / ALDN22

14" FM

HARBOR POINT

TRUNK

8" TO 24"

FUTURE 6" FM

FUTURE FM

4" FM

FUTURE FM's

FUTURE

LIFT STATION

WATER & WASTEWATER

DISTRICT5.5

Picnic Point Basin




6" FM

17

NC-1 / ALDN008


FUTURE

LIFT STATION


This refinement was based on a parcel by parcel examination that focused on the specific contour lines and the gradation of the land. During this analysis, most of the mini-basins boundaries were redefined. New mini-basins were added while other were split. Though the King County naming convention was found to be somewhat cumbersome and slightly confusing, it was felt that retaining the original King County mini-basin naming was important if future coordination with the King County effort was necessary. Consequently, this Plan has carried both the original King County mini-basin names as well as the new min-basin names as selected by the District. The naming convention used for any new mini-basins was kept similar to the King County naming convention for consistency. After the reapportionment was complete, the total number of mini-basins within the Alderwood service boundary was revised to include 80 mini-basins. A list of mini-basins is shown in Table 5.5 by major basin. Individual figures for each of the 80 mini-basins are introduced in Chapter 8 and presented in Appendix J. These figures reflect the mini-basin boundaries, identification of the existing sewer facilities, graphical depiction of the chronic maintenance problems, future line extensions to each parcel and CIP projects resulting from the modeling effort. 5.3 CONNECTIONS WITH OTHER SEWERING AGENCIES Alderwood has connections with several adjacent sewer service providers. These connections include agreements with: KCDNR, City of Brier, City of Everett, Silver Lake Water and Sewer District, Northshore Utility District, Mukilteo Water District, and the City of Bothell. The terms and conditions of these connections are defined in Alderwood’s sewer service agreements. A discussion of these agreements is found in Chapter 3. 5.4 LIFT STATIONS Alderwood has a total of 12 active lift stations and one lift station in an idle standby mode. The vast majority of the District lift stations and their emergency generators are manufactured by Smith & Loveless. Per the August 2002, Developer Guidelines and Standards For Developer Extensions, future lift stations installed in the District are required to be Smith & Loveless, above ground, standard wet well mounted pump stations. These stations have two pumps and bubbler level sensors for pump control. The pump controls are located at the stations themselves. However, the District is currently updating its lift station standards and will require future stations to be below ground, dry well/wet well stations. In early 2008, the District will complete a SCADA upgrade project that includes installation of PLCs at all of the District’s lift stations. These PLCs will have the ability to remotely monitor and control each lift station and relay critical alarms to the main telemetry unit located at the District’s Maintenance and Operations Facility. In the event

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BasinDistrict King County AreaName Name Acres

North CreekNC-1 ALDN08 310NC-2 ALDN09 385NC-3 SLWD Trib. 543NC-4 SLV001 183NC-5 SLV004 196NC-6 SLV002 47NC-7 SLV003 51NC-8 ALD032 268NC-9 ALD6A 173NC-10 ALD022 212NC-11 ALD024 114NC-12 ALD026 248NC-13 ALD021 226NC-14 ALD019 172NC-15 ALD6C 334NC-16 ALD009 183NC-17 ALD025 242NC-18 ALD006B 990NC-19 ALD023N 345NC-20 ALD033 226NC-21 ALD037 199NC-22 ALD038 685NC-23 ALD031 457NC-24 ALD028 400NC-25 ALDN013 130NC-26 ALD041 276NC-27 ALD011 279NC-28 ALDN04 57NC-29 ALD001A 513NC-30 ALD040 299NC-31 ALDN030 185NC-32 ALD012 232NC-33 ALD030 417NC-34 ALDN06 602NC-35 ALD013 194NC-36 ALD035 468NC-37 ALD002 243NC-38 ALDN05 191NC-39 ALD034 281NC-40 NCREK012 357NC-41 ALDN07 289

12,202

SC-1 ALD018 519SC-2 ALD018A 474

Mini-Basins

North Creek SubtotalSwamp Creek

Table 5.5 Mini-Basin Delineation

BasinDistrict King County AreaName Name Acres

Mini-Basins

Table 5.5 Mini-Basin Delineation

SC-3 ALD014A 164SC-4 ALD014B 124SC-5 ALDN11 185SC-6 ALDN12 293SC-7 ALD003 81SC-8 ALD12 754SC-9 ALD020 173SC-10 ALDN01 256SC-11 ALD12A 549SC-12 ALD015 445SC-13 ALD016A 141SC-14 ALD039A 624SC-15 ALD012B 137SC-16 ALD005 336SC-17 ALD004 301SC-18 ALD006 444SC-19 ALD007A 543SC-20 ALDN02 59SC-21 ALD008 336SC-22 ALDN000 302SC-23 ALD010A 241SC-24 ALDN03 188

Swamp Creek Subtotal 7,669Everett

EV-1 ALDN10 629Everett Subtotal 629

Picnic PointPP-1 ALDN15 121PP-2 ALDN19 714PP-3 ALDN16 238PP-4 Picnic 164PP-5 ALDN21 260PP-6 ALDN17 310PP-7 Marina 116PP-8 ALDN14 336PP-9 ALDN13 513PP-10 ALD014C 162PP-11 ALDN18 78PP-12 ALDN20 592PP-13 ALDN22 273

Picnic Point Subtotal 3,877Little Bear Creek

BC-1 Bear Creek 121

TOTAL AREA 24,498


that an alarm occurs, this system notifies District maintenance staff so the issue can be investigated and quickly resolved. Alarm notifications include: pump on/off; pump failure; power failure; high / low wet well level; generator run; operator in trouble; intrusion; and smoke detector. Figures 5.2 through 5.5 illustrate the relationships between each of Alderwood’s lift stations and gives a schematic representation of their location within the system. A brief description of each lift station follows: Picnic Point Drainage Basin

• Lift Station No. 4 – This station provides service to the west side of Lake Serene. This lift station pumps wastewater to the Picnic Point Trunk via a 4” ductile iron force main. The rated capacity of this station is 130 gpm. The overflow elevation from the wetwell is 543.47. It is estimated that there is approximately 30 minutes of storage volume at high flow conditions.

• Lift Station No. 5 – The service area is between 52nd Ave W and Highway 99 between 165th Pl. SW and 143rd Pl. SW. The 1500 gpm station utilizes a 14-inch ductile iron force main to deliver flows to the Picnic Point Trunk. This station is Alderwood’s largest capacity station. The overflow elevation from the wetwell is 421.21. It is estimated that there is approximately 20 minutes of storage volume at high flow conditions.

• Lift Station No. 6 – The 500 gpm lift station serves residential areas between 14th St. SW and 152nd St. SW, west of 52nd Ave. The sewage is pumped through an 8-inch ductile iron force main to a discharge at a 10-inch gravity line. This line flows north to the Picnic Point Trunk. The station’s service area also includes flow from Lift Station No. 16. The overflow elevation from the wetwell is 347.76. It is estimated that there is approximately 20 minutes of storage volume at high flow conditions.

• Lift Station No. 16 – Flow is pumped through a 4-inch PVC force main to a gravity system served by Lift Station No. 6. Flows are ultimately discharged into the Picnic Point Trunk. This lift station is rated at 125 gpm and primarily serves the Soundview Hills residential development. The overflow elevation from the storage tank is 335.00. It is estimated that there is approximately 120 minutes of storage volume at high flow conditions.

• Lift Station No. 18 – Provides service to the residences north and south of Picnic Point Road in the vicinity of the treatment plant. The 6-inch ductile iron force main pumps wastewater flows to a location just upstream of the Picnic Point Wastewater Treatment Plant head works. This station also receives the waste streams generated by the plant for recycle back to the head works.

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The 560 gpm capacity of this lift station is adequate under normal plant operating conditions. However, during plant maintenance activities that generate large waste stream volumes, the lift station is unable to process the additional flows. During maintenance actives, such as cleaning the chlorine contact basin, staff must carefully monitor the amount of recycle waste generated so that the lift station is not overwhelmed. The overflow elevation from a tributary manhole is 188.80. It is estimated that there is approximately 20 minutes of storage volume at high flow conditions.

• Lift Station No. 20 – Collects flows from residential areas in the northwest corner

of the Alderwood service area. The 275 gpm lift station utilizes a 6-inch ductile iron force main that discharges into the Harbor Point Trunk for ultimate disposal at the Picnic Point WWTP. The overflow elevation from the storage tank is 263.50. It is estimated that there is approximately 45 minutes of storage volume at high flow conditions.

Swamp Creek Drainage Basin

• Lift Station No. 2 – Serves a small residential and commercial area at the

intersection of the Mukilteo Speedway and Highway 99. This station has a rated capacity of 260 gpm. The lift station transports flow through a 6-inch ductile iron force main that discharges to an 8-inch concrete gravity main that ultimately flows to the Swamp Creek Trunk after passing though Lift Station No. 3. When the Alderwood Swamp Creek Trunk is extended further north, this lift station can be decommissioned. The overflow elevation from the wetwell is 468.35. It is estimated that there is approximately 20 minutes of storage volume at high flow conditions.

• Lift Station No. 3 – Currently out of service. The 900 gpm station includes an 8-inch ductile iron force main that discharges into the Picnic Point Trunk for treatment at the Picnic Point Wastewater Treatment Plant. This station is scheduled for decommissioning in 2008. No overflow is reported for this station. It is estimated that there is approximately 10 minutes of storage volume at high flow conditions. Flows, currently and in the future, from the service area are diverted east to the King County Swamp Creek Trunk. The emergency generator at this lift station has been removed since the station is out of service.

• Lift Station No. 7 – Provides service to commercial and residential connections located between the Mukilteo Speedway and Highway 99. The 6-inch cast iron force main from this lift station can discharge up to 300 gpm into the 10-inch gravity main that flows south towards Lift Station No. 3 and ultimately to the Swamp Creek Trunk. As with Lift Station No. 2, when the Alderwood Swamp Creek Trunk is extended further north, this lift station can be decommissioned.

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The overflow elevation from the wetwell is 484.00. It is estimated that there is approximately 20 minutes of storage volume at high flow conditions.

• Lift Station No. 19 – As Alderwood’s smallest capacity lift station at 100 gpm, this station collects residential flows from the Brierwood Meadows area. The flow is discharged through a 4-inch ductile iron force main into the Larch Way Trunk. The overflow elevation from the storage tank is 251.60. It is estimated that there is approximately 120 minutes of storage volume at high flow conditions.

North Creek Drainage Basin

• Lift Station No. 17 – Collects flow from Martha Lake Park and the residential areas east of Interstate 5 and north of Martha Lake. This 200 gpm lift station will be redirected from the North Creek basin to the Swamp Creek basin in 2008. The overflow elevation from the storage tank is 450.50. It is estimated that there is approximately 120 minutes of storage volume at high flow conditions.

Everett Drainage Basin

• Lift Station No. 11- This lift station is located in McCollum Park and receives its flows from an area south of 128th St. SW and east of Interstate 5. The flows to this lift station are from both residential and commercial areas. The Station utilizes a 6-inch ductile iron force main that discharges to a gravity main for ultimate disposal by the City of Everett. The overflow elevation from the wetwell is 381.50. It is estimated that there is approximately 20 minutes of storage volume at high flow conditions. In the near future, Lift Station No. 11 will be reconfigured to direct flows away from Everett and towards the Silver Lake Water District area that is a tributary to Alderwood. Those flows will return south through Alderwood, via the North Creek Trunk, for ultimate conveyance and treatment to KCDNR.

• Lift Station No. 21 – The 500 gpm lift station serves an area near the Everett-Alderwood boundary. An 8-inch ductile iron force main is used to convey flows to an Everett gravity main for ultimate treatment and disposal. The overflow elevation from the storage tank is 455.00. It is estimated that there is approximately 45 minutes of storage volume at high flow conditions.

5.5 DISTRICT COLLECTION AND CONVEYANCE FACILITIES The District’s inventory of gravity sewer lines totals nearly two million linear feet of pipes ranging from 6-inches to 24-inches in diameter. Table 5.6 below presents the summarized inventory of the District-owned piping systems.

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Table 5.6 Summary of Pipe Inventory

Pipe Size Total Length of District-owned

Pipe (feet) 6-inch 8-inch 10-inch 12-inch 15-inch 16-inch 18-inch 21-inch 24-inch TOTAL

871 1,742,316

60,767 96,085 34,446 14,039 17,452

26 6,928

1,972,930 feet 5.6 KING COUNTY CONVEYANCE FACILITIES The King County Wastewater Treatment Division is responsible for interception, treatment, and disposal of all wastewater collected within their defined service area. King County has instituted several programs to control infiltration and inflow, and to add capacity for treatment and disposal. County facilities within the District vicinity are shown on Figure 3.1. The County operates and maintains these interceptors within the District’s service area. The County has recently completed an analysis of their interceptor lines within the District and has initiated the design and construction to upgrade those lines to meet future capacity requirements. Current King County planning involves diversion of the District’s sewage that is conveyed to King County to the County’s Brightwater Wastewater Treatment Plant. 5.7 PICNIC POINT WWTP 5.7.1 General The Picnic Point Wastewater Treatment Plant (WWTP) provides wastewater treatment service for residential, commercial, and industrial customers in the Picnic Point drainage basin. The facility was built in 1973 and provides an average daily treatment of 3 mgd. The plant is located on Picnic Point Road near the Picnic Point Park. Presently, the Picnic Point WWTP’s influent wastewater flows are nearing the plant’s 3 mgd capacity. In early 2001, the District initiated the planning and design of an upgrade to the Picnic Point Wastewater Treatment Plant. Construction for the upgrade is expected to begin in early 2008 and be finished by 2011.

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The treatment plant upgrades will provide capacity sufficient to provide service to all residents of the Picnic Point basin. The maximum month flow from the build-out population has been estimated at 6.0 mgd.

The Washington State Department of Ecology regulates discharges to waters of the state through the National Pollutant Discharge Elimination System (NPDES) permit system. NPDES permits are developed based on federal and state water quality standards and treatment requirements. The existing system is permitted under the NPDES discharge permit number WA-002-082-6. Effluent limitations are summarized in Table 5.7. Table 5.7 Current NPDES Effluent Limitations for Picnic Point WWTF Discharge

Parameter

Average Monthly Limits1

Average Weekly Limits1

Maximum Daily Limits1

Biochemical Oxygen Demand (5 day BOD)

30 mg/L, 750 lbs/day 45 mg/L, 1125 lbs/day N/A

Total Suspended Solids (TSS) 30 mg/L, 750 lbs/day 45 mg/L, 1125 lbs/day N/A Fecal Coliform Bacteria 200/100 mL 400/100 mL N/A pH Daily minimum ≥ 6 and daily maximum of ≤ 9 N/A Total Residual Chlorine 0.5 mg/L N/A 1.0 mg/L 1Current load limits are based on the current MMF of 3 MGD and are subject to change to reflect increased MMF flows Biosolids treatment and use are regulated under federal (40 CFR Part 503) and state (Chapter 173-308 WAC) regulations through the Statewide General Permit for Biosolids Management. The facility currently produces sub-Class B biosolids (as defined by federal and state regulations), which are sent off-site for composting prior to their beneficial reuse. The upgraded Picnic Point WWTF will produce Class A biosolids. 5.7.2 Existing Wastewater Treatment Conditions The existing Picnic Point WWTP was designed to provide secondary treatment for a total average design flow of 3 mgd and a peak hour flow of 7.5 mgd. Wastewater treatment is currently provided by two independent contact stabilization units. Treatment Unit No. 1 and Treatment Unit No. 2 have a 1 mgd and a 2 mgd capacity respectively. Each unit has a contact tank, a stabilization tank, a secondary clarifier, and an aerobic digester. In addition to the two treatment units, the wastewater treatment plan includes a head works, chlorine contact tanks, a solids handing facility, and a plant operations building.

The treated effluent is currently discharged approximately 1,000-feet off shore in the Possession Sound through an 18-diameter marine outfall pipe.

Picnic Point Wastewater Treatment Facility Upgrade Project The Picnic Point WWTF Upgrade Project consists of new and expanded facilities that will produce high-quality treated effluent and Class A biosolids from up to 6 mgd (MMF)

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of wastewater entering the Picnic Point WWTF. Figure 5.6 presents the process flow schematic of the Picnic Point WWTF, and provides an overview of the liquid and solids streams treatment processes. The liquid stream process elements include influent fine screening, grit removal, biological treatment via a membrane bioreactor (MBR), and ultraviolet (UV) disinfection.

After disinfection, effluent will be conveyed to Puget Sound through the existing outfall conveyance system. The outfall pipeline capacity was evaluated to ensure adequate capacity for future flows. Proposed modifications include the addition of air release valves along the onshore pipeline only.

Phase I of the project includes four membrane tanks processing a maximum month flow of 4.0 mgd; two additional tanks will be brought on-line in Phase II when the 85 percent flow requirements are met (as described in the District’s NPDES permit) to accommodate a total maximum month flow of 6.0 mgd. All six tanks will be constructed in Phase I. The equipment associated with the Phase II membrane tanks, however, will be installed later. Table 5.8 below lists the flows and loads projected for startup (2010), Phase I, and Phase II.

Table 5.8 Projected Influent Loadings to the Picnic Point WWTF1

Parameter Startup Phase I Phase II2Average dry weather flow (ADWF), mgd

Annual average flow (AAF), mgd

Average wet weather flow (AWWF), mgd

Maximum month flow (MMF)3, mgd

Peak day flow (PDF), mgd

Peak wet weather flow (PWWF), mgd

2.4

2.7

2.9

3.3

4.4

8.2

3.0

3.2

3.6

4.0

5.4

10.0

3.9

4.3

4.7

6.0

7.1

13.2

Annual average BOD loading, lb/d

Average dry weather BOD loading, lb/d

Maximum month BOD loading, lb/d

Peak day BOD loading, lb/d

5,900

5,500

6,000

10,100

7,140

6,700

7,300

12,500

9,500

8,800

11,000

18,800

Annual average TSS loading, lb/d

Average dry weather TSS loading, lb/d

Maximum month TSS loading, lb/d

Peak day TSS loading, lb/d

5,500

5,400

7,400

12,900

6,700

6,500

9,000

16,100

8,900

8,600

13,500

24,100 1Load values have been rounded to the nearest hundred pounds 2Buildout is anticipated to occur by 2022, and flow and load increases between 2022 and 2028 are anticipated to be minimal. The 2022 flows and loads presented in the Engineering Report are used as the basis for Table 2. 3Maximum month flow (MMF) is the average flow for the maximum month, as defined in the current NPDES permit. The MMF is sometimes referred to as peak month flow.

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WATER & WASTEWATER

DISTRICT5.6

Process Flow Schematic




5.7.3 Picnic Point Basin Temporary Sewer Allocation Process

On March 19, 2007, the District placed in temporary abeyance the issuance of certificates of sewer availability in the Picnic Point sewer basin. The temporary measure was in response to capacity concerns associated with the Picnic Point Wastewater Treatment Facility. This was intended to promote the public health, welfare and safety of the District and to ensure the existence and provision of adequate sewer transmission and treatment capacity for existing District customers.

After adoption of these measures, the District evaluated the capacity remaining in the existing Picnic Point WWTF. A consultant team determined that an increase in flow to the WWTF of 174,340 gpd will likely not result in failure to meet the NPDES effluent requirements for the plant.

The District established the policies and procedures under which the remaining available capacity in the Picnic Point WWTF (described as "Available ERUs") were made available for allocation to parties desiring to obtain sewer service from the District. On September 17, 2007, the Board adopted Resolution No. SR 954-2007 that established the Picnic Point allocation process that establishes the policies and procedures for distributing the remaining capacity, including the process for obtaining a sewer certificate of availability. This allocation plan affected only new connections to the sewer system; existing customers that are not seeking additional connections to the sewer system will not be impacted by this allocation process.

The District has also finished the construction documents and has award the construction contract for the new wastewater treatment plant. Completion of the plant is slated for 2010.

5.8 Additional Regulatory Requirements Snohomish County requires that all wastewater facilities built or upgraded in the county meet strict odor control standards and are seismically safe. The County has adopted two ordinances to enforce these requirements and protect the public health and safety of its citizens. In addition, Substitute Secondary House Bill 1338 requires an investigation of wastewater reuse.

Snohomish County Odor and Seismic Evaluation

Ordinance No. 06-074 requires odor prevention measurements for all treatment and conveyance systems over a certain threshold. The threshold for wastewater treatment plants is 25 mgd, and conveyance for piping greater than 24-inches in diameter. Since the Picnic Point WWTP is less than 25 mgd the facilities at Picnic Point WWTF is exempt from this requirement. Conveyance piping that is owned now or in the future by the District that exceeds 24-inches would, however, be subject to these odor control measures. See Appendix H.

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The seismic hazard ordinance deals with developments where the facility or operation poses a serious risk of harm to the public or the environment from seismic activity due to the type of hazardous materials, liquids or gases used on the site. This ordinance gives the County additional authority to require reasonable mitigation to protect the community before an earthquake happens. It applies to a number of different types of facilities, including wastewater facilities. Ordinance No. 06-075 defines the setback requirements and height limitations for all developments, excluding single family and duplex dwellings, located within the seismic hazard areas. See Appendix H. Substitute Secondary House Bill 1338 – Wastewater Reuse While reuse of reclaimed wastewater treatment plant effluent is becoming more and more common, the demand for year-round reclaimed effluent in the Pacific Northwest is very limited, particularly in a suburban setting. Nevertheless, Alderwood is making accommodations for use of reclaimed water throughout their service area. To be acceptable for reuse, diverted effluent must meet the quality standards specified in the state’s Water Reclamation and Reuse Standards. During the Picnic Point Wastewater Treatment Facility upgrade, space for a UV disinfection facility has been reserved to produce Class A reclaimed water. However, plans for development of these facilities have not been included in the District’s CIP at this time. 5.9 PUBLIC AND PRIVATE WATER FACILITY LOCATIONS 5.9.1 District Water Facilities The District covers approximately 60 square miles spanning from Puget Sound east beyond the Bothell/Everett Highway (Highway 527) and north from the Snohomish County line to just south of Paine Field. The District’s retail service area encompasses the cities of Brier, Mill Creek, Bothell north of the Snohomish County line, the City of Mukilteo south of Paine Field, portions of Lynnwood and unincorporated areas of southwest Snohomish County. The District also sells wholesale water to the cities of Edmonds, Lynnwood and Mountlake Terrace, and Silver Lake Water and Sewer District and Cross Valley Water District. The service boundaries are presented on Figure 5.7 that also includes the location of the major water infrastructure elements; reservoirs, pump stations, disinfection facilities, pressure reducing Stations, interties and transmission lines. As shown on Figure 5.8, the District is bordered by Mukilteo Water District and the City of Everett to the north, the Silver Lake Water and Sewer District and Cross Valley Water District to the east, Northshore Utility District to the south and the cities of Mountlake Terrace, Lynnwood and Edmonds to the west.

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The District purchases all of its water from the City of Everett. Everett’s regional supply comes from the Sultan River, which is stored in the Spada and Chaplain Reservoirs. Everett’s system includes a direct filtration and three large diameter pipelines, known as Transmission Line No. 2, 3, and 5. For the district, water is conveyed through Transmission Line No. 5 to Everett’s Reservoir 3, which supplies the District’s Pump Station No. 1 and 2 In 2003, the Clearview transmission main, pump station and storage facility were completed and provide the District with an additional supply connection from the City of Everett supply system. The Clearview pipeline connects to Everett’s Transmission Line No. 5 and conveys water south where it serves the Silver Lake Water and Sewer District, the Cross Valley Water District and the Alderwood Water and Wastewater District. The District’s water system is comprised of 619 miles of pipeline with five pressure zones, including 97.3 million gallons of storage, three water supply pump stations, one booster pump station, and an artesian well. 5.9.2 Wells The District currently maintains the artesian well located on 164th Street SW which is currently used directly as a local community source of supply. There is no distribution piping associated with this well, nor is it connected to the District’s distribution system. The District maintains this artesian well as a courtesy to residents who prefer untreated water. It is not part of the District’s sources of supply and the District is not dependent on it as a source. There are some private wells either for domestic consumption or irrigation.

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CHAPTER V - EXISTING FACILITIES - Alderwood Water · CHAPTER V - EXISTING ... 116644TThh sSStt SWW 1132N dd St E ... c V i e w D r O l y p i V i D 5 8 T h 3 A v W 8 28Th St 9 T h