CHAPTER 8 – Source Infrastructure

Source infrastructure projects help meet the Drinking Water Utility’s Goal 6:

Goal

Infrastructure is prudently financed, and sustainably constructed, maintained and operated to ensure reliable delivery of high quality water to a growing community.

The 2015-2020 strategy for source projects is to develop and maintain multiple, geographically dispersed water supplies to enhance system reliability.

Other projects for improving the infrastructure are discussed in Chapter 9 (Storage Infrastructure) and Chapter 10 (Transmission/Distribution Infrastructure). Water quality strategies are in Chapter 11 and operations and maintenance strategies are in Chapter 12.

This chapter describes existing sources, evaluates their ability to meet current and projected needs, and identifies projects to be constructed in 2015-2020. Washington State Department of Health (DOH) rules on source development are in Chapter 173-160 WAC and Chapter 246-290 WAC, Part 3 (design of public water systems). Detailed specifications are in the DOH Design Manual.

8.1 Description of Existing Source

Olympia’s current drinking water sources are McAllister Wellfield and six additional groundwater wells. They tap aquifers to obtain water that is of adequate quality and sufficient quantity to provide a long-term supply of water to the City’s system. Chapter 4 describes each source, with information about water rights; Chapter 7 provides hydrogeological details about each source aquifer; and Chapter 11 includes water quality and treatment protocols.

Each of these sources is described below. Map 1.4 in Chapter 1 shows where these sources are located. Table 8.1 is an inventory of equipment at each source.

McAllister Wellfield

Olympia’s main source of drinking water is McAllister Wellfield (S16), a more protected and productive source than McAllister Springs. The Wellfield is located approximately a mile southeast of McAllister Springs and eight miles east of Olympia.

The Washington State Department of Ecology (Ecology) approved developing the water rights in three phases, with full development by 2050:

•    Phase 1 included drilling one new well and rehabilitating two existing wells drilled in the late 1990s. Phase 1 has a target production rate of 15 million gallons per day (Mgd) and replaced the capacity of McAllister Springs. Construction of Phase 1 was completed in 2014. Phase 1 will provide sufficient water to meet summer water demands until Phase 2 supplies come on line.

•    Phase 2, planned to come on line around 2030, will increase production levels to 19.6 Mgd for the City and provide 0.5 Mgd for the Nisqually Tribe.

•    Phase 3, scheduled for completion by 2050, will raise production to 23.06 Mgd for Olympia and 3 Mgd for the Tribe, thereby maximizing full use of the water rights.

Table 8.1 Source Equipment Inventory

Source Name

Pump Type

Pump Model

Pump Size (HP)

Current Capacity (GPM)

Year Installed

Current Capacity

(Mgd)

Well Diameter

(Inches)

Well Depth

(ft.)

McAllister TW-22 (S13)

Turbine

Ruhrpumpen

200

1,500

2014

2.16

12

370

McAllister PW-24 (S14)

Turbine

Ruhrpumpen

400

2,900

2014

4.18

20

400

McAllister PW-25 (S15)

Turbine

Ruhrpumpen

700

6,100

2014

8.78

24

425

Total McAllister Wellfield (S16)

 

 

 

15.12

 

 

Hoffman Well 3 (S08)

Submersible

Byron Jackson

100

1,000

1985

1.44

10

378

Shana Park Well 11 (S10)

Submersible

American Marsh

25

1,000

2005

1.44

16

100

Indian Summer Well 20 (S12)

Submersible

Peerless

125

8501

2008

1.221

12

213

Kaiser Well 1 (S03)

Submersible

Peabody

25

360

1992

0.52

12

92

Allison Springs Well 13 (S09)

Submersible

American Marsh

40

650

2005

0.94

16

200

Allison Springs Well 19 (S11)

Submersible

American Turbine

60

900

2005

1.30

16

183

Total Other Wells

6.86

Pumping Facilities

McAllister Wellfield pumps were installed in 2014 in three wells. The wells are called PW (Production Well)-24, TW (Test Well)-22, and PW-25. PW-24 and TW-22 were drilled in 1998 as part of the investigation to determine the best location for the City’s new water source. PW-25 was drilled and tested in 2013 after Ecology granted the City and Nisqually Tribe water rights for the new source. PW-24 is a 20-inch diameter well that produces 2,900 gallons per minute (gpm); TW-22 is a 12-inch diameter well that produces 1,500 gpm; and PW-25 is a 24-inch diameter well that produces 6,100 gpm. The pumps are located in concrete masonry block buildings. The wells pump into 36-inch, 30-inch and 24-inch ductile iron pipe and then to a 36-inch welded steel transmission main that heads north about 4,100 feet and connects to the original 36-inch main just west of McAllister Springs before heading to the Meridian Storage Tanks.

The susceptibility assessment forms and well logs for the McAllister Wellfield wells are in Appendix 7-1.

Power Supply

Power for the facility, including pumps, pump controls, chlorination equipment and telemetry systems, is provided by an air-cooled, 1,500 KVA, three-phase transformer located adjacent to the PW-25 well house.

Underground power follows the 36-inch transmission main about 4,100 feet north of the McAllister Wellfield and connects to three-phase power at Old Pacific Highway.

An emergency diesel generator capable of powering PW-24, chlorination equipment, telemetry and other systems is located at PW-25. The generator is capable of powering the 2,900 gpm well pump at PW-24. The City’s winter water demands can be met using only PW-24 plus the other five City wells, rendering TW-22 and PW-25 unnecessary during a winter power outage. Power outages are more common in winter than in the summer. If necessary, the Utility has provisions to add generator capacity with Phase 2 of the wellfield development.

Water Quality Treatment

Water pumped from McAllister Wellfield is disinfected with chlorine before it reaches the Meridian Storage Tanks. At the chlorine source is an automatic switchover manifold feed system. The supply room is equipped with dual scales, ventilation, alarm systems and emergency response equipment. Aeration towers are currently scheduled to be constructed in 2016 at the Meridian Storage Tanks. The aeration towers will raise the pH of the wellfield water from about 6.5 to 7.8. Because the City’s population is over 50,000, Olympia is required by DOH to optimize for pH adjustment of its sources (Chapter 11).

East Olympia Area Wells

The three wells located in East Olympia are described below.

Hoffman Well 3 (S08)

In 1985, the City drilled the 16-inch-diameter Hoffman Well 3 (S08) in Zone 417. The well and pumping facilities are in a locked enclosure and have been used primarily to meet peak hour demands since May 1985.

The well casing extends 378 feet from the ground surface through various glacial deposits to bedrock. A 34-foot stainless steel screen was installed between the depths of 324 and 358 feet. Aquifer pump testing indicates a sustained yield of 1,000 gpm. This well is considered to be in good condition and requires only routine maintenance. Water quality testing indicates that the well produces water with levels of iron and manganese in excess of secondary maximum contaminant levels, which is an aesthetic rather than a health-related concern. Consequently, its use is restricted to peak hours only when needed to supplement the supply. The well pumps directly into a storage tank where mixing dilutes the higher iron and manganese levels.

Shana Park Well 11 (S10)

In 1988, Shana Park Well 11 (S10) was drilled to a depth of 100 feet in Zone 417. Casing perforations begin at 38 feet. The capacity of this well is approximately 1,000 gpm. The well pump was replaced in 2005 with a more energy efficient 25-hp pump, using a 50 percent funding grant from Puget Sound Energy.

In 1989, a treatment facility was installed to elevate pH by injecting soda ash into the water. The slightly acidic nature of the aquifer (pH 6.2) had created localized complaints of blue discoloration from corroded copper leaching in household plumbing. In 1996, the Utility constructed an aeration tower, which strips the dissolved carbon dioxide from the water and raises the pH to about 7.6. This pH level allows the City to meet the requirements of the federal Lead/Copper Rule (Chapter 11).

In the long term, the Utility intends to shift the Shana Park Well to emergency use only because of concerns over rising nitrate levels and overall vulnerability to contamination (Chapter 7).

Well 11 is considered to be in good condition and requires only routine maintenance.

Water from Well 11 is chlorinated using gas chlorine from 150 pound cylinders. All the chlorination equipment is located in the well building.

Indian Summer Well 20 (S12)

Indian Summer is a gated Master Planned Community with a golf course, located in Southeast Olympia off Yelm Highway. The community is completely built out, with about 500 single-family homes, town homes and condominiums. Indian Summer Well 20 (S12) is located in the center of the community, at the entrance to the community-owned 36-acre Nature Preserve.

The well was drilled in 1993 to a depth of 213 feet and is located in Zone 417.  The initial aquifer pumping test in 1993 indicated a potential short-term pumping capacity of 900 gpm with long-term continuous capacity of 650 gpm. A minor amount of fine sand was produced at start-up. In 2006, the Utility redeveloped the well to eliminate the sand and confirm the well capacity. The short-term production was confirmed at 900 gpm while the continuous long-term pumping improved to 700 gpm. The Indian Summer Well water right limits the instantaneous pumping rate to 850 gpm. An on-site chlorine generation system using a brine solution is used to disinfect the water.

West Olympia Area Wells

Three wells located in West Olympia, in the Allison Springs/Kaiser Road area of West Olympia, are described below.

Kaiser Well 1 (S03)

Kaiser Well 1 (S03), located in Zone 298, was first put into service in 1976. Aquifer pumping tests indicated a sustained capacity of 340 to 380 gpm, with a stabilized drawdown after four hours of pumping, although flow was originally restricted to 280 gpm to prevent over-pumping. The well is equipped with a water-lubed 25-hp submersible pump. The original pump was replaced in 1992 with a larger capacity pump that is producing 360 gpm.

DOH approved gas chlorination in August 2010. This well is considered to be in good condition. The Kaiser Well 1 (S03) is an emergency source and was physically disconnected from the water system on June 23, 2015.

Allison Springs Well 13 (S09)

Allison Springs Well 13 (S09) was installed near Allison Springs to augment the supply to Olympia’s west side (Zone 298). It consists of a 16-inch steel casing drilled to a depth of 200 feet with the screens set between 171 and 185 feet. The original 125-hp pump was replaced in 2005 with a more energy-efficient 40-hp pump, using a 50 percent grant from Puget Sound Energy. Installed well capacity is 900 gpm. The current pumping rate is approximately 650 gpm. Well 13 isconsidered to be in good condition and requires only routine maintenance.

Allison Springs Well 19 (S11)

Allison Springs Well 19 (S11) is located near Well 13 in Zone 298. It consists of a 16-inch steel casing drilled to a depth of 183 feet and is screened in a sand and gravel aquifer that lies 120 to 160 feet below the surface. In 2005, the well pump was replaced with a more energy efficient 60-hp pump, using a 50 percent grant from Puget Sound Energy. The current pumping rate is approximately 900 gpm. The Utility is considering options to increase the yield, as needed. In 1996, an aeration facility was installed to strip the dissolved carbon dioxide from water from Wells 13 and 19 to raise pH.

Water from both wells is pumped to the aeration tower, where it then flows to a clear well. Water is pumped to the water system from the clear well. The clear well has two variable speed pumps that automatically adjust output to match variations in well production. Well 19 is considered to be in good condition and requires only routine maintenance.

Both Allison Springs Wells 13 and 19 are chlorinated using gas chlorine from 150 pound cylinders. All the chlorination equipment is located in the building housing Well 13.

8.2 Source Capacity Analysis

The ability of existing sources to meet current and projected water supply requirements was evaluated for this Plan. This section presents the capacity analysis design criteria and a discussion of the evaluation results.

Design Criteria

The DOH requires that sources of supply be sufficient to meet maximum day demands (MDD) for each pressure zone within a system, as well as for the system as a whole. Therefore, this evaluation compares the City’s total groundwater source capacity with full system water demand, as well as the source and booster pump station capacities within each pressure zone with water demand specific to that zone.

This source capacity analysis utilizes the “baseline” water demand forecast presented in Chapter 3 (Table 3.9), and does not include the effects of additional water conservation or the potential impacts of climate change on future water demands. This approach is taken for the following reasons:

•    Future water conservation goals may not be fully realized, as they are dependent upon unpredictable customer behavior changes. Excluding potential future water demand reductions ensures that source capacities are sufficient to meet needs if conservation goals are not attained.

•    Significant uncertainties also exist with regard to the potential effects of climate change on future demand, as discussed in Chapter 3. The Utility will monitor demand and weather variables closely in order to refine demand forecasts and source capacity analyses when needed.

These two factors will tend to alter water demands in an opposing fashion over time. While conservation savings serve to reduce future water demand, climate change may result in increased demands. Thus, the effects of one variable may be offset by the impacts of the other, resulting in minimal net change to the water demand forecast.

Evaluation of Source Capacity

Source capacity was evaluated for the entire system and then for each pressure zone or zone combination. Each evaluation compares the projected MDD with existing source capacities under two conditions:

•    Assuming only existing sources are available, in order to identify source deficiencies.

•    Including planned future source capacities, to highlight the ability of these new sources to address identified deficiencies.

All evaluations assume 24-hour-per-day source operation. The location of each zone is shown on Map 1.4, Chapter 1.

Full System

Table 8.2 summarizes the comparison of the City’s total available source capacity with current and future system-wide demands. Current sources provide adequate supply capacity beyond 2064, the 50-year planning horizon. Additional planned sources will serve to bolster the system’s reliability in the future (see also Chapter 4).

The City has transferred its McAllister Springs water rights to the McAllister Wellfield. The current capacity of the McAllister Wellfield is 10,500 gpm (15.12 Mgd). Phase 2 of the wellfield development, planned for 2030, will increase the capacity by 3,111 gpm to 13,611 gpm (19.60 Mgd) for the City.

Phase 3 production of the wellfield reflects the long-term development under the full Abbott Springs water right to meet Olympia’s and the Nisqually Tribe’s 50-year planning horizon, and would be completed sometime between 2030 and 2050. Maximum production at full build-out will be 23.06 Mgd for Olympia and 3.0 Mgd for the Nisqually Tribe.

The City’s other planned sources are:

Briggs Well. Construction of this new well in southeast Olympia is scheduled to begin in 2019, with the source considered to be online sometime between 2020 and 2034.

Olympia Brewery. In partnership with the cities of Lacey and Tumwater, Olympia has obtained water rights associated with the former Olympia Brewery property. The timing and capacity of this source are uncertain, as the wellfield and associated infrastructure is currently in planning and development by the three cities.

(See Chapter 4 for details on these new sources.)

These new sources support the City’s intent to secure a 50-year supply of water, as mandated in the Comprehensive Plan. Also, as geographically dispersed sources, they will provide additional system reliability. In total, the City is projected to have a source surplus of 12.91 Mgd in 2064, even without including the Olympia Brewery supply.

Zones 338 and 417

Pressure Zones 338 and 417, in the southeast and east part of the service area, are evaluated in combination. Both zones receive water from the same sources: the Shana Park Well (S10), Hoffman Well (S08), Indian Summer Well 20 (S12), South Sound Booster Station and Fones Road Booster Station. These sources feed directly into Zone 417 and indirectly into Zone 338 via a flow control valve that allows water to enter the Boulevard Storage Tank (which then establishes the hydraulic grade in Zone 338). A pressure reducing valve (PRV) on Yelm Highway is another way for water to move from Zone 417 to Zone 338. The zones cannot be analyzed independently (from a source perspective) and have been combined into one analysis zone.

The South Sound and Fones Road Booster Stations receive water through a 36-inch water main from the Meridian Storage Tanks and provide the primary supply to these zones. Shana Park Well 11 (S10) provides a significant portion of the total supply capacity, while Hoffman Well 3 (S08) is used only during emergencies and on high demand days. Indian Summer Well (S12) was added to supplement supply to these zones.

Table 8.3 summarizes the source adequacy evaluation for Zones 338 and 417. Existing supplies are sufficient to meet demands throughout the entire planning period. The addition of the planned Briggs Well (S13), which will feed directly into these zones, will supplement supplies in these zones. With this additional source, the zones will have a supply surplus of 5.65 Mgd in 2034.

Table 8.2 Evaluation of Source Adequacy for Full System

Year

2015

2020

2034

2064

Max(2)

Equivalent Residential Units (ERUs)

51,560

41,166 (1)

48,782

63,431

73,639

Projected Demand - Gallons per Day (gpd) (3)

Average Day

8,559,000

6,834,000

8,098,000

10,530,000

12,224,500

Maximum Day

14,856,000

13,383,000

15,205,000

18,067,000

21,456,000

Evaluation of Existing Sources

Available Existing Source (gpd)(4)

 

 

 

 

 

McAllister Wellfield (S16) (10,500 gpm)

15,120,000

15,120,000

15,120,000

15,120,000

15,120,000

Allison Springs Well 19 (S11) (900 gpm)

1,296,000

1,296,000

1,296,000

1,296,000

1,296,000

Allison Springs Well 13 (S09) (650 gpm)

936,000

936,000

936,000

936,000

936,000

Shana Park Well 11 (S10) and Corrosion Facility (1,000 gpm)

1,440,000

1,440,000

1,440,000

1,440,000

1,440,000

Hoffman Well 3 (S08) (1,000 gpm)

1,440,000

1,440,000

1,440,000

1,440,000

1,440,000

Kaiser Rd. Well 1 (03) (360 gpm)(9)

518,400

0

0

0

0

Indian Summer Well 20 (S12) (850 gpm)

1,224,000

1,224,000

1,224,000

1,224,000

1,224,000

Total Available Source (gpd)

21,974,400

21,456,000

21,456,000

21,456,000

21,456,000

Source Surplus/(Deficiency) (gpd)

7,118,400

8,073,000

6,251,000

3,389,000

0

Evaluation of Future Sources

Future Source (gpd)(4)

 

 

 

 

 

Briggs Well (1,100 gpm)(5)

0

0

1,584,000

1,584,000

1,584,000

McAllister Wellfield Phase 2 (3,111 gpm)(6)

0

0

4,480,000

4,480,000

4,480,000

McAllister Wellfield Phase 3 (2,403 gpm)(7)

0

0

0

3,456,000

3,456,000

Brewery Wellfield(8)

0

0

TBD

TBD

TBD

Total Available Source (Existing + Future) (gpd)

21,974,400

21,456,000

27,520,000

30,976,000

30,976,000

Source Surplus/(Deficiency) (gpd)

7,118,400

8,073,000

12,315,000

12,909,000

9,520,000

Table 8.3 Evaluation of Source Adequacy for Zone 417 and Zone 338

 

Year

2015

2020

2034

Max(1)

Equivalent Residential Units (ERUs)

14,500

15,825

19,976

32,235

Projected Demand - Gallons per Day (gpd) (2)

Average Day

2,407,000

2,627,000

3,316,000

5,351,000

Maximum Day

4,785,000

5,145,000

6,226,000

10,296,000

Evaluation of Existing Sources

Available Existing Source (gpd)(3)

 

 

 

 

South Sound Booster (2,350 gpm)(4)

3,384,000

3,384,000

3,384,000

3,384,000

Fones Road Booster (1,950 gpm)(5)

2,808,000

2,808,000

2,808,000

2,808,000

Shana Park Well 11 (S10) and Corrosion Facility (1,000 gpm)

1,440,000

1,440,000

1,440,000

1,440,000

Hoffman Well 3 (S08) (1,000 gpm)

1,440,000

1,440,000

1,440,000

1,440,000

Indian Summer Well 20 (S12) (850 gpm)

1,224,000

1,224,000

1,224,000

1,224,000

Total Available Source (gpd)

10,296,000

10,296,000

10,296,000

10,296,000

Source Surplus/(Deficiency) (gpd)

5,511,000

5,151,000

4,070,000

0

Evaluation of Future Sources

Future Source (gpd)(4)

 

 

 

 

Briggs Well (1,100 gpm)(6)

0

0

1,584,000

1,584,000

Total Available Source (Existing + Future) (gpd)

10,296,000

10,296,000

11,880,000

11,880,000

Source Surplus/(Deficiency) (gpd)

5,511,000

5,151,000

5,654,000

1,584,000

Zone 347

The Eastside Booster Station supplies water to pressure Zone 347 with three pumps, each rated at 1,000 gpm. The combined supply capacity is 2,400 gpm. The source adequacy evaluation, summarized in Table 8.4, indicates that the booster station provides sufficient supply capacity throughout the entire planning period.

Table 8.4 Evaluation of Source Adequacy for Zone 347

 

Year

2015

2020

2034

Max(1)

Equivalent Residential Units (ERU's)

3,849

3,855

4,259

10,627

Projected Demand - Gallons per Day (gpd) (2)

Average Day

639,000

640,000

707,000

1,771,500

Maximum Day

1,271,000

1,254,000

1,327,000

3,456,000

Evaluation of Existing Sources

Available Existing Source (gpd)(3)

 

 

 

 

Eastside Booster (2,400 gpm)

3,456,000

3,456,000

3,456,000

3,456,000

Total Available Source (gpd)

3,456,000

3,456,000

3,456,000

3,456,000

Source Surplus/(Deficiency) (gpd)

2,185,000

2,202,000

2,129,000

0

Zone 264

Zone 264 is in the center of the City’s service area and obtains water from the distribution system primarily via a 16-inch connection from the 36-inch transmission main. Additional supply comes from the Capitol Way PRV, which is capable of transferring water from Zone 338 into Zone 264 under high demand situations. As indicated in Table 8.5, these supplies provide sufficient capacity throughout the planning period.

Table 8.5 Evaluation of Source Adequacy for Zone 264

 

Year

2015

2020

2034

Max(1)

Equivalent Residential Units (ERU's)

2,596

675

2,970

16,901

Projected Demand - Gallons per Day (gpd) (2)

Average Day

431,000

444,000

493,000

2,805,600

Maximum Day

859,000

869,000

926,000

5,551,200

Evaluation of Existing Sources

Available Existing Source (gpd)(3)

 

 

 

 

10" Water Main (2,545 gpm)

3,664,800

3,664,800

3,664,800

3,664,800

Capitol Way PRV (1,310 gpm)

1,886,400

1,886,400

1,886,400

1,886,400

Total Available Source (gpd)

5,551,200

5,551,200

5,551,200

5,551,200

Source Surplus/(Deficiency) (gpd)

4,692,200

4,682,200

4,625,200

0

Evaluation of Future Sources

Zone 226, 298, and 380

Due to the hydraulic characteristics of Zones 226, 298 and 380, these three zones are analyzed in combination, as well as independently of each other. Previous hydraulic analyses indicate that the capacity of the 36-inch supply line from the Fir Street Storage Tanks, which feeds Zone 226, is nearly 4,000 gpm. The West Bay Booster Station feeds Zone 380 from Zone 226. The Percival Booster Pump Station feeds Zone 298 from Zone 226. Zone 298 is also supplied directly by the Allison Springs Wells 13 (S09) and 19 (S11), and the Kaiser Road Well 1 (S03), which is an emergency source. Additional supply is provided to Zone 298 via a pressure reducing valve that allows for water to enter this zone from Zone 380. Additional supply to Zone 226 is provided by another pressure reducing valve from Zone 298. If needed, water can also be transferred from Zone 298 to Zone 380 via the Elliot Booster Station.

When analyzed together, the three zones have sufficient supply capacity throughout the planning period, as shown in Table 8.6.

Table 8.7 shows the analysis of Zones 298 and 380 together. Assuming 24-hour pumping, Zones 298 and 380 have adequate supply through 2034.

Table 8.8 shows the analysis of Zone 380 by itself. Assuming 24-hour pumping, Zone 380 has adequate supply through 2034.

Table 8.6 Evaluation of Source Adequacy for Zone 226, 298 and 380

 

Year

2015

2020

2034

Max(1)

Equivalent Residential Units (ERUs)

17,500

18,867

21,675

25,401

Projected Demand - Gallons per Day (gpd) (2)

Average Day

2,905,000

3,132,000

3,598,000

4,216,500

Maximum Day

5,776,000

6,133,000

6,755,000

7,992,000

Evaluation of Existing Sources

Available Existing Source (gpd)(3)

 

 

 

 

36" Water Main (4,000 gpm)

5,760,000

5,760,000

5,760,000

5,760,000

Allison Well 19 (S11) (900 gpm)

1,296,000

1,296,000

1,296,000

1,296,000

Allison Well 13 (S09) (650 gpm)

936,000

936,000

936,000

936,000

Kaiser Rd. Well 1 (S03) (360 gpm) (4)

518,400

0

0

0

Total Available Source (gpd)

8,510,400

7,992,000

7,992,000

7,992,000

Source Surplus/(Deficiency) (gpd)

2,734,400

1,859,000

1,237,000

0

Table 8.7 Evaluation of Source Adequacy for Zone 298 and Zone 380

Year

2015

2020

2034

Max(1)

Equivalent Residential Units (ERUs)

12,717

13,783

15,705

28,506

Projected Demand - Gallons per Day (gpd) (2)

Average Day

2,111,000

2,288,000

2,607,000

4,732,000

Maximum Day

4,198,000

4,481,000

4,894,000

9,144,000

Evaluation of Existing Sources

Available Existing Source (gpd)(3)

 

 

 

 

Westbay Booster (2,400 gpm)(4)

3,456,000

3,456,000

3,456,000

3,456,000

Percival Booster (2,400 gpm)

3,456,000

3,456,000

3,456,000

3,456,000

Allison Well 19 (S11) (900 gpm)

1,296,000

1,296,000

1,296,000

1,296,000

Allison Well 13 (S09) (650 gpm)

936,000

936,000

936,000

936,000

Kaiser Rd. Well 1 (S03) (360 gpm) (5)

518,400

0

0

0

Total Available Source (gpd)

9,662,400

9,144,000

9,144,000

9,144,000

Source Surplus/(Deficiency) (gpd)

5,464,400

4,663,000

4,250,000

0

Table 8.8 Evaluation of Source Adequacy for Zone 380

 

Year

2015

2020

2034

Max(1)

Equivalent Residential Units (ERU's)

4,343

4,663

5,416

20,717

Projected Demand - Gallons per Day (gpd) (2)

Average Day

721,000

774,000

899,000

3,439,000

Maximum Day

1,434,000

1,516,000

1,688,000

6,768,000

Evaluation of Existing Sources

Available Existing Source (gpd)(3)

Westbay Booster (2,400 gpm) (4)

3,456,000

3,456,000

3,456,000

3,456,000

Elliot Booster (2,300 gpm)

3,312,000

3,312,000

3,312,000

3,312,000

Total Available Source (gpd)

6,768,000

6,768,000

6,768,000

6,768,000

Source Surplus/(Deficiency) (gpd)

5,334,000

5,252,000

5,080,000

0

8.3 2015-2020 Source Infrastructure Projects

The source infrastructure projects planned for 2015-2020 will help meet the Drinking Water Utility’s Goal 6:

Infrastructure is prudently financed, and sustainably constructed, maintained and operated to ensure reliable delivery of high quality water to a growing community.

Objective 6A is to design and construct infrastructure to ensure reliable delivery of water. These projects will implement Strategy 6A1: Develop and maintain multiple, geographically dispersed sources of water supply to enhance the reliability of the system. Chapter 9 and chapter 10 describe storage and transmission/distribution infrastructure; Chapter 12 describes operations and maintenance of the infrastructure. Water quality strategies are in Chapter 11.

The City’s Capital Improvement Program includes the following supply source projects, which may be deferred beyond 2020:

•    Briggs Well. Construction of this 1,100 gpm supply well will provide an additional 1.58 Mgd of daily supply capacity for Zones 338 and 417.

•    Olympia Brewery engineering evaluation of possible operational and source development options for the Brewery water source (with Cities of Tumwater and Lacey).

Project level cost estimates are shown in Chapter 13, Table 13.2.