Chapter 5 - Source Water Protection

Transcription

Chapter 5 Source Water Protection
Table of Contents
5.1 Overview ....................................................................................................................... 5-1 5.2 Susceptibility Assessment .......................................................................................... 5-1 5.3 Wellhead Protection Areas .......................................................................................... 5-3 5.4 Contaminant Source Inventory ................................................................................... 5-3 5.4.1 Inventory Approach ............................................................................................ 5-3 5.4.2 Data Sources ...................................................................................................... 5-3 5.4.3 Inventory Results ................................................................................................ 5-4 5.4.3.1 Lower Reid Infiltration Gallery............................................................... 5-10 5.4.4 Additional Potential Sources of Contamination ................................................ 5-10 5.5 Notification .................................................................................................................5-11 5.6 Contingency Plan ....................................................................................................... 5-12 5.7 Spill Response ........................................................................................................... 5-13 5.8 Regional ......................................................................................................................5-14 Tables
Table 5-1.
Table 5-2.
Table 5-3.
Table 5-4.
Summary of Water Well Data ............................................................................... 5-2
List of Potential Contaminant Sources (1) .............................................................. 5-5
Potential Source Contamination Notifications ..................................................... 5-12
Emergency Response Plan Emergency Responders ......................................... 5-13
Figures
Figure 5-1.
Figure 5-2.
Inventory of Potential Contaminant Sources ........................................................ 5-8
Inventory of Potential Contaminant Sources (Wells 7, 8, 9) ................................. 5-9
Sammamish Plateau Water and Sewer District
2010 Water Comprehensive Plan
5-i
August 2011
5.
Source Water Protection
Federal and state law requires all Group A public water systems that use groundwater as their
source of supply to develop a wellhead protection program (WHPP). This section provides a
summary of key elements of the District’s WHPP.
5.1
Overview
The District obtains groundwater from two sources: the Plateau and Cascade View production
wells which draw from the Plateau Aquifer System (PAS) and the Lower Issaquah Valley
production wells which draw from the Valley Aquifer System (VAS). The technical portions of the
WHPPs for these sources are presented in two documents: (1) Wellhead Protection Program for
Plateau and Cascade View Wells, Sammamish Plateau Water and Sewer District (AGI
Technologies, 1998), and (2) Lower Issaquah Valley Wellhead Protection Plan, Volumes 1, 2,
and 3 (Golder Associates et al., 1993–1995).
The WHPP must, at a minimum, contain the following seven components, as defined in WAC
246-290, Section 135, Source Water Protection:

A susceptibility assessment including susceptibility forms for each well.

A wellhead protection area (WHPA) delineation for each well within the 1-, 5-, and 10-year
time of travel boundaries marked.

Contaminant source inventory within the WHPA boundaries.

Documentation of purveyor’s notification to all owners/operators of potential sources of
contamination within the WHPA boundaries.

Documentation of purveyor’s notification to regulatory agencies and local governments of
the boundaries of the WHPAs and the findings of the potential sources inventory.

A contingency plan to ensure consumers have an adequate water supply if the principal
source becomes contaminated.

A spill response plan and documentation of coordination with local emergency responders
including police, fire, and health departments. The plan must include WHPA boundaries,
results of a susceptibility assessment, contaminant source inventory findings, and a source
contingency plan.
The following sections summarize the information presented in the two WHPPs, and
supplement or update that material as appropriate to complete the WHPP components.
5.2
Susceptibility Assessment
A susceptibility assessment is required of public drinking water purveyors as the initial step in
the WHPA delineation process. The assessment forms include information on well construction
and production, local aquifer characteristics, and local potential contamination sources.
Susceptibility forms for the wells in the Plateau Zone, Cascade View Zone, and Lower Issaquah
Valley are included in Appendix L. Table 5-1 presents a summary of the pertinent well data
presented in each of the WHPPs (AGI, 1998; Golder Associates, et al., 1993–1995).
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August 2011
Table 5-1.
Summary of Water Well Data
Completion
Mapped Water Level
Well
Name
Wellhead
Elevation
(ft msl)1
Depth
Drilled (ft)
Depth
1R
2
2.2
4R
473.12
417.10
419
350
159
132
180
1207
137 to 147
96 to 116
150 to 175
710 to 845
7
8
9
70
73
75.5
151
190
303
83 to 151
105 to 189
194 to 219
10
423.79
193
135 to 155
173 to 183
11.1
358.11
499
Inglewood
11.2
Channel
Klahanie
15
Cascade View Zone:
Ames Lake
12R
Ames Lake
13R
Ames Lake
14
358.01
884
455
645
665
490
Area
Plateau Zone:
Klahanie
Klahanie
Klahanie
Inglewood
Channel
Issaquah Valley
Issaquah Valley
Issaquah Valley
Klahanie
Inglewood
Channel
Construction
Elevation
(ft msl)1
Depth
(ft)
Elevation
(ft msl)
Mapping
Date
Construction
Date
336 to 326
321 to 301
269 to 244
-360 to
-495
-13 to -81
-32 to -116
-118.5 to 143.5
289 to 268
251 to 241
126
70.64
64.13
217
347.12
346.76
354.87
133
1/95
1/95
1/95
3/2004
3/84
8/68
5/93
3/2004
6
13
16
64
60
59.5
1/95?
1/95?
1/95?
75.64
348.15
409 to 419
426 to 431
461 to -486
-51 to -128
230
-427 to -522
330
785 to 821
839 to 880
225 to 305
245 to 150
145
960
346
135 to 145
810 to 949
305 to 329
510 to 500
-145 to -284
188 to 161
Surface Seal
Thickness
Material2
(ft)
Casing
Depth
(ft)
C
C
B
C
33
20
32
695
137
96
180
695
3/84
8/84
7/91
ND
C+B
C+B
80
80
64
83
105
194
1/95
8/93
C
40
135
128.11
7/93
8/93
C
43
409
232
126.01
8/95
8/93
C
43
785
71
384
7/96
6/96
C
24
225
122.7
516
244.6
522.3
149
245.4
12/99
1/2006
8/90
3/61
1/2006
8/90
ND
C
C
11
810
24.5
Sources: Wellhead Protection Program for Plateau and Cascade View Wells, Sammamish Plateau Water and Sewer District, AGI Technologies, 1998.
Lower Issaquah Valley Wellhead Protection Plan, Volume I, Golder Associates, et al., 1993.
1 Feet above mean sea level using USGS datum
2 Seal Materials: C = cement grout, B = bentonite chips, ND = no further detail on driller’s log
5-2
August 2011
135
810
305
5.3
Wellhead Protection Areas
A WHPA is defined as the surface and subsurface area surrounding a well, wellfield, or spring
supplying a public water supply through which potential contaminants are likely to pass and
reach the wells. In Washington, WHPAs are defined based on the time of travel (TOT) for
groundwater to move from its point of infiltration to its point of discharge at the well. The WHPA
is divided into three primary zones based on 1-, 5-, and 10-year TOT rates. The 10-year TOT
boundary forms the boundary of the WHPA and defines the area to be inventoried and
managed to reduce the risk of potential contamination.
In general, the District has three WHPAs: Cascade View wells, Plateau wells, and Lower
Issaquah Valley wells. WHPA delineations have been developed for each well with the 1-, 5-,
and 10-year TOT boundaries marked. Figures 5-1 and 5-2 present the boundaries for each of
the wells within the three WHPAs.
In recent years, the District has reviewed its WHPA boundaries. The District’s sophisticated
three-dimensional finite element groundwater model was used to review the earlier results of the
WHPA delineation for the Plateau wells, which was originally developed using analytical
methods. Appendix M provides a summary of this analysis. Because the finite element
groundwater flow model has been calibrated to transient conditions and incorporates vertical
groundwater flow and monthly pumping and groundwater recharge variations, the modelsimulated WHPAs are likely more representative of well contributing areas than WHPAs
estimated using analytical methods. However, the delineated area using the finite element
model is smaller than that resulting from analytical methods. Therefore, in order to provide
conservative protection of groundwater resources, the District will continue to utilize the larger
contributing recharge areas, delineated by the analytical WHPA delineation method.
5.4
Contaminant Source Inventory
5.4.1
Inventory Approach
The District draws groundwater from general well field areas designated as Cascade View, the
Sammamish Plateau, and the Lower Issaquah Valley. The wells that are currently active in
these areas are:
1) Cascade View wells 12R, 13R, and 14.
2) Sammamish Plateau wells 1, 2.1 & 2.2, 4R, 10, 11.1, 11.2, and 15.
3) Lower Issaquah Valley wells 7, 8, and 9.
The locations of these wells are shown on Figures 5-1 and 5-2.
The inventory of potential contaminant sources within the WHPAs involved a search of the
Washington State Department of Ecology’s Facility/Site Identification System (F/SID) database
and field reconnaissance.
5.4.2
Data Sources
The F/SID database is an internet-based system (accessed via the following website:
http://www.ecy.wa.gov/fs/) and contains a compilation of potential contaminant site information
5-3
August 2011
identified under the following categories: State Cleanup Sites, Federal Superfund Sites,
Hazardous Waste Generators, Solid Waste Facilities, Underground Storage Tanks, Dairies, and
Enforcement. The use of this comprehensive source of information is a standard approach
accepted by DOH to facilitate updates to potential contaminant source inventories.
A GIS analysis was performed wherein potential contaminant sites noted in the F/SID database
to be located within a District WHPA were geo-referenced and mapped (see Figures 5-1 and 52). The spatial integrity of these locations was then verified first by using Google Earth to
confirm that land uses and structures in the vicinity of the F/SID site locations were consistent
with the noted site activities. This resulted in fine-tuning of the mapping, as some facility
addresses identified in the F/SID were inaccurate.
Further “ground-truthing” of site locations was achieved through a windshield survey conducted
by District staff in the fall of 2009. This resulted in further revision to the list and mapping of
potential contaminant source sites, as the activities and/or structures at some noted locations
did not match the activities identified in the F/SID.
Also noted in the survey were injection well locations identified in Ecology’s Underground
Injection Control (UIC) program database, as of June 2010. These sites represent injection
wells, most of which serve the purpose of managing stormwater flows by returning water to the
ground.
In addition to the information gained from the above activities, the extent of sewer service
provision throughout the District WHPAs was mapped, based upon information contained in the
District’s GIS and data provided by the City of Issaquah.
5.4.3
Inventory Results
Table 5-2 provides a listing of potential groundwater contaminant sites located within District
WHPAs, based upon the review of data sources described above, along with summary
information for each site. Additional information for those sites identified in the F/SID is
available by querying the F/SID website. The sites listed in Table 5-2 are depicted in Figures 51 and 5-2.
In total, 91 sites were identified as having characteristics reflective of potential groundwater
contamination. Most (81) of the sites are located within the heavily developed areas comprising
the WHPAs of District Wells 7, 8, and 9. The remaining 10 sites (Site N0s. 70-79 in Table 5-2)
are located within the WHPAs of other District wells.
Of the 81 sites located in the Lower Issaquah Valley, 28 are located within the 10-year time-oftravel zone of Wells 7, 8, and 9, while 37 are located within the 5-year time-of-travel zone of
these wells. The remaining 16 sites are located in the 1-year time-of-travel zone.
These sites were compared to those listed in Appendix R of the 2001 Plan (i.e., the previous
comprehensive contaminant source inventory). A number of sites did not appear in the previous
plan, and a number of sites in the previous plan did not appear in this current search. Over the
past decade, new sites have been added to the F/SID and some have been removed due to risk
of contamination having been mitigated, which can explain the differences between the two
database searches. In addition, the F/SID had not been compiled in 2001, and the previous
search was conducted through multiple databases (which have since been combined) to obtain
the information for the report.
5-4
August 2011
Table 5-2.
Site
Id(2)
1
2
3
4
5
6
7
8
9
10
11
List of Potential Contaminant Sources (1)
Facility Name
Cougar Mountain Veterinary Hospital
Issaquah School Dist 411 Transp Ctr
(Bus Garage)
Issaquah High School
Issaquah School Dist Clark Elem
Issaquah Sportsmen Club 2
Issaquah Middle School (and Swimming
Pool)
Issaquah City Food Clothing
Issaquah Furniture Inc
Cat Clinic of Issaquah
Front Street Red Apple Market
Ben Franklin Issaquah
WA DFW Issaquah Hatchery
12
13
14
15
16
17
Issaquah Cleaners
Issaquah Old Police Station
Issaquah City Sunset (Fire Station)
Number Not Used in Figures
Shell Station 120677/117
18
19
20
21
22
23
Issaquah Brewhouse
NAPA Auto Parts Issaquah
Las Margaritas
Dominoes Pizza
Stephanie A Kavanaugh DMD MSD
Issaquah Feed and Service
24
25
26
27
28
29
30
31
32
Arnold R Sims DDS
Douglas L Perkins DDS
Number Not Used
Busch Collision Inc (Precision)
Number Not Used
Toyo Matsumoto DDS
Microsoft Highlands SW Detention
Pond
Glen Yorita DDS
Well(s)
7,8.9
7,8.9
WHPA
Time-ofTravel
Zone
10
10
7,8,9
7,8,9
10
10
7,8,9
7,8,9
10
10
Hazardous Waste Generator
Source Control Inspection
Emergency/Haz Chem Rpt TIER2,
Non Enforcement Final, 401CZM
Project Site
Underground storage tank, LUST
facility
Underground Storage Tank
7,8,9
7,8,9
7,8,9
7,8,9
7,8,9
7,8,9
10
10
10
10
10
10
7,8,9
7,8,9
10
10
7,8,9
10
Hazardous Waste Generator, LUST
facility, Haz Waste Management
Activity, Hazardous Waste
Generator, Source Control
Inspection
Voluntary Cleanup Sites,
Underground Storage Tank, LUST
Facility
7,8,9
10
7,8,9
7,8,9
7,8,9
7,8,9
7,8,9
7,8,9
10
10
10
10
10
10
7,8,9
7,8,9
10
10
7,8,9
5
7,8,9
7,8,9
10
1
7,8,9
5
Type
Facility, Underground Storage
Tank
Hazardous Waste Generator,
State Cleanup Site
Dam Site
5-5
August 2011
Site
Id(2)
33
Facility Name
Issaquah City Facilities
34
Darigold Issaquah (Westfarm Foods)
35
36
37
38
39
40
41
42
King County DOT DPW Issaquah Pit
Boehm's Candies Inc
Gilman Autobody
Ride Motor Sports Inc
Eastside Pediatric Dental Group
Rosemary Warren DDS
Grange Supply Inc
43
Issaquah City PW Operations
44
45
46
47
Number Not Used
Port Blakely Communities
Issaquah Highlands Lower Reid
Infiltration
Chevron 95399
48
Lakeside Sand and Gravel
49
50
51
52
53
54
55
56
57
58
59
Caseys Shell
Big O Tires Gilman Blvd
Issaquah Veterinary Hospital
Shell 119
Marks Japanese & European Auto
Ultimate Detail
Issaquah Auto Tech Ltd
Werner Services
Microsoft Communications Sammamish
Dirks Fine Drycleaning
60
61
62
63
64
65
66
67
68
69
Natural Dental Assoc
Banglalore Cuisine of India
The Boarding House
Number Not Used
Julia's of Issaquah Inc
Barry Feder DDS PS
Sammamish Plateau WS Dist Well 9
Well(s)
7,8,9
WHPA
Time-ofTravel
Zone
5
7,8,9
5
LUST Facility
Facility
Haz Waste Management Activity,
7,8,9
7,8,9
7,8,9
7,8,9
7,8,9
7,8,9
7,8,9
1
1
1
1
1
1
1
7,8,9
1
General Permit Industrial
7,8,9
7,8,9
1
1
Voluntary Cleanup Sites, LUST
Facility, Emergency/Haz Chem
Rpt TIER2
Noted During Windshield Survey
(USTs likely as gas and diesel
pumps are present)
7,8,9
5
7,8,9
1
Emergency/Haz Chem Rpt TIER2
Voluntary Cleanup Sites
7,8,9
7,8,9
7,8,9
7,8,9
7,8,9
7,8,9
7,8,9
7,8,9
7,8,9
7,8,9
5
5
5
1
5
5
5
6
5
5
7,8,9
7,8,9
7,8,9
5
5
5
7,8,9
7,8,9
7,8,9
5
5
1
Type
Hazardous Waste Planner, Haz
Waste Management Activity
Hazardous Waste Planner, LUST
Facility, Minor Industrial
Enforcement Final
5-6
August 2011
Site
Id(2)
70
71
Facility Name
Sammamish Plateau Water & Sewer
Dist Well
Klahanie Shopping Center
72
Sammamish Highlands Shopping Center
73
Sammamish Plateau Water & Sewer
Dist 50T
Ecology UIC Program Well
Type
(Gas station, dry cleaners,
veterinary hospital, and dentist
office present)
(Oil Can Henry, paint store,
veterinary clinic, and Red Carpet
Cleaners present)
74
Drinking water well
75
Drinking water well
76
No description in UIC database
77
Drinking water well
78
79
80
81
82
83
84
85
86
87
88
89
90
91
Notes:
(1) Sources of data:
Washington State Department of Ecology F/SID Database (May 2010).
Washington State Department of Ecology UIC Database (June 2010).
District windshield survey (2009).
(2) See Figures 5-1 and 5-2 for site locations. Sammamish Plateau Water and Sewer District
Well(s)
11.1, 11.2
WHPA
Time-ofTravel
Zone
5
10, 2.2
1
4R,11
10
12R
5
12R
4R, 11
4R
1
2.1,2.2
15
7,8,9,
7,8,9,
7,8,9,
7,8,9,
7,8,9,
7,8,9,
7,8,9,
7,8,9,
7,8,9,
7,8,9,
7,8,9,
7,8,9
10
5
5
1
1
1
1
1
5
10
5
5
5
5
5
5
10
10
5-7
August 2011
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FIGURE 5-1
Sammamish Plateau Water and Sewer District | Water Comprehensive Plan
Sammamish Plateau
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Freeways
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Minor Roads
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Current Water Service District Boundary
King County UGA Boundary
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Inventory of Potential Contaminant Sources (Wells 7, 8, 9)
FIGURE 5-2
Sammamish Plateau Water and Sewer District | Water Comprehensive Plan
5.4.3.1
Lower Reid Infiltration Gallery
One notable potential contaminant site listed in Table 5-2 (Site No. 46) is the Issaquah
Highlands Lower Reid Infiltration Gallery (LRIG). In 2006, the District began evaluating the
potential for ground water impacts from this large stormwater facility that at the time was directly
injecting stormwater runoff from an urban area (Issaquah Highlands) being developed in the
City of Issaquah. Issaquah Highlands (originally called Grand Ridge) is a 2,300-acre
development that typically generates at least 1,400 acre-feet of stormwater annually.
After failure of several on-site stormwater disposal systems, the owners (developer and City)
expanded one of the few working infiltration facilities known as the LRIG. With seasonal
measured discharges of over 8 cubic feet per second, the LRIG is among the largest ground
water infiltration structures ever constructed in Western Washington and there was virtually no
monitoring being conducted for the presence of water quality contaminants commonly found in
stormwater runoff. The District recognized that direct discharge of such quantities of stormwater
could seriously impair the high-quality groundwater supply the Lower Issaquah Valley Aquifer
(LIVA) provides. The LIVA has been a major source of public water supply for the District for
several decades and provides water for several other municipal water systems in the valley.
The potential impacts of this discharge are particularly ominous for the District because it owns
and operates Well 9, located 600 feet west of and immediately downgradient from the LRIG.
Well 9 is one of three production wells the District maintains in the LIVA to provide water service
to over 50,000 residents within its service area.
To evaluate the potential impacts of injecting stormwater into the aquifer, the District began
independent water quality sampling, and water level monitoring in 2006. In 2008, the District
presented these data and related findings in a comprehensive report (Evaluation of the Lower
Reid Infiltration Gallery, CDM, June 13, 2008). The report examines the existing stormwater
collection system, controls, and pre-disposal treatment required under the Ecology Phase II
Municipal Stormwater Permit. The report also described prior operations and the areas of the
LRIG’s non-compliance with the State of Washington Ground Water Quality Non-Endangerment
Standard.
Over the several years of technical review and District input, Ecology has twice been prompted
to prepare enforcement orders to the owners to curtail all discharge through the LRIG until
results from additional monitoring wells can be reviewed and indicate no potential for
groundwater degradation from injection through the LRIG.
By the end of 2009, the City had installed two new monitoring wells and signed an agreed order
with Ecology to monitor background water quality in the monitoring wells and stormwater. The
order also requires the City to divert all stormwater directly to North Fork Issaquah Creek during
this period of investigation. At the conclusion of the two- year monitoring period (summer of
2011), the City is required to prepare an evaluation of the results for Ecology’s review and
determination regarding the suitability of injecting upland stormwater in the LIVA at the LRIG.
5.4.4
Additional Potential Sources of Contamination
In addition to the point sources identified in 5.4.3, non-point sources within the WHPAs can also
be a potential source of contamination. Such sources include roadway runoff and septic system
discharges.
5-10
August 2011
Figures 5-1 and 5-2 depict the roadways and highways that are within or near the District’s
WHPAs. Potential contamination from roadways includes pollutants transported by runoff to
areas where surface water infiltrates into groundwater, as well as impacts from spills that occur
due to accidents or improper material transport.
The figures also identify those portions of the WHPAs that are currently not provided sewer
service, and which therefore contain active septic systems. In Cascade View, sewer service is
not provided in any of the WHPAs. This, coupled with the few identified point sources of
potential contamination and the more rural nature of the area, results in septic system
discharges posing the greatest risk of potential contamination to area groundwater.
Sewer service is provided to approximately half of the extent of the WHPAs for the Sammamish
Plateau wells, and nearly all of the WHPA for the Lower Issaquah Valley wells.
5.5
Notification
It is required that all owners/operators of potential sources of contamination within the WHPA
boundaries, as well as regulating agencies and local governments, be notified of the WHPA
boundaries, inventory findings, and contingency plan conclusions. The District has completed
the initial notification. Applicable emergency responders have also been notified so that they
can incorporate the WHPA into their spill response planning activities. Table 5-3 lists the
businesses and agencies that have been notified.
5-11
August 2011
Table 5-3.
Potential Source Contamination Notifications
Agencies and Emergency Responders
Washington State Highway Patrol
Washington State Military Department Emergency
Management Division
City of Sammamish Police
King County Emergency Management Division
Fall City Fire Department (KCFD 27)
Department of Ecology Spill Response NW Section
Redmond Fire Department (KCFD 34)
Washington State Department of Public Health – NW
Regional Office
King County Sheriff Office
Eastside Hazardous Materials Team
Businesses
Union 76 (Old BP Service Station 11059)
Darigold
Plateau Shell
Grange Supply Inc
Video Update (former Exxon #7 6107)
Former Vehicle Repair Shop
Red Carpet Drycleaners
Gilman Autobody
Safeway
Issaquah City Public Works Department
Inglewood Shopping Center
James M Perry
Bartells 29
Lighthouse Properties
QFC
Browes & Barter Liquidation Sales (Previously Issaquah
Feed & Service)
Klahanie Cleaners
Napa Auto Parts
Klahanie Texaco
Mobil #1 D6R
Bake's Marine Center
Washington State Fish & Wildlife
Gilman Autobody & Eastside Equipment
Texaco 632320280
Lonnie's Lawnmower Repairs
Mobil #10 D6R
Schucks Auto Supply
Issaquah Cleaners
Lakeside Industries
Front Street Red Apple Market
Cadman Inc, Western Asphalt Inc
La Vaug Ward
Western Asphalt Inc
Issaquah City Food & Clothing
Dirks Fine Drycleaning
Gilman Thompson
Gramore Development (Precision Tune)
Issaquah Middle School
Big O Tires
The Best Little Dry Cleaner
Texaco Station #63-232-1468
Issaquah School District Clark Elementary
Harold J Ruby ARCO 4466
Issaquah School District 411 Transportation
Issaquah Auto Tech
Issaquah High School
Casey's Shell On Gilman
Issaquah Old Police Station
Chevron SS 95399
Eastlake High School
Eastside Truck & Car Rental
Oil Can Henry’s
Issaquah School District 411
Issaquah School District Valley Elementary
City of Issaquah Public Works Department
Issaquah Veterinary Hospital
Other Residential Homes
Ruby's Towing
Eastside Fire and Rescue
City of Issaquah Police
5.6
Contingency Plan
The District has developed a contingency plan that prioritizes the measures to be taken if a well
or wellfield source is disrupted. The contingency plan is divided into short-term and long-term
components listed below.
5-12
August 2011
Short-Term Components. If there is a short-term water disruption to the water supply, the
District will restrict water use to 80 percent of the average wintertime water use and attempt to
locate alternative water sources to meet this reduced demand:
1. Should a well fail to meet water quality or quantity requirements and the problem appears to
be more than temporary, then the District’s first line of action will be to apply to Ecology for
an emergency transfer of water rights while the source of the problem is investigated.
2. The District’s Regional Supply Connections would be the primary means by which water lost
due to a well supply disruption would be replaced.
3. Existing interties will also be utilized as available to meet short-term reduced water demands
upon the concurrence of the supply purveyor. This measure would potentially work with
Union Hill Water Association in the Cascade View Zone, and with Northeast Sammamish
Sewer and Water District and City of Issaquah in the Plateau Zone. The amount of water
available to be conveyed through these existing interties is limited; their use would depend
on the volume of water required to meet demands.
4. The District will take measures to develop additional interties to be used as contingency
measures. Potential future interties that would meet these criteria could be with the City of
Redmond, via the Redmond Ridge development for the Cascade View Zone, and the City of
Issaquah via the Issaquah Highlands development, for the Plateau Zone.
Long-Term Components. If there is a long-term water disruption to the District’s groundwater
supply, the District will consider the potential for redeveloping the disrupted groundwater source,
permanent transfer of the water rights from the disrupted source to an unaffected groundwater
source, or more fully utilize the Regional Supply Connections.
5.7
Spill Response
The District has completed a spill response plan that specifies the emergency responders to be
contacted if a contaminated spill occurs within the identified WHPAs. Table 5-4 lists each of the
responders that could potentially be involved in a spill event. The complete Spill Response Plan
is included in Appendix N.
Table 5-4.
Emergency Response Plan Emergency Responders
Agency
Eastside Fire and Rescue
City of Issaquah Police
City of Sammamish Police
Fall City Fire Department (KCFD 27)
Redmond Fire Department (KCFD 34)
Eastside Hazardous Materials Team (Bellevue 911 Dispatch)
King County Sheriff Office
Washington State Highway Patrol
Washington Military Department Emergency Management Division
King County Emergency Management Division
Department of Ecology Spill Response NW Section
Washington State Department of Public Health – NW Regional Office
Telephone Number
(425) 313-3700
(425) 837-3200
(425) 295-0770
(425) 222-5841
(425) 556-2200
(425) 577-5656
(206) 296-3311
(425) 401-7788
(800) 258-5990
(206) 296-3830
(425) 649-7000
(253) 395-6750
1-877-481-4901 after hours
5-13
August 2011
5.8
Regional
The District has been working with adjacent purveyors and entities to coordinate aquifer
management activities. The District shares aquifers with the City of Issaquah, Northeast
Sammamish Sewer and Water District, and Union Hill Water Association. In addition, the Cities
of Issaquah and Sammamish, and King County have land use jurisdiction within the District’s
aquifer recharge areas.
The District played an active role in the development of the Issaquah Creek Valley Groundwater
Management Plan that was finalized in March 1999. The purpose of the Issaquah Creek Valley
groundwater management committee is to define and implement the aquifer protection
strategies presented in the Groundwater Management Plan.
Because Wells 7, 8, and 9 are located in the same aquifer as the City of Issaquah’s wells, the
District has met periodically with City of Issaquah representatives to discuss issues associated
with co-management of the aquifer.
The District meets regularly with the Northeast Sammamish Sewer and Water District through a
joint facilities committee because the two utilities share facilities (reservoir) and the aquifer. The
District’s Cascade View Zone is located adjacent to Union Hill Water Association, and it is
believed that the two utilities pump from the same aquifer system. The District communicates
regularly with Union Hill on issues related to provision of water service in this area.
The District’s primary regional strategy is to work with the entities that have land use control
within its WHPAs to develop protection measures. For example, the City of Sammamish added
a Critical Aquifer Recharge Area (CARA) to its Critical Area Ordinance, which includes the
District’s WHPAs. The City of Issaquah has also included District WHPAs in the City’s CARA
maps.
The District is also interested in protecting the groundwater recharge areas for each of the
wellfields. Future groundwater efforts will include defining the groundwater recharge boundaries
and working with agencies to protect those areas.
5-14
August 2011

Chapter 5 - Source Water Protection

Transcription

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