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EKI TECHNICAL PRESENTATION #19COSUMNES SUBBASIN GSP DEVELOPMENT
15 JULY 2020COSUMNES SUBBASIN WORKING GROUP / TAC MEETING
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Draft – For discussion purposes only
AGENDA ITEM #3 GROUNDWATER SUSTAINABILITY PLAN
TECHNICAL WORK AND PLANNING
¡ Three-month look-ahead (+ Prop 68)
¡ Groundwater Modeling – CoSANA
¡ Prop 68 activities – Field Studies
¡ Monitoring Network Status
¡ Management Areas – Follow up discussion
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GSP - THREE MONTH LOOK AHEAD
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Today
Signed RMW Access Agreements Due Before
11/1/20
Prop 68 Tasks
TM #8: “Water Budget and Preliminary Estimate of Sustainable Yield” - reschedule submission date dependent on completion of model calibration
Well & Land Access
Field Work
CoSANA calibration
TM 10 “Delineation of Management Areas” – reschedule submission date dependent on direction from Working Group
Draft – For discussion purposes only
CoSANA MODEL DEVELOPMENT (1 OF 2)
Cosumnes Subbasin Preliminary Calibration Completed¡ First of a three-step process (see Slide 5).¡ “Child Model” of Cosumnes Subbasin
created from CoSANA.¡ Initial calibration included comparisons
between model-calculated and observed/estimated:- Water levels in 84 wells.
- Vertical gradients between formations at seven locations.
- Horizontal gradients across Subbasinboundaries.
- Surface flows in Cosumnes River and creeks.
- Cosumnes River and creek leakage estimates.
- Analytical water budget.4
Mean Error = -6 feet (low)Basin Foothills = -23 feet (low)Basin Plain = 3 feet (high)
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þ Step 1: EKI completes preliminary calibration of “Child Model” (completed 7/10/20).
q Step 2: W&C integrates Child Model into CoSANA and completes calibration of entire model.
q Step 3: EKI finalizes CoSANA for the Cosumnes Subbasin.
- Integrate new data from Prop 68 as appropriate.
- Evaluate performance and finalize calibration.
Final model employed to support development of TM #8: “Water Budget and Preliminary Estimate of Sustainable Yield.”
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CoSANA MODEL DEVELOPMENT (2 OF 2)
1st of 3-step process completedCosumnes Subbasin Model
(portion of CoSANA Model)
CoSANA Model
Child Model
CoSANA
Draft – For discussion purposes only
PROP 68 SCOPE OF WORK (1 OF 7)
¡ Task 1: Invoicing, Quarterly Reporting, and Grant Administration
¡ Task 2: Project Management
¡ Task 3: Surface Water Advisory Group – CBI/Water Forum
¡ Task 4: Geophysical Investigation – slide 8
¡ Task 5: Isotopic Recharge Characterization Study – slide 9 & 10
¡ Task 6: Groundwater Dependent Ecosystem Verification
¡ Task 7: Voluntary Groundwater Extraction Instrumentation – slide 11
¡ Task 8: Model Refinements
¡ Task 9: Monitoring Well Installation– slide 126
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PROP 68 –WORK FLOW FOR FIELD EFFORTS (2 OF 7)
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Access to wells and field sites
• Isotopic recharge characterization study
• Geophysical investigation
• Install voluntary groundwater extraction instrumentation
Convene Surface Water
Advisory Stakeholder
Group (SWAG)
Design Groundwater Dependent Ecosystem (GDE) field investigation
• Install monitoring wells
• Install water level instrumentation
• GDE field verification
Update CoSANA as appropriate
June 2020 July 2020 Aug – Nov 2020 Dec 2020 – Feb 2021
Site access for GDE verification
Moved to July
Mostly Completed
Moved to Aug
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PROP 68 – GEOPHYSICAL INVESTIGATION (3 OF 7)¡ Geophysical section lines
– Fieldwork will take place over several sessions¡ Sections CR-2 & CR-3 planned for 7/28 & 7/29
– Three (3) optional sites still require access
– SRCD: 3 CR-2 sites scheduled for 7/28 & 7/29
¡ Sections DC-1,-2 and -3 planned for 7/30 & 7/31– Three (3) sites still require access
– Amador County GMA: DC-3 sites
¡ Geophysical field surveys– tTEM contractor recommended expanding
survey area– Survey will be scheduled once access is
confirmed
¡ Tasks to be completed– GSAs to confirm site access to remaining six
sites 8
Potential tTEM Field Expanded tTEM Field
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PROP 68 – ISOTOPIC RECHARGE CHARACTERIZATION STUDY (4 OF 7)
¡ Confirmed access to 22 candidate wells for isotopic sampling – Round 1: Sample pumping wells beginning
week of 7/13
– Round 2: Sample monitoring wells (require additional sampling equipment) mid-August
– Round 3: Sample remaining wells and OHWD TSS well (After installation is completed. Drilling scheduled to begin 7/13)
¡ GSAs will continue to coordinate sampling visits with landowners
9Table of proposed isotope sample sites on next slide
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PROP 68 – ISOTOPIC RECHARGE CHARACTERIZATION STUDY (5 OF 7)
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Sample Site Well ID GSA Sampling
Round1 05N06E30E001M Sac. Co. 1
2 06N06E29K001M Sac. Co. 1
3 06N07E14A001M Clay WD 1
4 06N08E15J001M SRCD 1
5 07N08E06N001M OHWD 1
6 07N08E10K002M SRCD 1
7 07N08E16E001M SRCD 1
8 07N08E36B001M SRCD 3
9 ACGMA Bamert Rd MW DAmador Co.
GMA3
10 ACGMA Bamert Rd MW SAmador Co.
GMA3
11 ACGMA CarbondaleAmador Co.
GMA3
Sample Site Well ID GSA Sampling
Round
12 AWA ARM-5Amador Co.
GMA1
13 City of Galt_Industrial Deep Well 22 City of Galt 1
14 City of Galt_Well 14 City of Galt 1
15 City of Galt_Well 20 City of Galt 1
16 Dillard Elementary_DomWell SRCD 1
17 UC obs_X283687 Sac. Co. 3
18 UC obs_X284220 Sac. Co. 3
19 UC obs_X284227 OHWD 3
20/21/22 OHWD TSS OHWD 3
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PROP 68 – VOLUNTARY GROUNDWATER EXTRACTION INSTRUMENTATION (6 OF 7)¡ Four sites volunteered
– Photos needed for 1 and 2.
– Photos received for 3 and 4.
¡ Two additional sites needed– Ideally wells to supply aquaculture
and/or almonds/walnuts.
¡ Waiting for construction quotes for meter installation.
¡ Site visits by EKI, well contractor and GSA representative proposed for week of 7/13 or later.
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Network ID GSA Well
Use Land Use Access
1 RMW-WQ9/RMW-ISW7
OHWD Irrigation Vineyard –irrigated drip
Verbal
2 -- GID Irrigation Corn/Alfalfa Verbal
3 -- SRCD Ag-Res
Horse Property:
Pasture/Water Trough/Arenas
Verbal
4 -- SRCD Irrigation Ag-residential Verbal
? ? ? Irrigation Aquaculture None
? ? ? Irrigation Almonds/Walnuts
None
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PROP 68 – MONITORING WELL/STREAM GAGE INSTALLATION (7 OF 7)
¡ Stream Gage Locations– Gaging Station 1 – RMG-4/Rooney Dam– Gaging Station 2 – RMG-3/Mahon Dam
¡ Monitoring Well Locations– Well 1
¡ Located near one of the two gaging stations¡ Selection determined primarily by accessibility.
– Well 2¡ Located across Dry Creek from proposed ESJ
monitoring well¡ Replacement for proposed RMW-ISW1
¡ EKI and OHWD / Sac County will finalize proposed locations
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Proposed Stream Gage LocationProposed Monitoring Well Location
Well 1 ?
Well 2
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SGMA MONITORING NETWORK STATUS
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GSA
Number of Wells Number of Gauges
WL Rep. Monitoring
Sites
WLConfirmed Accessible(7/8/20)
WQ Rep. Monitoring
Sites
WQConfirmed Accessible(7/8/20)
ISW Rep. Monitoring
Sites
ISWConfirmed Accessible(7/8/20)
ISW Rep. Monitoring
Sites
ISW Confirmed Accessible(7/8/20)
Amador WA1 6 6 5 4 -- -- -- --
City of Galt 1 1 2 2 -- -- -- --
Clay WD 1 1 -- -- -- -- -- --
Galt ID 2 0 1 0 -- -- -- --
OHWD1 1 1 2 2 2 2 3 0
Sac County 3 3 1* 0 4* 2 1 0
SRCD 6* 2 3* 1 1 1 1 01420 14 9 7 5 5 0
1. Includes TSS sites. * May need replacement wells indicates a count that increased from last meeting
Draft – For discussion purposes only
DISCUSS PUBLIC WATER SYSTEM OUTREACH ¡ Public Water Systems (PWS) are an
important beneficial user of groundwater in the Cosumnes Subbasin
¡ PWS report water quality data to the Safe Drinking Water Information System (SDWIS) website
¡ Integral to Water Quality monitoring network (i.e., these wells are critical parts of the RMS)
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Public Water System Wells
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¡ Domestic well owners are an important beneficial user of groundwater in the Cosumnes Subbasin
¡ When developing Sustainable Management Criteria (SMC) GSAs must consider the “potential effects on the beneficial uses and users of groundwater, on land uses and property interests” (23§CCR 354.26(b)(3))
¡ SRCD & Sacramento County GSAs have begun a more in-depth domestic well survey
¡ Austin Miller from SRCD will discuss his findings and progress
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STATUS OF DOMESTIC PRIVATE WELL SURVEY
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SRCD decision on Management Area designation?
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MANAGEMENT AREAs
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NEXT STEPS
¡ Continue progress on Prop 68 field activities
¡ Update Representative Monitoring Site list as access is confirmed for proposed wells or for alternative wells selected as substitutes for wells determined inaccessible – remains critical path issue for basin
¡ Sustainable Management Criteria analysis delayed until Representative Monitoring Sites are confirmed
¡ Water Budget estimates delayed until CoSANA calibration process is complete
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