Greater Kaweah GSA Combined RCC & SC Meeting - - PDF document

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Greater Kaweah GSA Combined RCC & SC Meeting

Wednesday, August 7, 2019

www.GreaterKaweahGSA.org

ITEM 2: ANNOUNCEMENTS ITEM 3: MINUTES

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ITEM 4: Summary of Kaweah Coordination

• Draft Coordination Agreement posted to GKGSA website under “Resources”

– still preparing several of its appendices.

• Kaweah GSAs discussing a possible coordinated approach to preparing the

first mandatory annual report to DWR in April 2020.

• Recent meeting with Kaweah Watershed Coalition leadership to discuss GSA

involvement in CV-SALTS implementation.

• TID WaterSMART Grant application to evaluate a water marketing strategy

for the Kaweah Subbasin.

• Draft PSP is out for Prop 68 SGMA funding. Kaweah is eligible for about

$500k in additional planning dollars. There’s only about a 5 week window to prepare an application once the PSP goes final (likely in September) – beginning to work on a scope of work to submit.

Sustainability Goal and Undesirable Results

• Language must be exactly the same amongst the three

subbasin GSPs

• Goal and definitions were developed from the ground up with

input from stakeholders and committees and then reviewed and modified by GSA attorneys

• Mid-Kaweah GSP Public Draft released for comment last week

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Subsidence Sustainable Management Criteria

• Annual Rate*
• Areal Extent*

*That substantially interferes with land uses and may lead to undesirable results.

Subsidence Approach to SMCs

• Subsidence correlates to change in groundwater storage
• Project observed groundwater levels (Fall 2006 to 2016) to 2040

due to maximum withdrawal of groundwater

• Estimate volume of groundwater storage due to maximum

withdrawal – 4,000,000 acre-feet

• Estimate potential subsidence, based on actual subsidence

during 5-year drought

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Subsidence versus Groundwater Storage

Correlation period

Not effected by differences in water years Stable or slight rebound during above-normal water years **

Subsidence during below-normal water years* *

**

87 inches of additional subsidence could result from removal of 4M AF of groundwater storage

Subsidence Minimum Threshold

• Interpolated between

GPS Stations CRCN and P566

87 inches versus 10 inches (2017 to 2040)

• Projected NW and SE to

KDWCD station

• 3.4 inches/year red shading
• 0.5 inches/year blue shading

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Water Quality Trends

• GAMMA database extraction for GKGSA area
• Arsenic
• Nitrate
• Total Dissolved Solids (TDS)

Constituent Time Period # of Results Detects Muni Dom Mon Unk Arsenic, ug/l

1968 – 2019

1,081 63% 91% 4% 2% 3% Nitrate, mg/l as N

1945 – 2019

3,917 96% 88% 1% 2% 9% TDS, mg/l

1945 - 2019

841 100% 67% 5% 3% 26%

Arsenic Trend

Median Values

• Significantly greater sampling during

2000s and 2010s

• Limited data before 2000,

variable results, high reporting limits

• Relatively stable trend 1990s to 2010s
• Percent samples exceeding

primary MCL of 10 ug/l

• 1990s: 31%
• 2000s: 23%
• 2010s: 23%

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Nitrate Trend

Median Values

• Significantly greater sampling during

2000s and 2010s

• Limited data before 1990,

variable results

• Steady increasing trend 1940s to 2010s
• Percent samples exceeding

primary MCL of 10 mg/l as N

• 1990s: 1%
• 2000s: 15%
• 2010s: 28%

TDS Trend

Median Values

• Fair amount of sampling during 1970s

through 1990s

• Significantly greater sampling during

2000s and 2010s

• Slight decreasing trend 1940s to 2010s
• Percent samples exceeding

secondary MCL of 1000 mg/l

• 1990s: 0%
• 2000s: 5%
• 2010s: 11% — Deep groundwater??

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Partial Summary of Projects and Management Actions

• Cross Creek Layoff Basin

– Utilizes roughly 115 acres to store approx. 1,100af of floodwater for later use as well as 350af of in-lieu benefit

• New Recharge Basins for Lakeside Irrigation Water District

– 275 acres of new recharge basins with an average annual benefit of 3,320 af of recharge and 13,600 af of operational storage.

• Delta View Canal in Kings County Water District

– New 100cfs canal and improvement of an existing 120 acre basin for the purposes of groundwater recharge.

• Lakeland Canal Deliveries

– Formalizes an operational diversion from Kings River and Cross Creek and defines the condition under which diversions may occur in order to increase delivery frequency.

Partial Summary of Projects and Management Actions

• KDWCD Hannah Ranch Flood Control Project

– Develops a 1,500af reservoir off of the Kaweah River and FKC.

• Kings River Floodwater Arrangement

– Establishes floodwater agreements on the Kings River for KCWD and LIWD to conduct deliveries and recharge activities within Kings County areas outside of the Kings River place of use.

• Fallowing Program by KCWD and LIWD

– A combined fallowing program which seeks to lease 1,500 acres of agricultural land from willing growers in exchange for compensation

• On-Farm Recharge in LIWD and KCWD

– Targets approximately 500 acres of ag land for over-irrigation and/or flooding during brief periods of high surface water flows.

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Partial Summary of Projects and Management Actions

• GKGSA Land Use Conversion Pilot

– Pilot program to test various land use conversion options to better understand cost / benefit and economic impact to the region.

• Groundwater Extraction / Measurement Program

– Pilot program with other two GSAs to identify most feasible approach to measurement.

• Well Characterization Program

– Video logging and spinner logging of wells to ascertain well construction

• Geophysical Data Survey Project

– Phase II of the SkyTEM work to fill in gaps between Phase I flight lines.

• Domestic Well Assistance Program

– Provides technical assistance and consultation for well repairs, education on RO installations, periodic water quality testing and other assistance.

GSP Public Review Draft

• Board approval of Public Review Draft GSP at a special meeting in late

August or early September

• 90-day notice of public hearing (late November or early December)
• Schedule allows 1+ months to address comments (comments will be

addressed as they come in) followed by adoption and submission to DWR

• DWR is required to establish its own GSP public comment period of no less

than 60 days for an adopted plan

• A GSP that is determined to be incomplete after the deadline may be

revised and resubmitted to DWR within 180 days from the date DWR issues the assessment

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ITEM 6: GKGSA MEETINGS REPORT ITEM 7: COMMUNICATION AND ENGAGEMENT