GSP Development Status Kaweah Subbasin Coordination Numerical Model - - PDF document

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Greater Kaweah GSA Technical Advisory Committee Meeting

Kaweah Delta Water Conservation District 2975 N. Farmersville Blvd. - Farmersville CA

Tuesday, October 2, 2018

GSP Development Status

• Kaweah Subbasin Coordination

– Numerical Model – Data Management System – Subbasin Hydrogeologic Zones – Basin Setting

• Greater Kaweah GSP

– GSP Document and Mapping Development

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GSP Development Schedule

Month

4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 4A-1 Data Management System 4A-2 Basin Setting 4A-2a Water Supply Accounting 4A-3 Numerical Modeling (Development & Sub-Basin Level Analysis) 4A-4a Sustainability Goal and Undesirable Results 4A-4b Monitoring Networks 4A-4c Minimum Thresholds, Measurable Objectives, and Interim Milestones 4A-4d Projects, Management Actions, and Adaptive Management 4A-5 Outreach 4D-1 Data Management System (Maintenance) 4D-2 Numerical Modeling (GSA Specific Runs & Data Management) 4D-3a Introduction 4D-3b Basin Setting 4D-3c Sustainability Goals and Undesirable Results 4D-3d Monitoring Networks 4D-3e Minimum Thresholds, Measurable Objectives, and Interim Milestones 4D-3f Water Supply Accounting 4D-3g Projects, Management Actions, and Adaptive Management 4D-3h GSP Reporting 4D-4 Outreach within GSA Area GSA Task Sub-Basin Task Overlap with Sub-Basin Task Overlap with GSA Task Task Number

Year

2017 2018 2019 Completion Date 1/30/2020

Kaweah Sub-Basin Coordination Effort Great Kaweah GSA Effort

2020

GSP Content Projects and Management Actions Groundwater Model Simulations

Sep Oct Nov Dec Jan 2019 Feb

2018 SUBBASIN ACTIVITIES

Complete Groundwater Model Update Complete Basin Setting/Water Budget SMC Goal and SI Assessment Complete Intro and Basin Setting/Water Budget

GSP Development Schedule (6-Month Look Ahead)

Groundwater Model Simulations SMC Thresholds and Objectives – Iterative Process Developed by Stakeholders Informed by technical information including groundwater modeling

GSA Deliverable

Define Management Areas Develop Thresholds and Objectives for MAs Water Level Projections Draft Monitoring Network Chapter

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Numerical Model

• Phase 1: KDWCD MODFLOW model review is complete.

– Model Assessment TM reviewed by the TAC and comments provided to GEI. – GEI is now in the process of addressing those comments.

• Phase 2: Expand the model spatially and temporarily

– Model grid has been expanded and refined to 500 ft x 500 ft – Groundwater Elevation database for calibration targets has been completed – Boundary Conditions have been spatially located and are being populated – Davids Engineering data has been processed for input into the model.

• Modeling team is working to develop GW pumping by area.

– Estimated Completion Date for Draft Calibrated Model: November 2018

• Phase 3: GSA specific model runs

– Late 2018/Early 2019

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Numerical Model

INSERT FIGURE FROM BRENT.

Surface Water Deliveries were Subtracted from Crop Demand

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Surface Water Deliveries were Subtracted from Crop Demand

Data Management System

• Data formatting that has been completed and uploaded:

– Well Construction

• From Tulare Co. database

– Lithology – Water Quality

• Ongoing Data Formatting:

– Remaining Water Quality – Remaining Well Construction – Remaining Lithology

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Subbasin Hydrogeologic Zones

• The Management Team Technical Working Group has

been meeting to discuss the Subbasin wide definitions of Undesirable Results and how to establish Management Areas with Subbasin-wide Hydrogeologic Zones (HZs).

– Undesirable Results definitions will be presented at the Subbasin Management Team meeting, and discussed at each GSA’s respective TAC for recommendations. – Hydrogeologic Zones were shown at the Subbasin Management Team meeting on 9/19/18.

Proposed Hydrogeologic Zones

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Proposed Hydrogeologic Zones Cross Section Index HZ 4 HZ 10 HZ 8 HZ 7 HZ 3 HZ 4 HZ 2

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HZ 1 HZ 7 HZ 6 HZ 4 HZ 2 HZ 4 HZ 2

SMCs – Next Steps

• Once Undesirable Results definitions are finalized, the

TACs will review data for each Management Area to set Sustainable Management Criteria (SMCs) in coordination with the other GSAs.

– Minimum Thresholds, Measurable Objectives, and Interim Milestones will be coordinated, depending on the Management Area’s location with respect to the other GSA(s). – REMINDER: The GSAs still maintain control over projects and management actions necessary to meet the Measurable Objectives in their respective management areas.

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SMCs – Next Steps

• As a starting point for Minimum Thresholds, GEI is

working to develop GW level trends based on hydrographs for each HZ during the ten worst years of hydrology (2006 – 2016).

– This is to identify a GWL to avoid for each Representative Monitoring Site within a given Management Area.

• Measurable Objectives (i.e. the target GWL for each

Monitoring Site) will be set to meet the Sustainability Goals for each GSA, which are coordinated with the Goal for the Subbasin.

Subbasin Level Basin Setting

• Subbasin Level Basin Setting report sent to the GSA

managers on 9/24/18. The report includes:

– Hydrogeologic Conceptual Model (HCM) narrative and figures – Subbasin Water Budget and Water Budget for each GSA – Characterization of Water Quality – Description of Historical and Current Subsidence

• GSA Managers to provide their comments by 10/15/18.
• Comments received from GKGSA TAC to also be

addressed in revision of figures for Basin Setting report.

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Subbasin Level Basin Setting - HCM

• In addition to a narrative description of the hydrogeology
• f the Subbasin, the following figures were provided:

– Groundwater Contours for key years – Hydrographs for Key Wells throughout the Subbasin – Map of hydraulic parameters

Spring 1981 Groundwater Contours

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Spring 1999 Groundwater Contours Spring 2011 Groundwater Contours

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Spring 2015 Groundwater Contours

Hydrographs

Criteria for Selecting Key Wells:

• Long Period of Record
• Known Completion
• Representative of GW Levels in the Area

A total of 1300 hydrographs have been created for the entire Subbasin and are available for inclusion in the GSPs for each GSA.

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Key Well Locations Select Key Well Hydrographs

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Vertical Gradients Map (Based on Paired Monitoring Wells) Vertical Gradients Map (Based on Paired Monitoring Wells)

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Distribution of Hydraulic Parameters

Water Budget

• Components have been Identified for Inflow and Outflow.
• Framework for Sub-Basin and GSA-Level Water Budgets

developed.

• Davids Engineering ET Data through 2017 has been included in

current iteration of Water Budget.

– Subsurface Flow conditions being developed for years 2013 through 2017 for the Sub-Basin.

• The Water Budgets themselves are PRELIMINARY and being

further refined with data received after they were done.

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Greater Kaweah GSA Water Budget Summary Annual Ag Pumping Water Year 1999

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Annual Ag Pumping Water Year 2016 Annual Surface Water Delivery Water Year 1999

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Annual Surface Water Delivery Water Year 2016

Subbasin Water Quality

• 47 Public Water Systems were identified and analyzed within the

Subbasin.

• Total of 174 public water system wells evaluated.
• Water quality data was available in State Drinking Water

Information System (SDWIS) database.

• GeoTracker and EnviroStor Databases were used to identify

contaminant plumes/sites.

• State Water Resources Control Board (SWRCB)’s Human Right to

Water Portal was used to identify contaminants commonly violating drinking water standards.

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Public Well Locations

Constituents Analyzed

• Arsenic
• Nitrate
• Tetrachloroethylene (PCE)
• Dibromochloropropane (DBCP)
• 1,2,3-trichloropropane (TCP)
• Sodium
• Chloride
• Hexavalent Chromium

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Observed Arsenic Trends

• Wells with high arsenic levels tend to be on the western

portion of the Subbasin where the Corcoran clay is present.

• Wells generally deeper than 250 ft have arsenic concentrations

greater than 5 ppb.

• pH levels greater than 9 units were observed in wells with

arsenic levels greater than 10 ppb.

• pH ranges from 7.0 – 8.6 units were observed in wells with

arsenic levels less than 5 ppb.

Arsenic Wells Concentration > 5 ppb

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Arsenic Levels vs. Total Well Depth

2 4 6 8 10 12 14 6/12/2008 9/24/2008 6/18/2009 9/16/2009 12/16/2009 6/2/2010 9/15/2010 12/16/2010 9/20/2011 12/12/2011 1/18/2012 3/21/2012 6/19/2012 8/17/2012 9/13/2012 12/6/2012 3/20/2013 6/18/2013 8/14/2013 9/19/2013 11/8/2013 12/12/2013 3/19/2014 8/28/2014 12/10/2014 6/26/2015 9/17/2015 12/15/2015 3/15/2016 4/5/2016 5/3/2016 6/24/2016 7/11/2016 8/25/2016 9/15/2016 11/21/2016 1/12/2017 3/9/2017 5/18/2017 6/8/2017 7/20/2017 8/24/2017 9/7/2017 9/21/2017 10/19/2017 11/9/2017 12/21/2017 1/18/2018 2/8/2018 3/8/2018 4/19/2018 5/24/2018 6/7/2018 Arsenic (ppb) Sample Date

Hydrogeologic Zone 2 - Arsenic Levels vs. Total Depth of Well

Well A (284') Well B (760') Arsenic MCL

Observed Nitrate Trends

• The eastern portion of Subbasin tends to have wells with

nitrate concentrations greater than 5 ppm or increasing trends.

• Other studies have correlated orchard and vineyard land uses

with elevated nitrate concentrations, which is in the eastern portion.

• USGS report correlated medium to high density septic systems,

also located in the eastern portion.

• Shallow wells less than 250 ft deep or with sanitary seals less

than 250 ft had higher nitrate concentrations.

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Nitrate Wells Concentration > 5 ppm

Nitrate Levels vs. Sanitary Seal Depth

R² = 0.3656 R² = 0.4769 R² = 0.1133 2 4 6 8 10 12 14 16 18 20 Nitrate as N (ppm) Sample Date

Hydrogeologic Zone 4 - Nitrate

Well A (280') Well B (260') Well C (370') Nitrate MCL Linear (Well A (280')) Linear (Well B (260')) Linear (Well C (370'))

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Evaluation of Septic Tank Density, Relative to Public Water System Wells with High Nitrate

Observed TCP Trends

• Majority of TCP detections located in the central portion of the

Subbasin.

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Wells with Historical TCP Detections

Contamination Plumes/Sites

• There is a city-wide PCE investigation in Visalia that involves 9

sites.

• Total of 21 contamination sites identified between SWRCB –

GeoTracker database and DTSC – EnviroStor database.

• 16 sites should be monitored to determine the extent of

impact to groundwater.

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Contamination Site Locations in Relation to Wells with PCE and DBCP Detections

Observed Sodium and Chloride Trends

• Not a major constituent of concern in the Subbasin.
• Elevated sodium and chloride wells located in small pockets.

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Locations of Elevated Sodium & Chloride Wells

Increasing Chloride Levels in Wells

R² = 1 R² = 0.8862 100 200 300 400 500 600 700 5/9/2002 9/28/2006 7/22/2009 7/16/2013 Chloride (ppm) Sample Date

Hydrogeologic Zone 8 - Chloride

Well 1 Well 2 Chloride Ag Goal Chloride SMCL Linear (Well 1) Linear (Well 2)

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Increasing Chloride Levels in Wells

R² = 0.9416 R² = 0.4675 100 200 300 400 500 600 700 800 900 1000 9/18/2002 8/9/2005 8/18/2008 9/15/2008 5/13/2009 8/9/2011 8/16/2011 12/13/2011 8/21/2012 8/12/2014 8/25/2015 8/8/2017 5/22/2018 Chloride (ppm) Sample Date

Hydrogeologic Zone 7/9 - Chloride

Well A Well B Chloride Ag Goal Chloride SMCL Linear (Well A) Linear (Well B)

Subbasin Subsidence

• Both historical and current subsidence data show that it occurs

at its greatest magnitude in the southwest portion of the Subbasin.

• Subsidence that has the potential to affect the Kaweah

Subbasin also occurs in the neighboring Subbasins.

– Further coordination between the Kaweah, Tule, and Tulare Lake Subbasins to address subsidence as an Undesirable Result, especially with respect to protection of critical infrastructure.

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Subbasin Subsidence

• A comparison of historic subsidence and subsurface

compaction data and DWR water year indices shows that:

– Greater rates of subsidence correspond with below normal water year indices, and – Years with lower subsidence rates correspond with higher than normal water year indices.

Historical Subsidence 1926 to 1970

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Rate of Subsidence for January 2007 to March 2011 Rate of Subsidence for January 2015 to March 2017

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Regional Subsidence – Spring 2015 through Spring 2017

GSP Development

• Introduction Chapter

– GEI received comments from TAC and other Committees on 9/20/18 – Revisions to address these comments are currently underway

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GSP Development

• Basin Setting Chapter

– Will be mostly based upon the Subbasin Level Basin Setting report – The narrative will highlight conditions and features specific to GKGSA – Completion of the Draft GKGSA Basin Setting Chapter by mid- October, 2018

• Due to the timing of comments, this preliminary draft will not include

comments from the GSA Managers’ review of the Subbasin-wide Basin Setting report.

GSP Development

• Monitoring Network Chapter

– Consists of 3 parts:

• A description of existing monitoring programs and the data collected
• Identification of data gaps with respect to the requirements of SGMA
• Plans to address the data gaps identified in the 2020 GSP

– The first two parts of the Draft GKGSA Monitoring Network Chapter under internal review. Estimated date of delivery to GKGSA TAC is 10/19/18.

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Overview of Existing Monitoring

The following have been identified at the Subbasin level:

• Existing groundwater level monitoring programs
• Existing groundwater quality programs
• Existing land surface subsidence monitoring, and
• Existing surface water flow monitoring

Existing Groundwater Level Monitoring

Agency GSA Monitored Frequency of Monitoring Period of Record of Monitoring Types of Wells Monitored Number of Wells (approximate) Known Completion

• f Wells Monitored

Number of Dual Completion Wells Auotomated Monitoring Alta Irrigation District EK, GK Monthly to bi- annually 1921 - 2011 Ag / Domestic 5 None None Unknown Bureau of Reclamation All Monthly to bi- annually 1924 - 2008 Unknown 118 15 Unknown Unknown Cal Water (City of Visalia) MK, GK monthly 1971 - 2018 Municipal 104 None Unknown Unknown City of Lindsay EK bi-annually 2016 - 2017 Municipal 3 None None Unknown City of Tulare MK Monthly to bi- annually 1992 - 2018 Municipal 30 11 None Unknown Deer Creek & Tule River Authority None? Bi-annually 2011 - 2018 Ag / Domestic 1 None None Unknown Department of Water Resources All Bi-annually 1930 - 2016 Various 182 7 Unknown Unknown Exeter Irrigation District EK, GK Bi-annually 1963 - 2016 Agricultural 40 None Unknown Unknown Ivanhoe Irrigation District EK Bi-annually 1961 - 2014 Agricultural 36 Few to none Unknown Unknown Kaweah Delta Water Conservation District GK, MK, (EK?) Monthly to bi- annually 1919 - 2018 Agricultural 425 30 4 Unknown Kings County Water District GK, MK Monthly to bi- annually 1963 - 2017 Agricultural 100 3 Unknown Unknown Kings River Conservation District GK Bi-annually 2011 - 2018 Agricultural 6 3 Unknown Unknown Lakeside Irrigation Water District GK, MK Bi-annually 2012 - 2017 Agricultural 33 2 Unknown Unknown Lewis Creek Water District EK Bi-annually 1971 - 2016 Agricultural 3 1 Unknown Unknown Lindmore Irrigation District EK Bi-annually 1945 - 2016 Agricultural 104 1 Unknown Unknown Lindsay-Strathmore Irrigation District EK Bi-annually 1955 - 2016 Agricultural 7 None Unknown Unknown Pixley Irrigation District EK Rarely 1940 - 1960 Agricultural 1 None Unknown Unknown Porterville Irrigation District EK Rarely 1960 - 1978 Agricultural 1 None Unknown Unknown Stone Corral Irrigation District EK Bi-annually 2006 - 2016 Agricultural 6 1 Unknown Unknown Tulare Irrigation District MK Bi-annually 1945 - 2018 Agricultural 128 5 4 Unknown Lower Tule River Irrigation District EK Bi-annually 1953 - 2010 Agricultural 10 1 Unknown Unknown Westlands Water District EK Bi-annually 1920 - 2018 Agricultural 1 None Unknown Unknown Total: 1,344 8

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Questions?