GROUNDWATER
SUSTAINABILITY PLAN
ADOPTION
Council Water Committee
October 10, 2024
Agenda Item No. 24-1040
What is SGMA?
• The Sustainable Groundwater Management Act,
or SGMA, is statewide legislation (2014) that
establishes a path for the sustainable
management of groundwater for the first time in
California’s history
What Does SGMA Require?
• Groundwater Sustainability Agencies (GSAs) must be
formed. GSAs must prepare and submit the initial
Groundwater Sustainability Plans (GSPs) by:
• January 2020, for critically overdrafted basins
• Updates every 5 years
• GSPs must include measurable objectives and
milestones to achieve sustainability within 20 years of GSP adoption
• GSAs must assess progress every 5 years after initial GSP submittal through Periodic Evaluations (PEs)
• GSP development must be open and transparent
Basin Setting
• The Eastern San Joaquin
Groundwater Subbasin
(Subbasin) is one of 21 basins
identified by the California
Department of Water
Resources (DWR) as being in a
state of critical overdraft
• SGMA requires preparation of
a Groundwater Sustainability
Plan (GSP) to address
measures necessary to attain
sustainable conditions in the
Subbasin
Eastern San Joaquin Groundwater Authority
One GSP for 16
Separate Groundwater
Sustainability Agencies
Within the GWA
Updated every 5 years
GSP Timeline
✓ January 2020 GWA submits GSP to DWR
✓ January 2022 DWR completed review & identifies GSP deficiencies ✓ July 2022 GWA submits 2022 revised GSP
✓ July 2023 GWA receives DWR approval with 8 corrective actions October 2024 Presentation to WAG & CWC
November 2024 Notice in Stockton Record (14 day minimum public review) December 2024 City Council to hold public notice hearing to consider GSP adoption
January 2025 GSP submitted to DWR
The GSP – What’s In It?
7 1. Agency Information, Plan Area,
& Communication
1. Basin Setting
• Hydrogeologic Conceptual Model
• Current & Historical Conditions
• Water Budget
2. Sustainable Management Criteria
3. Monitoring Networks
4. Data Management System
5. Projects & Management Actions
6. Plan Implementation
7. References
Sustainability Indicators
•Chronic Lowering of Groundwater Levels
•Reduction in Groundwater Storage
•Seawater Intrusion
•Degraded Water Quality
•Land Subsidence
•Depletion of Interconnected Surface
Water
DWR’s Recommended Corrective Actions
(RCAs)
9 5) Add additional justification
for 2,000 mg/L chloride
isocontour line
6) Revise ISW SMC and
monitoring network
7) Improve Rep MN for GWQ
8) Develop chloride isocontour
line in western portion of
Subbasin
1) Justify GWL MT and
undesirable results
2) Revise subsidence SMC using
direct subsidence monitoring
data
3) Update water budgets using
recalibrated model
4) Revise estimate for reduction
of groundwater storage volume
and UR definition
Periodic Evaluation
1 0
• SGMA requires that GSAs evaluate the GSP every
5 years and whenever the Plan is amended to:
• Provide status of groundwater conditions
• Discuss progress towards meeting interim milestones & measurable objectives
• Describe advancement of projects and management
actions and unforeseen challenges
• ESJ Subbasin’s first Periodic Evaluation is due
January 29, 2025 along with the 2024 Amended
GSP
• Together, these documents address the 8 Recommended
Corrective Actions
Completing the 5-Year Update
1 1
Address 8 recommended
corrective actions
Prepare 2024 GSP
Amendment Prepare Subbasin’s first
Periodic Evaluation
Hold public open house
& public review period
GSA adoption of GSP
Amendment & approval of
Periodic Evaluation
Submit all documentation by
January 29, 2025 deadline
Near-Term SGMA Efforts
1 2
1. Conduct spring & fall monitoring
• GWL
• GWQ
• Subsidence
2. Complete Annual Reports
• Initiate DMS structure updates for 2025 Annual Report • Model data updates
3. Begin development of Demand Management Program
4. Execute relevant elements of Communication &
Engagement Plan
City of Stockton Sustainability Efforts
• Regular water quality monitoring and
groundwater elevation measurements
• Support of GSP preparation and active GWA
participation
• Reduced groundwater pumping
• Projects
•Delta Groundwater Recharge Basin
•Groundwater recharge of up to 20,000 AFY
•Advanced Meter Infrastructure
•Water conservation of 2,000 AFY
GSP Published on Eastern San
Joaquin Groundwater Authority
Website: esjgroundwater.org
Recommendation
Recommend the City Council adopt the
GSP and authorize the GWA to submit
the GSP to the DWR.