DATE: December 10, 2019
TO: Board of Supervisors
SUBMITTED BY: Steven E. White, Director
Department of Public Works and Planning
SUBJECT: Groundwater Sustainability Plan for San Joaquin River Exchange Contractors Groundwater Sustainability Agency in the Delta-Mendota Subbasin
RECOMMENDED ACTION(S):
TITLE
Adopt Resolution adopting the San Joaquin River Exchange Contractors Groundwater Sustainability Plan for portions of the Delta-Mendota Groundwater Subbasin including a portion of Fresno County Management Area B.
REPORT
Approval of the recommended action will adopt the portion of the Groundwater Sustainability Plan (GSP) for the San Joaquin River Exchange Contractors GSP Group in the Delta-Mendota Subbasin (Exchange Contractors GSP). The GSP covers a portion of Fresno County Management Area B (Management Area B) of the Delta-Mendota Subbasin (Subbasin), as required by the Department of Water Resources (DWR) to maintain and manage local groundwater resources. Information specific to the covered portion of Management Area B is in sections 1.3.11 and 16.0 of the Exchange Contractors GSP, and includes background information; historic, current, and projected water budgets; sustainable management criteria; projects and management actions that the County is anticipated to undertake; and additional information about implementation of the Exchange Contractors GSP. This item pertains to locations in District 1.
ALTERNATIVE ACTION(S):
Your Board may determine not to approve the recommended action; however, it would likely result in delay of submitting the required GSP by the January 31, 2020 deadline, as the County would be obligated to prepare a GSP for the portion of County lands that have been included in the Exchange Contractors GSP. If the GSP is not submitted by the deadline, intervention from the State Water Resources Control Board (State) could occur, which would result in the State managing local groundwater resources in the Subbasin.
FISCAL IMPACT:
Approval of the recommended action may result in an increase in Net County Cost. The Board approved the First Amendment to Memorandum of Understanding (MOU) No. 16-112-1 between the County and San Joaquin River Exchange Contractors Water Authority (SJRECWA) on December 12, 2017. The MOU provides that each party shall bear all costs with respect to its activities. To date, activities have been limited to Department of Public Works and Planning staff participation at various implementation meetings resulting in a cost approximately $5,000. The costs associated with the portion of Management Area B has received a portion of the Sustainable Groundwater Planning Grant (SGWP), grant funds awarded by DWR, within the Subbasin, which was approximately $172. This percentage, which is approximately half a percent, was based on acreage of land being covered by the Exchange Contractors GSP. Department staff costs are and will be absorbed within the Department’s Water & Natural Resources Org 4360 FY 2019-20 Adopted Budget. If there are significant implementation costs beyond the Department’s allocated resources, staff will return to your Board for direction and to request additional resource allocation.
DISCUSSION:
The Sustainable Groundwater Management Act (SGMA), signed into law September 16, 2014, and codified at Water Code sections 10720 to 10737.8, established a new structure for managing California’s groundwater resources at a local level by local agencies. SGMA allows the formation of locally controlled Groundwater Sustainability Agencies (GSAs) in the State’s higher priority groundwater basins. Each GSA is then required to develop and implement a GSP by January 31, 2020. Sustainability is defined as the management and use of groundwater in a manner that can be maintained during the planning and implementation horizon without causing undesirable results. Failure to implement a GSP and meet its’ sustainability goal could result in the State asserting its power to manage local groundwater resources.
Within the Subbasin 23 GSAs have been formed by various public agencies. Among these, the County serves as the exclusive GSA for Management Areas A and B, approximately 24,000-acre portion of the subbasin located roughly between the San Joaquin River east of the City of Mendota and the unincorporated community of Tranquility. Six GSPs for various areas within the Subbasin have been developed by multiple GSAs working together in a coordinated manner with the goal of achieving sustainability for the entire subbasin. When more than one GSP is developed to cover a groundwater subbasin, the responsible GSAs must coordinate management of the subbasin through an agreement that covers the entire subbasin, per Water Code, section 10727, subdivision (b)(3). The Board approved Coordination Agreement No. 18-502 for the Subbasin on August 21, 2018.
On March 15, 2016, the County and the SJRECWA entered into MOU No. 116-112 to implement SGMA for a portion of the Subbasin for the purpose of coordinating operations to achieve sustainable groundwater management and avoid conflict between SJRECWA’s implementation of SGMA and the County’s land use planning authorities.
On September 28, 2017, the Governor signed Senate Bill (SB) 372 (Chapter 357 Statutes of 2017) into law, creating the San Joaquin River Exchange Contractors GSA (Exchange Contractors GSA). Pursuant to SB 732, the Exchange Contractors GSA is the successor in interest to SJRECWA for all purposes related to SGMA, including the rights and responsibilities of the MOU, and is the exclusive GSA empowered to implement and enforce SGMA within the Exchange Contractors GSA boundary.
Within the exterior boundary of the Exchange Contractors GSA, exist a number of noncontiguous lands (County islands) that are part of Management Area B. To avoid duplication of efforts resulting from the proximity of the County islands to the Exchange Contractors GSA boundary, the County and the Exchange Contractors agreed to have these areas included in the Exchange Contractors GSP. Two amendments to the MOU, approved by the Board on December 12, 2017 and August 21, 2018, authorized the County islands to be included in the Exchange Contractors GSA GSP, and provided that the County will enforce the Exchange Contractors GSP within the County islands.
Department Staff have coordinated and will continue coordination of the implementation efforts with the Exchange Contractors GSP with a shared goal of sustainably managing groundwater resources.
Information specific to the portion of Management Area B that is covered by the Exchange Contractors GSP can be found in section 1.3.11, on page 14, and section 16.0, beginning on page 186 of the GSP, on file with the Clerk. Pertinent information is summarized as follows:
BACKGROUND INFORMATION
The portion of Management Area B that is included in the Exchange Contractors GSP is approximately 1,800 acres of land, as shown in Exhibit A. Of that, approximately 550 acres are actively farmed, and the remaining acres are not actively farmed and do not pump groundwater. This area of land has historically relied on groundwater extraction to meet demand. However, groundwater overdraft in this area has primarily been offset by recharge from within the SJRECWA service area and seepage from the San Joaquin River.
WATER BUDGETS
Groundwater pumping during the historic water budget period of 2003-2012 for the covered portion of Management Area B ranged from 100-acre to 1,200-acre feet per year, with an average annual extraction of 500-acre feet per year. For the Exchange Contractors GSP’s current year (2013) water budget, groundwater pumping was estimated to be 700-acre feet. Going forward it is anticipated that the demand for groundwater pumping is anticipated to remain about the same and that any increase in demand would be directedly tied to potential climate change.
SUSTAINABLE MANAGEMENT CRITERIA
The Exchange Contractors GSP establishes sustainable management criteria for each of the undesirable results required by SGMA including chronic lowering of groundwater levels, reduction in groundwater storage, land subsidence, surface water depletions, and water quality. Criteria for seawater intrusion was not included as this area is not subject to this issue.
The lands covered by the Exchange Contractors GSP, including the portion of Management Area B, have been sustainably managing groundwater levels for decades as evidenced in the SJREC’s annual groundwater studies dating back to the 1990’s. The measurable objectives for the chronic lowering of groundwater levels and reduction in storage is set to avoid shallow groundwater while maintaining levels above identified minimum threshold elevations for each management area to preserve groundwater storage.
Land subsidence, the gradual settling or sudden sinking of the Earth’s surface due to movement of earth materials, originating outside the boundary of the Exchange Contractors GSA is a significant concern. Impacts to infrastructure including reduced carrying capacity in canals and loss of gradient in gravity flow systems are realized when subsidence occurs. Wells within the portion of Management Area B covered by the Exchange Contractors GSP are constructed such that their pumping is not anticipated to cause subsidence. The County will work with the Exchange Contractors GSA to ensure future well permits are evaluated to avoid impacts.
The minimum threshold for depletions of interconnected surface water shall be the rate or volume of surface water depletions caused by groundwater use that has adverse impacts on beneficial uses of the surface water and that may lead to undesirable effects. The County will work with the Exchange Contractors GSA to establish construction criteria for new wells adjacent to the San Joaquin River to ensure that significant and unreasonable depletions of interconnected surface water are avoided as well as the potential to have direct depletion of surface water.
Salinity, the amount of dissolved salts in water, is the major groundwater quality concern throughout the Exchange Contractors GSP. Intercepting moderate to high salinity groundwater that is moving to the northeast in the area above the Corcoran Clay, which is a silty clay distributed throughout the western San Joaquin Valley, has been proven a feasible method of mitigation. The measurable object for degraded water quality is to continue to maintain soil health from the poor-quality groundwater migrating into the area from upslope lands.
PROJECTS AND MANAGEMENT ACTIONS
Although no projects or management actions are proposed at this time for the portion of Management Area B, the County is committed to offsetting groundwater if extractions in the future exceed our sustainable yield. The County is pursuing the option of purchasing groundwater credits or participating in recharge projects as a means to offset groundwater extractions when necessary. Also, the Exchange Contractors GSP states that it is anticipated that the County may impose groundwater extraction fees to recover its expenses. The Department will return to your Board at a later date for further direction on future funding of the Exchange Contractors GSP.
PLAN IMPLEMENTATION
Groundwater has been sustainably managed in this area for decades and will continue to be sustainably managed by the Exchange Contractors GSA. If issues are identified in the annual evaluations of Exchange Contractors GSP implementation efforts within the portion of Management Area B, the Exchange Contractors GSA will work with the County to address the concerns.
The County will continue to work with the Exchange Contractors GSA to meet SGMA requirements and maximize the benefits of local groundwater resources. The adoption of the Exchange Contractors GSP including portions of Management Area B by your Board is necessary to ensure that the Subbasin is entirely covered by adopted GSPs to meet the deadline requirements of SGMA.
Upon approval of all of the GSPs prepared within the Subbasin, including the Exchange Contractors GSP, the GSPs will be submitted to DWR for review and evaluation under Water Code, section 10733.4. Once DWR has performed a completeness review of the GSPs, they will then post the GSPs on its website for a 60-day public comment period. Once posted, DWR will have two years to issue an assessment of the GSPs. The assessment by DWR may include an approval or may include recommended corrective actions to address any deficiencies identified in the GSPs.
Under Water Code section 10728.6, the California Environmental Quality Act does not apply to the preparation and adoption of a GSP.
REFERENCE MATERIAL:
BAI #45 & #48 August 21, 2018
BAI #43 December 12, 2017
BAI #43 March 15, 2016
ATTACHMENTS INCLUDED AND/OR ON FILE:
Exhibit A
On file with Clerk - Resolution
On file with Clerk - SJRECWA GSA’s GSP (Advance Agenda Material)
CAO ANALYST:
Sonia M. De La Rosa