Aliso Water District Groundwater Sustainability Plan (Amended)

Aliso Water District Groundwater Sustainability Agency | July 7th, 2022

The January 2020 AWD GSA GSP, along with the other GSPs of the Delta-Mendota Subbasin, was deemed incomplete by DWR January 21, 2022 (Appendix H). The incomplete determin

The January 2020 AWD GSA GSP, along with the other GSPs of the Delta-Mendota Subbasin, was deemed incomplete by DWR January 21, 2022 (Appendix H). The incomplete determination provided 180 days to respond to the deficiencies identified by DWR. Subsequently, multiple consultations with DWR and meetings of the Delta-Mendota GSP groups were held to develop a coordinated response. This GSP, including the Common Chapter (Appendix B), addresses the concerns of DWR’s January 2022 Determination Letter. Due to size, this file has been divided. Part 1, Part 2, Part 3, Part 4, Part 5

Amended Groundwater Sustainability Plan, Tri-County Water Authority - Tule Subbasin

Tri-County Water Authority | July 27th, 2022

The Tule Subbasin submitted six GSPs, including one for the Tri-County Water Authority, in January 2020 to the Department of Water Resources (DWR). DWR was required to de

The Tule Subbasin submitted six GSPs, including one for the Tri-County Water Authority, in January 2020 to the Department of Water Resources (DWR). DWR was required to determine whether the GSPs conformed to the specific requirements of SGMA. DWR issued a single determination letter for the Tule Subbasin commenting on all six GSPs. In a letter dated January 28, 2022, DWR determined that that the GSP is incomplete. DWR stated that the GSP was considered incomplete as “it does not define undesirable results or set sustainable management criteria for groundwater levels, subsidence, and water quality in the manner consistent with SGMA and the GSP regulations.” Upon receiving the incomplete determination, the Subbasin had 180 days to address the identified deficiencies and submit revised GSPs by July 27, 2022. The TCWA is submitting this 2022 Amended GSP to address the three deficiencies outlined in the determination letter. Due to size, this file has been divided. Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7, Part 8, Part 9

Amended Olcese Groundwater Sustainability Plan (GSP) for Certain Lands Overlying the Kern County Subbasin

Olcese Groundwater Sustainability Agency | July 27th, 2022

This GSP has been prepared by the Olcese GSA, which is the GSA for the portion of the Kern County Subbasin of the San Joaquin Valley Groundwater Basin (Department of Wate

This GSP has been prepared by the Olcese GSA, which is the GSA for the portion of the Kern County Subbasin of the San Joaquin Valley Groundwater Basin (Department of Water Resources [DWR] Basin No. 5-022.14, referred to herein as the “Kern Subbasin” or “Basin”) that underlies the Olcese Water District (“OWD” or “District”). The area that is covered by this GSP is referred to herein as the “Olcese Groundwater Sustainability Agency Area” or “Olcese GSA Area” and is located in the eastern portion of the Kern Subbasin. The Kern Subbasin is one of 21 basins and subbasins identified by the DWR as being critically overdrafted, a designation that triggers an accelerated timetable for GSP development by 2020 and achievement of sustainability by 2040. As of June 2022, a total of 14 GSAs, including the Olcese GSA, have been formed within the Kern Subbasin and a total of six GSPs have been prepared by these various GSAs. This Olcese GSP has been developed in coordination with the other GSPs for the Kern Subbasin to meet SGMA regulatory requirements1 while reflecting the unique hydrogeologic conditions within the Olcese GSA Area and preserving local control over water resources. Pursuant to the SGMA GSP submittal deadline, the Olcese GSP was originally submitted to DWR in January 2020; this amended Olcese GSP is in response to DWR’s 28 January 2022 letter entitled Incomplete Determination of the 2020 Groundwater Sustainability Plans Submitted for the San Joaquin Valley – Kern County Subbasin. Together, the Kern Subbasin GSPs provide a path to maintain the long-term sustainability of locally managed groundwater resources now and into the future. Due to size, this file has been divided. Part 1, Part 2

An Evaluation of California’s Adjudicated Groundwater Basins

University of California, Santa Cruz (UC Santa Cruz) | October 1st, 2016

Groundwater is a critical resource in California, providing on average 30 percent of the state’s total water supply and significantly more during dry years. Many commu

Groundwater is a critical resource in California, providing on average 30 percent of the state’s total water supply and significantly more during dry years. Many communities rely exclusively on groundwater, and it is an essential back-up source of water during droughts when pumping increases significantly to compensate for reduced surface supplies. Local groundwater management agencies, special act districts, and court adjudications are the primary institutional arrangements to manage groundwater in California. Increasing groundwater declines in many areas of the state and concomitant negative impacts prompted the passage of the 2014 Sustainable Groundwater Management Act (SGMA). The SGMA established new requirements for 127 high- and medium-priority groundwater basins that are either in overdraft or vulnerable to overdraft to develop sustainable management programs with increased state oversight. The SGMA defines sustainable groundwater management as: “The management and use of groundwater in a manner that can be maintained during the planning and implementation horizon without causing undesirable results.” Undesirable results include: chronic lowering of groundwater levels; significant and unreasonable reduction of groundwater storage; significant and unreasonable seawater intrusion, degraded water quality, and land subsidence; depletions of interconnected surface water that have significant and unreasonable adverse impacts on beneficial uses of the surface water. The SGMA exempts 388 basins categorized as low- and very-low priority, as well as all the adjudicated groundwater basins and 3 basins with pending groundwater adjudications. The SGMA was followed by the passage of Assembly Bill 1390 (AB 1390) and Senate Bill 226 (SB 226) in 2015 that provide some procedures for groundwater adjudications. In the adjudication of a groundwater basin, the court generally defines and determines water rights for all users and provides court-supervised basin management by a Watermaster, who is usually appointed by the court to ensure that the basin is managed in accordance with the court’s decree. Prior to adjudication, key stakeholders and users of the groundwater in a basin often negotiate a stipulation and physical solution to manage the basin, and the court can then accept it in whole or in part, or reject it and craft a different solution to manage the basin. There is limited analysis of the history and current condition of California’s adjudicated basins and the potential for future improvements to the adjudication process. This report for the State Water Resources Control Board (SWRCB) evaluates all of California’s adjudicated basins with respect to sustainable groundwater management as defined in SGMA including: accomplishments, challenges, how management can be improved, and whether there are common elements that result in the sustainable management of an adjudicated groundwater basin.

Anderson Subbasin Groundwater Sustainability Plan

Enterprise Anderson Groundwater Sustainability Agency | January 20th, 2022

This GSP covers all of the 98,700 acres of the Anderson Subbasin. The GSP describes the current groundwater conditions and hydrogeologic conceptual model, establishes a

This GSP covers all of the 98,700 acres of the Anderson Subbasin. The GSP describes the current groundwater conditions and hydrogeologic conceptual model, establishes a water budget, outlines local sustainable management criteria (SMC or SMCs), and describes projects and management actions for maintaining sustainability through the GSP planning and implementation period. Due to size, this file has been divided into 9 parts. Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7, Part 8, Part 9

Annual Investigation and Report of Groundwater Conditions within United Water Conservation District

United Water Conservation District (UWCD) | March 8th, 2016

Approaches for groundwater management in times of depletion and regulatory change

University of California, Davis (UC Davis) | June 1st, 2018

New legislation and related regulations in California mandate groundwater management to avoid undesirable results from excessive groundwater pumping and other hum

New legislation and related regulations in California mandate groundwater management to avoid undesirable results from excessive groundwater pumping and other human activities. Required aspects of management planning that will occur in well over 100 alluvial groundwater sub-basins across the state include scientific foundation and public transparency. While the details of individual groundwater management approaches will be particular to conditions in each management area, there will be common elements based on similar aspects of many groundwater systems in the state. The process of beginning to implement groundwater management for a large part of the state poses challenges. Use of scientific knowledge and methods of analysis developed in academia and industry will be helpful to the overall effort. This dissertation considers aspects of groundwater management that are expected to be common among many planning efforts. Inactive water supply wells acting as conduits for contaminant migration is considered through field examples and use of recently available databases regarding existing well constructions and water quality. Nonpoint source pollution effects on groundwater quality from conduit wells are investigated and selective regulatory action is explored as an option for addressing an issue that is too large for complete solution with available resources. Options for managed aquifer recharge are explored for a combined urban-agricultural area through use of a recently released land use database. A hydro-economic analysis is performed using linear programming to evaluate the efficacy of an on-farm recharge approach. Future work may include development of additional insights within the context of the study areas presented as well as extensions that consider new geographic areas and additional related considerations.

Approved Determination of the Revised Groundwater Sustainability Plan Submitted for the San Joaquin Valley – Merced Subbasin

California Department of Water Resources (DWR) | August 4th, 2023

Assessment of Interconnected Subbasins

Butte County | June 30th, 2017

The Sustainable Groundwater Management Act (SGMA) requires groundwater sustainability agencies (GSAs) to develop groundwater sustainability plans (GSPs) that achieve sust

The Sustainable Groundwater Management Act (SGMA) requires groundwater sustainability agencies (GSAs) to develop groundwater sustainability plans (GSPs) that achieve sustainable groundwater management within 20 years of adoption. All critically overdrafted basins must adopt GSPs by January 31, 2020; all other medium and high priority basins must complete GSPs by January 31, 2022. Since many subbasins are hydrologically connected to adjoining subbasins, sustainable groundwater management will require accounting for groundwater interactions with adjoining subbasins. Often, adjoining subbasins will use different analytical methods or apply different levels of technical rigor. Many GSAs are concerned that different methodologies for developing interbasin flows can lead to different results that will call into question the ability to achieve sustainability and would potentially create issues with SGMA compliance. This effort evaluated opportunities and barriers for agencies to account for interconnected basin dynamics through the collaboration of technical experts focused on a portion of the northern Sacramento Valley Integrated Regional Water Management (NSVIRWM) Plan area. As interbasin flows (i.e., groundwater flow between interconnected basins) cannot be directly measured, the project reviewed available tools to investigate how they may or may not be suitable for use in estimating interbasin flows within the region. This process highlighted areas for local agencies to consider in addressing interbasin issues, developed a framework for analysis in other areas of the state, and identified areas where the state and federal government can assist local agencies implementing SGMA. This report is developed to provide summary level information appropriate for decision makers, with more detailed technical information and examples provided in the appendices or by reference. Interbasin flow is groundwater entering or exiting a defined subbasin through its boundaries in the subsurface and may vary significantly in space and time based on the dynamics of inflow and outflow from the basins. Interbasin flows are driven by differences in groundwater levels (i.e. head gradients) across the basin boundary. Groundwater levels are, in turn, impacted by processes on the land surface. Land use and crop acreages drive water demand in a subbasin and indirectly drive groundwater pumping, which has a direct effect on groundwater levels (i.e., groundwater heads). The direction and magnitude of interbasin flow depends on the groundwater head gradient across the basin boundary and the conductivity of the aquifer materials. It is widely recognized that the groundwater subbasins in the Sacramento Valley, and throughout the Central Valley, are interconnected to varying degrees. The Sacramento Valley Groundwater Basin includes many subbasins, extends over a wide geographic area, and includes numerous established and eligible GSAs. With interconnected subbasins, management decisions and actions in one subbasin may influence one or more adjoining subbasins. Such influence may positively or negatively impact sustainability. Thus, interbasin flows become critical to both GSAs’ development of GSPs and to DWR reviewing GSPs.

Assessment of Interconnected Subbasins: Regional Collaboration and Model Selection Process

Groundwater Resources Association of California (GRA) | October 3rd, 2017

In basins with complex spatial and temporal variations in water budget components, integrated groundwater-surface water modeling is the best approach to quantify and eval

In basins with complex spatial and temporal variations in water budget components, integrated groundwater-surface water modeling is the best approach to quantify and evaluate interbasin groundwater flows.