Implementing California’s Sustainable Groundwater Management Act (SGMA): Implementing California’s Sustainable Groundwater Management Act (SGMA)

Ostrom Workshop Colloquium Presentation | February 29th, 2016

This research effort is guided by the following overarching research question: What can be learned from existing groundwater management arrangements in Californ

This research effort is guided by the following overarching research question: What can be learned from existing groundwater management arrangements in California — adjudications, special act districts, and select AB 3030 planning processes and county ordi nances — to inform the creation of durable, sustainable groundwater management plans under California’s new Sustainable Groundwater Management Act? The current and planned research described in this presentation is being conducted with a team of researche rs at Stanford University’s Woods Institute on the Environment, Water in the West Program, and Gould Center on Dispute Resolution. Preliminary work is being supported by a grant from Stanford’s Environmental Ventures Program (Janet Martinez, PI).

Implementing SGMA: Results from a Stakeholder Survey

University of California, Davis (UC Davis) | August 26th, 2019

The Sustainable Groundwater Management Act (SGMA) of 2014 represents a historic transition to collective groundwater resource management and has the potential to signif

The Sustainable Groundwater Management Act (SGMA) of 2014 represents a historic transition to collective groundwater resource management and has the potential to significantly reduce groundwater overdraft in California. A total of 260 groundwater sustainability agencies (GSAs) recently formed to collectively manage groundwater resources in the 127 high and medium priority groundwater basins of the state. The simultaneous formation of hundreds of new governing agencies is an unprecedented institutional effort with very few examples to learn from. As GSAs move towards the design and deliberation of their groundwater sustainability plans (GSPs), assessments on the process up until now can directly inform development processes that are still taking place. This report summarizes the results from a state-wide survey that targeted SGMA participants.

Improving Groundwater Security in the United States

The White House | December 14th, 2024

The U.S. is facing a serious and unprecedented groundwater challenge. In many aquifers, groundwater withdrawal has outpaced natural recharge, which is exacerbated by the

The U.S. is facing a serious and unprecedented groundwater challenge. In many aquifers, groundwater withdrawal has outpaced natural recharge, which is exacerbated by the changing climate and precipitation variability. Much of the water in the major aquifers in the U.S. is fossil water, recharged over 10,000 years ago, and will not be replaced naturally on human timescales. In the western U.S., groundwater resources are being depleted at alarming rates, mostly from agricultural withdrawal. The depletion has caused land subsidence and earth fissures as well as permanent reduction of storage capacity. The depletion has national and global consequences as non-renewable groundwater in the west is embedded in agricultural products transported to the rest of the U. S. and in agricultural commodities exported globally. Many federal agencies have programs to measure the quality and quantity of groundwater, as well as conservation programs for sustainable use of groundwater. PCAST applauds and endorses their efforts as well as those by state governments, non-governmental organizations, professional organizations, local communities, private citizens, and others, to manage their groundwater resources. To ensure the sustainability of this indispensable resource and mitigate risks from its depletion, it is imperative that we enhance our understanding and management of groundwater resources.

Incomplete Determination for Groundwater Sustainability Plan submitted for Owens Valley Subbasin (Basin No. 6-012.01)

California Department of Water Resources (DWR) | April 14th, 2025

Incomplete Determination of the 2020 Eastern San Joaquin Subbasin Groundwater Sustainability Plan

California Department of Water Resources (DWR) | January 28th, 2022

The Department of Water Resources (Department) has evaluated the groundwater sustainability plan (GSP) submitted for the Eastern San Joaquin Subbasin (Subbasin) and has d

The Department of Water Resources (Department) has evaluated the groundwater sustainability plan (GSP) submitted for the Eastern San Joaquin Subbasin (Subbasin) and has determined that the GSP is incomplete. The Department based its determination on recommendations from the Staff Report, included as an enclosure to the attached Statement of Findings, which describes that the Eastern San Joaquin Subbasin GSP does not satisfy the objectives of the Sustainable Groundwater Management Act (SGMA) nor substantially comply with the GSP Regulations. The Staff Report also provides corrective actions which the Department recommends to address the identified deficiencies.

Incomplete Determination of the 2020 Groundwater Sustainability Plans Submitted for the San Joaquin Valley – Kern County Subbasin

California Department of Water Resources (DWR) | January 28th, 2022

Department management has reviewed the enclosed Staff Report, which recommends that the deficiencies identified should preclude approval of the Plan. Based on its review

Department management has reviewed the enclosed Staff Report, which recommends that the deficiencies identified should preclude approval of the Plan. Based on its review of the Staff Report, Department management is satisfied that staff have conducted a thorough evaluation and assessment of the Plan and concurs with, and hereby adopts, staff’s recommendation and all the corrective actions provided. The Department thus deems the Plan incomplete based on the Staff Report and the findings contained herein. A. The GSPs do not establish undesirable results that are consistent for the entire Subbasin. 1. While the Coordination Agreement presents Subbasin-wide undesirable results, the Subbasin’s fragmented approach towards establishing management criteria that define undesirable conditions in various parts of the Subbasin does not satisfy SGMA’s requirement to use same data and methodologies. B. The Subbasin’s chronic lowering of groundwater levels sustainable management criteria do not satisfy the requirements of SGMA and the GSP Regulations. 1. The GSPs relied on disparate methods to develop groundwater level minimum thresholds across the numerous GSPs and management areas. 2. The GSPs do not consistently and sufficiently document the effects of their selected minimum thresholds on beneficial uses and users in the Subbasin, nor explain how the minimum thresholds and measurable objectives that are set below historical lows will impact other applicable sustainability indicators, specifically water quality, land subsidence, and reduction of groundwater storage. C. The Subbasin’s land subsidence sustainable management criteria do not satisfy the requirements of SGMA and the GSP Regulations. 1. The Plan lacks a Subbasin-wide, coordinated approach to establishing land subsidence sustainable management criteria. 2. The GSPs and management areas that use their minimum thresholds for the chronic lowering of groundwater levels as proxy criteria for subsidence do not sufficiently demonstrate that groundwater levels (specifically groundwater levels below historical lows) are a reasonable proxy to avoid land subsidence that would substantially interfere with surface land uses.

Indian Wells Valley Groundwater Basin Groundwater Sustainability Plan

Indian Wells Valley Groundwater Authority (IWVGA) | January 14th, 2020

Currently, the groundwater resources in the Indian Wells Valley Groundwater Basin (IWVGB or Basin) are not being sustainably managed. Overdraft conditions have existed fo

Currently, the groundwater resources in the Indian Wells Valley Groundwater Basin (IWVGB or Basin) are not being sustainably managed. Overdraft conditions have existed for decades as a result of groundwater pumping that exceeds the natural Basin yield (Dutcher and Moyle, 1973). The results of overdraft have manifested themselves through various undesirable results, primarily the chronic lowering of groundwater levels, the degradation of water quality, and the reduction of groundwater in storage throughout the IWVGB. (See Section 3 for a discussion of overdraft conditions in the Basin.) In compliance with the Sustainable Groundwater Management Act (SGMA), as set forth in California Water Code (CWC) Section 10720.1, this Groundwater Sustainability Plan (GSP) discusses Basin management strategies that will culminate in the absence of undesirable and unsustainable groundwater conditions in the IWVGB. The GSP recommends management actions and projects, and provides measurable sustainability objectives and milestones that are intended to achieve Basin sustainability while considering the unique geologic and hydrogeologic conditions of the IWVGB. The recommendations of this GSP will provide for long-term sustainable groundwater management in the IWVGB within 20 years of GSP implementation. Due to size, this file has been divided. Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7

Indigenous communities, groundwater opportunities

American Association for the Advancement of Science (AAAS) | August 3rd, 2018

Instead of managing fresh water as one integrated resource, laws frequently treat groundwater separately from more visible, monitored, and managed surface waters. One und

Instead of managing fresh water as one integrated resource, laws frequently treat groundwater separately from more visible, monitored, and managed surface waters. One under-recognized consequence of such legal fragmentation has been uncertainty about whether water rights for indigenous communities, which have been addressed in many countries to varying degrees for surface waters, apply to groundwater. In late 2017, the U.S. Supreme Court left standing a lower court ruling endorsing priority groundwater rights for Native American tribes by denying an appeal in Agua Caliente Band v. Coachella Valley Water District. This ruling establishes a new standard throughout nine western states within the lower court's jurisdiction and establishes persuasive, although nonbinding, legal precedent for the rest of the United States. To evaluate the ruling's broader potential impacts, we present new data cataloging existing Native American water rights and mapping unresolved tribal groundwater claims across the western United States. No court considered such a regional or national quantitative catalog or map. Drawing lessons from past U.S. experience, we then discuss how tribal rights may offer new opportunities to achieve sustainable groundwater management for society at large, with implications beyond the United States. *The full text of this paper is behind a Science Magazine pay wall at a single-issue cost of $15. It should be available for free through research portals at universities, and may be accessible through public libraries with Science Magazine subscriptions. A free summary is contained by the August 3, 2018 Stanford News report "Stanford study reveals the changing scope of Native American groundwater rights – and opportunities for better freshwater management."    

Integrated Hydrologic Model of Pajaro Valley, Santa Cruz and Monterey Counties, California

U.S. Geological Survey (USGS) | September 5th, 2014

Increasing population, agricultural development (including shifts to more water-intensive crops), and climate variability are placing increasingly larger demands on avail

Increasing population, agricultural development (including shifts to more water-intensive crops), and climate variability are placing increasingly larger demands on available groundwater resources in the Pajaro Valley, one of the most productive agricultural regions in the world. This study provided a refined conceptual model, geohydrologic framework, and integrated hydrologic model of the Pajaro Valley. The goal of this study was to produce a model capable of being accurate at scales relevant to water management decisions that are being considered in the revision and updates to the Basin Management Plan (BMP). The Pajaro Valley Hydrologic Model (PVHM) was designed to reproduce the most important natural and human components of the hydrologic system and related climatic factors, permitting an accurate assessment of groundwater conditions and processes that can inform the new BMP and help to improve planning for long-term sustainability of water resources. Model development included a revision of the conceptual model of the flow system, reevaluation of the previous model transformed into MODFLOW, implementation of the new geohydrologic model and conceptual model, and calibration of the transient hydrologic model. The conceptual model identified inflows and outflows that include the movement and use of water from natural and human components. The groundwater flow system is characterized as a layered geologic sedimentary system through which downward flow is driven by the combined effects of the application of irrigation water at the land surface and the pumping of groundwater from deeper in the system. Overall, groundwater meets most of the agricultural demand in the initial part of the growing season, augmented by precipitation during wet winter and spring seasons. In addition, the amount of groundwater used for irrigation varies from year to year in response to climate variation and can increase dramatically in dry years. Data on agricultural pumpage is a major component of simulated outflow that was previously unavailable; therefore, a coupled farm-process model was used to estimate historical pumpage for Pajaro Valley by subregion (water-balance subregions) as well as the delivery of surface water to and from the Harkins Slough Aquifer-Storage-and-Recovery System (HS-ASR) and related Coastal Distribution System (CDS) since 2002. The new, integrated hydrologic model includes new water-balance subregions; delineation of natural, municipal, and agricultural land use; streamflow networks; regions of tile drains; and, the groundwater flow system. The redefinition of the geohydrologic framework and incorporation into the simulation revealed the importance of the confining units at the base of the alluvial deposits and between the upper and lower Aromas Sand for regional groundwater flow.

James Groundwater Sustainability Agency Groundwater Sustainability Plan

James Groundwater Sustainability Agency (JGSA) | December 12th, 2019