DWR Takes Next Steps Towards Groundwater Sustainability


A location used to measures the water depth at specific agricultural wells in Colusa County

A location used to measures the water depth at specific agricultural wells in Colusa County on March 17, 2016.

California has reached a major milestone in its implementation of the landmark Sustainable Groundwater Management Act (SGMA). The California Department of Water Resources (DWR) has completed the official assessments for the first-ever groundwater sustainability plans developed by local agencies and submitted in 2020 to set and achieve sustainability goals over a 20-year period. This milestone is the result of a lot of hard work by local agencies, backed by state investments to support local SGMA decision-making and implementation efforts.


The department has completed assessments for 20 groundwater basins, containing a total of 42 plans, including critically overdrafted basins that provide water supply for millions of Californians, agriculture and the environment.


“Bringing our groundwater basins into sustainability will provide the state with long-term drought resiliency, but it is not going to be easy,” said DWR Director Karla Nemeth. “These initial plans are the first step in a 20-year effort to solve decades-long challenges. With the added complexities of climate change upon us, now is the time for locals and the State to come together and lead with courage to tackle these challenges head-on.” 


Groundwater accounts for 40 percent of the state's total annual water supply in normal years and almost 60 percent in drought years. For decades, however, more water has been pumped out of groundwater basins than has been replenished, which has led to declining groundwater levels in nearly 100 basins across the state.


The enactment of SGMA set forth a statewide regulatory framework for improving the management of critical groundwater resources. Importantly, SGMA recognizes that each basin is unique and provides tools and authorities for local groundwater sustainability agencies (GSAs) to manage their basins in cooperation with their community members. Despite the 20-year timeline to reach sustainability, SGMA requires near-term actions by GSAs, including conducting ongoing monitoring, collecting data, updating plans, and carrying out projects and actions to assure sustainable groundwater conditions for future generations.

To date, DWR has issued official assessments for 20 groundwater basins, representing 42 plans, as some basins contain multiple plans. A summary of the status of basins with plans submitted in 2020 is provided below and more detailed information can be found on the SGMA Portal:


Basins with approved plans:

  1. Santa Cruz Mid-County Basin 3-001
  2. 180/400 Foot Aquifer Subbasin 3-004.01
  3. North Yuba Subbasin 5-021.60
  4. South Yuba Subbasin 5-021.61
  5. Oxnard Subbasin 4-004.02
  6. Pleasant Valley Basin 4-006
  7. Las Posas Valley Basin 4-008
  8. Indian Wells Valley Basin 6-054

Basins with incomplete plans:

  1. Eastern San Joaquin Subbasin 5-022.01
  2. Merced Subbasin 5-022.04
  3. Chowchilla Subbasin 5-022.05
  4. Delta-Mendota Subbasin 5-022.07
  5. Kings Subbasin 5-022.08
  6. Westside Subbasin 5-022.09
  7. Kaweah Subbasin 5-022.11
  8. Tulare Lake Subbasin 5-022.12
  9. Tule Subbasin 5-022.13
  10. Kern County Subbasin 5-022.14
  11. Paso Robles Subbasin 3-004.06
  12. Cuyama Valley Basin 3-013


The basins that have received approved plans are expected to continue moving forward with their local planning and implementation efforts. DWR expects to see specific sections of these plans updated during the first five-year plan update due in 2025.


The basins that have received incomplete determinations have 180 days from the release date of the assessments to correct the deficiencies in their plans, including key issues related to impacts on drinking water, land subsidence and interconnected surface water and groundwater. During this 180-day period, DWR staff is offering meetings with the agencies in these basins to provide clarification on the deficiencies identified in the written assessment. Additionally, DWR provides ongoing facilitation support services to help GSAs and local water management groups foster discussions among diverse water management interests and jurisdictions. Failure to resolve the deficiencies within 180 days will initiate consultation with the State Water Resources Control Board for possible State intervention. The Water Board’s role in implementation of SGMA is to step in temporarily to manage groundwater resources in groundwater basins where local agencies are not on track to sustainable management within the required 20-year timeline. In keeping with the principle of effective local control that underpins the Act, the Board’s involvement would continue only until local agencies are on track to sustainably manage groundwater resources themselves. The Board would provide direction to agencies on deficiencies in their basin plans that must be addressed to end state management.


This SGMA milestone represents the first phase in a process of ongoing work, including the submittal of another round of GSPs that were due by January 31, 2022. DWR received all of the plans that were required to be submitted in 2022 - 63 basins containing 65 plans - and will begin reviewing these plans, as well as continue to review annual reports and assess updated plans every five years to determine if the GSAs are on track to meet their basin’s sustainability goals.

A significant amount of work has gone into the development of the plans submitted by local agencies in 2020 and the evaluation of the plans by DWR. The department is communicating these decisions with the local managers in these basins and recognizing the local leadership and investment to manage groundwater more sustainably. The State will continue to provide available resources (facilitation, data and tools, and grant funding) to support ongoing local efforts to improve plans and work towards sustainability. 


From the onset of SGMA, the state has made tremendous investments to ensure local agencies have the tools they need to be successful, including providing grants to local agencies for planning and project implementation, facilitation support, and technical support services.

DWR’s Sustainable Groundwater Management (SGM) Grant Program provides essential funding to assist local GSAs to develop and implement sustainable groundwater planning and projects. Approximately $150 million in planning grants has been awarded to date through three rounds of solicitations. The Implementation Grant Program was designed to fund projects and programs that will assist local agencies as they implement groundwater sustainability plans. DWR awarded $26 million in Proposition 68 funding during the spring 2021 as part of its first round of the Implementation Grant Program. The 2021-22 state budget included $300 million over the next several years for grants to support local planning and implementation of groundwater sustainability plans across groundwater basins. This funding will help local agencies address known data gaps, plan and implement projects, and address deficiencies in sustainability plans.

In addition to funding, DWR has provided educational toolkits for the public, guidance documents and outreach and engagement toolkits for GSAs, and facilitation and written translation services to support GSA engagement with local interested parties including non-English speaking communities. On an ongoing basis, DWR shares groundwater educational videos in various languages, press releases, webinars, and educational materials about SGMA, GSP development and GSP evaluations.

DWR has a long history of collecting groundwater data and making it publicly available. Since the onset of SGMA, and ongoing drought conditions in California, DWR’s data collection and technical assistance efforts have ramped up quickly. DWR staff has installed 15 stream gauges and 33 new monitoring wells in basins throughout the state to help GSAs fill data gaps in their plans. In response to drought conditions in 2021, DWR enhanced the MyDryWaterSupply (now MyDryWell) webpage where local governments, GSAs and individuals can report dry wells. In November 2021, DWR released California’s Groundwater (B-118) Update 2020 and its complementary CalGW Live website and dashboard tools – a powerful new interactive, easy-to-use tool that allows people to customize dashboards conveying the latest information about wells, groundwater levels, and subsidence. The C2VSimFG model, Groundwater Conditions Update Report and Maps have been updated, and the Statewide Subsidence dataset has been updated through the 2021 water year with quarterly data releases beginning in 2022. In 2021, DWR launched the first statewide Airborne Electromagnetic (AEM) surveys, initiating this three-year program and providing extensive outreach to the public and tribes. The 2021-2022 state budget includes $18 million for enhanced groundwater monitoring, a groundwater accounting tool and data standards, and enhanced surveys to better manage drinking water, groundwater recharge, and groundwater-dependent ecosystems.

California’s historic ongoing drought conditions illustrate the importance of managing for sustainable groundwater conditions. By tracking groundwater conditions and performance under SGMA, and other DWR programs, state and local agencies can better manage water resources during average and wet years to ensure groundwater will be available as a drought buffer during dry years when there is less precipitation and snowpack.For more information about the plan assessment process, visit DWR’s Groundwater Sustainability Plan webpage and GSP Evaluation Fact Sheet.