Basin prioritization classifies the California’s 517 basins and subbasins into priorities based on components identified in the California Water Code. The priority of basins and subbasins determines whether CASGEM and SGMA provisions apply in any given basin. The priority process consists of applying datasets and information in a consistent, statewide manner in accordance to the provisions in California Water Code Section 10933(b).
In 2014, DWR prioritized groundwater basins through its California Statewide Groundwater Elevation Monitoring (CASGEM) Program, which was established in response to the legislation enacted in California's 2009 Comprehensive Water package. The 2014 CASGEM Basin Prioritization classified basins as high, medium, low, or very low based on the consideration of factors described in the legislation.
Following the adoption of Sustainable Groundwater Management Act (SGMA) and the Basin Boundary regulations, DWR received 54 requests for basin boundary modifications. In the fall of 2016, DWR completed and released the final groundwater basin boundaries, which incorporated numerous statewide jurisdictional and scientific modifications. DWR published Bulletin 118 – Interim Update 2016, which included the boundary modifications, on December 22, 2016.
The SGMA requires that DWR reassess the prioritization anytime DWR updates Bulletin 118 basin boundaries. The 2018 SGMA Basin Prioritization process and draft results are provided below.
2018 SGMA Basin Prioritization
Following the release of the 2016 Basin Boundary Modifications, DWR began the 2018 SGMA prioritization of California’s 517 groundwater basins (Water Code 12924(b)) defined in Bulletin 118. Prioritization has changed for some basins due to the consideration of impacts from local habitat and local streamflows, the change in area of basin as a result of boundary modifications, and incorporation of newly available data sources. DWR will conduct public meetings to present the draft results and solicit public comments.
How to Access the Results
The 2018 SGMA Basin Prioritization process and draft results can be accessed below:
|Basin Prioritization Dashboard
(online web map)
| 2018 SGMA Basin Prioritization
Process and Draft Results document
|Spreadsheets and data
at CNRA Open Data
Timeline and Next Steps
The following table is the anticipated schedule for finalizing the 2018 SGMA Basin Prioritization.
|Prioritization based on 2016 Basin Boundary Modifications|
|Public Comment Period Opens||May 18, 2018|
|Webinar||May 30, 2018|
|Public Meetings||June 25-28, 2018|
|Public Comment Period Closes||August 20, 2018|
|Finalize Prioritization (based on 2016 Basin Boundary Modifications)||mid-November|
|Prioritization based on 2018 Basin Boundary Modifications|
|Release of Draft Prioritization for Modified Basins||late February|
|Public Comment Period||February - March|
|Release of Final Prioritization (based on 2018 Basin Boundary Modifications)||May 2019|
*Last modified on 7/24/2018. All dates are subject to change.
Public Meetings and Comments
Public meetings will be held to go over the process and solicit public comments on the draft results.
The public comment period opened on May 18, 2018 and closed after 90 days on August 20, 2018. Statewide data consistent with the 2018 SGMA Basin Prioritization Process and Results document may be provided in support of comments.
Frequently Asked Questions on Basin Prioritization
Answers to frequently asked questions provided below or in the Frequently Asked Questions on Basin Prioritization document.
Prioritization is the classification of groundwater basins based on a variety of factors identified in statute, such as population and the number of water wells in a basin (see Water Code § 10933). DWR was first directed to prioritize basins as part of the Groundwater Monitoring legislation adopted in 2009, with the purpose being to establish the order in which DWR would evaluate basins to determine whether monitoring provided sufficient information to demonstrate seasonal and long‐term trends in groundwater elevations, as required by that law. DWR created the California Statewide Groundwater Elevation Monitoring (CASGEM) Program in response to the Groundwater Monitoring legislation, and released the CASGEM prioritization of basins in 2014. The Sustainable Groundwater Management Act (SGMA), which became effective in 2015, required DWR to prioritize basins for purposes of SGMA shortly after the law took effect (see Water Code § 10722.4). DWR adopted the 2014 CASGEM Basin Prioritization as the initial SGMA Basin Prioritization in 2015.
SGMA requires DWR to reassess groundwater basin prioritization any time it updates Bulletin 118 boundaries. Publication of Bulletin 118 Interim Update 2016 triggered the need to reassess the 2015 SGMA Basin Prioritization. DWR’s reassessment indicated a need to prioritize basins whose SGMA compliance status was uncertain as a result of the basin boundary modifications, as well the need for reprioritization based on the presence of new and enhanced information, and the consideration of factors specifically relevant to SGMA.
DWR prioritizes groundwater basins based on factors such as population, irrigated acreage, and the number of wells (see Water Code §10933). Most factors are neutral as to groundwater management, focusing simply on the importance of groundwater in a basin. As a result, a sustainable managed basin may be designated as high-priority based on which factors are present. Changes in status from the 2014 CASGEM prioritization generally reflects changed conditions or new information about existing conditions. Changes in status are not meant as a comment on changes to groundwater management in that basin.
Although SGMA applies to all basins in California, only high- and medium-priority basins are required to adopt a GSP or submit an alternative. Low- and very low-priority basins may adopt these plans, but are not required to. A low- or very low-priority basin reclassified as high- or medium-priority will be required to adopt a GSP or submit an alternative. A high- or medium-priority basin reclassified as low- or very low-priority will no longer be required to adopt a GSP or submit an alternative. SGMA does not treat low-priority basins differently than very low-priority basins. SGMA does not treat high-priority basins differently than medium-priority basins. For this reason, a change from medium- to high-priority does not affect requirements under SGMA.
DWR used the same process for the 2018 SGMA Basin Prioritization as was used for the 2014 CASGEM Basin Prioritization. A description of the prioritization process can be found in the following documents:
Water Code §10720.8 identifies adjudicated areas in SGMA, which have an existing defined entity administering the adjudication. Under SGMA, adjudicated portions of basins are exempt from developing a groundwater sustainability plan (GSP) and forming a groundwater sustainability agency (GSA). However, the entities administering the adjudications are subject to submitting annual reports to DWR by April 1 each year. SGMA requires that annual reports include the following information for the portion of the basin subject to adjudication:
a) Groundwater elevation data unless submitted pursuant to Water Code §10932.
b) Annual aggregated data identifying groundwater extraction for the preceding water year.
c) Surface water supply used for or available for use for groundwater recharge or in-lieu use.
d) Total water use.
e) Change in groundwater storage.
f) The annual report submitted to the court.
DWR will accept public comments for approximately 90 days following the release of draft results. DWR will conduct public meetings in June 2018 on the 2018 SGMA Basin Prioritization process after the draft release. The final 2018 SGMA Basin Prioritization will consider input received during the public comment period.
For more information regarding how to comment, visit the website at the following link:
DWR expects to release the final 2018 SGMA Basin Prioritization results in November 2018. In parallel with the analysis and release of the draft 2018 SGMA Basin Prioritization results, DWR initiated the submission period for the 2018 Basin Boundary Modification process. The deadline for submitting Basin Boundary Modification requests is September 28, 2018. DWR will consider modification requests and will develop draft recommendations in winter 2018-2019. In coordination with this effort, DWR will finalize the 2018 SGMA Basin Prioritization results in February 2019 for those basins not affected by the 2018 Basin Boundary Modification process. The priority of basins with proposed boundary modifications will be finalized in May 2019, after the 2018 Basin Boundary Modification process is complete and after any new boundaries are defined.
The current timeline for 2018 SGMA Basin Prioritization and 2018 Basin Boundary Modification projects can be found on the Basin Prioritization web page.
Basins previously ranked as low- or very low priority that are prioritized as high- or medium-priority are subject to SGMA and have additional time to form Groundwater Sustainability Agencies (GSAs) and develop and implement GSPs or to submit an alternative (see Water Code § 10722.4(d)). If a basin is reprioritized from low or very low to high- or medium-priority, the following deadlines apply:
- Two years from Final Basin Prioritization to form a GSA
- Two years from Final Basin Prioritization to submit an alternative
- Five years from Final Basin Prioritization to develop a GSP
Basins previously prioritized as high- or medium-priority that are now low- or very low-priority are not subject to the requirements in SGMA to form a GSA and prepare a GSP or an alternative to avoid potential State Water Resources Control Board intervention. However, these basins are still encouraged to form GSAs and develop GSPs, update existing groundwater management plans, and coordinate with others to develop a new groundwater management plan in accordance with Water Code Section 10750 et seq.
DWR provides a variety of services and support to GSAs including Facilitation Support, Technical Support Services, Communication and Engagement, and Financial Assistance.
Basin Points of Contact
DWR has designated Basin Points of Contacts (POCs) to assist local agencies as GSPs are developed and implemented. Once the 2018 SGMA Basin Prioritization is finalized, POCs will be identified for those new high- and medium-priority basins. For more information, please contact your DWR regional office representatives identified below:
- Northern Region: Bill Ehorn, Bill.Ehorn@water.ca.gov, (530) 528-7403
- North Central Region: Bill Brewster, Bill.Brewster@water.ca.gov, (916) 376-9657
- South Central Region: Dane Mathis, Dane.Mathis@water.ca.gov, (559) 230-3354
- Southern Region: Tim Ross, Timothy.Ross@water.ca.gov, (818) 549-2345
DWR has developed a suite of data, tools, guidance documents, and references to assist in the development and implementation of GSPs. Throughout the SGMA implementation horizon, DWR will continue to develop relevant and useful tools with open access to necessary data and scientific information, in addition to providing access to Basin Points of Contacts. Resources available now include:
- Monitoring Well Installation
- Groundwater Level Monitoring Training
- Borehole Video Logging
- Other Field Activities
- Identification and engagement of interested parties
- Meeting facilitation
- Interest-based negotiation/consensus building
- Public outreach facilitation
- DWR Region Office Contacts
- Communication and Engagement Digital Toolkit
- Integrated Regional Water Management
- Water Quality or Drinking Water
- Water Supply or Management
- Water Use Efficiency
DWR offers a variety of services and assistance to support GSA development of GSPs. DWR is funding Technical Support Services and Facilitation Support Services to aid GSAs that includes meeting facilitation, field activities, modeling and mapping.
In addition to the technical and facilitation support, DWR offers several Integrated Regional Water Management (IRWM) Grant programs. IRWM Grant programs fund planning, implementation, and disadvantaged community involvement. At this time, there are no additional Proposition 1 funds remaining for the Sustainable Groundwater Planning Grant program; however, DWR may administer another round of solicitation should any new funds become available. There are additional grant programs with open solicitations available which may be applicable.
Yes, GSAs or local agencies who received grants from the Sustainable Groundwater Planning Grant Program have the option to use the funding to proceed with development and adoption of a GSP and the project scope defined in the grant agreement or to return the funding to DWR.
In January 2014, we conducted five public comments. Final 2014 Basin Prioritization results are compiled into a . You can also visit our , a web-based application that includes a layer depicting Basin Prioritization information.to introduce draft 2014 Basin Prioritization results and solicit
The Water Code requires a statewide prioritization, to the extent that data are available, of California's groundwater basins using the following eight components (Water Code §10933):
- Rate of population growth
- Number of public supply wells
- Total number of wells
- Total irrigated acreage
- Degree to which persons overlying the basin rely on groundwater as their primary source of water
- Documented impacts on the groundwater within the basin, including overdraft, subsidence, saline intrusion, and other water quality degradation
- Any other information determined to be relevant by the department, including adverse impacts on local habitat and local streamflows
A priority designation of high, medium, low, or very low is assigned to each groundwater basin. For details on how changes in priority affect local agency compliance with SGMA, refer to establishment of Groundwater Sustainability Agencies (GSAs).