Basin Boundary Modifications
The Sustainable Groundwater Management Act (SGMA) established a process for to ask DWR to revise the boundaries of existing groundwater basins or subbasins, including establishing new subbasins. We developed the after extensive outreach to SGMA advisory groups, partners, local agencies, and members of the public. The Basin Boundary Emergency Regulations were adopted on October 21, 2015 and the provisions of the emergency regulation went into effect on November 16, 2015.
After the Basin Boundary Emergency Regulations were adopted DWR provided an online to inform local agencies and the public about the existing Bulletin 118 groundwater basins and other relevant geologic and geographic data. DWR’s enabled local agencies to submit their requests for Basin Boundary Modifications online and the public to view those requests and public comments.
The Final 2018 Basin Boundary Modifications were developed after a technical review of the basin boundary modification requests and public comments. DWR held a public meeting and a public presentation to the California Water Commission to present the Draft Basin Boundary Modifications and technical review process. The Final Basin Boundary Modifications were released February 11, 2019.
Access the Results
(includes letters and request summaries)
Assessment Tool (BBAT)
(Online Web Map)
- Final 2018 Basin Boundary Modifications released February 11, 2019
- The next Basin Boundary Modifications period is not scheduled and is not anticipated prior to 2022
Frequently Asked Questions
The Final 2016 Basin Boundary Modifications were developed through DWR's technical review of basin boundary modification requests and public comment made during the submission period, January 1, 2016 through March 31, 2016. DWR then held a series of public meetings to present the Draft Approved Basin Boundary Modifications, provide an overview of the BBMRS and technical review process, answer clarifying questions and receive further public comments on the Draft Approved Basin Boundary Modification submissions. After a technical review of the requests and public comments, DWR developed the list of 2016 Final Basin Boundary Modifications and adopted them into the 2016 Bulletin 118 Interim Update.
There were many complex issues and challenges associated with the Bulletin 118 – Update 2003 basin boundaries. We met and continue to do so with various organizations, agencies, and individual experts to receive input on these basin boundary issues that create potential difficulties with SGMA implementation. We have and will continue to consider these basin boundary issues and challenges throughout the rule‐making process.
Between April 28th and May 1st of 2015, DWR completed three public listening sessions and one webinar related to the Basin Boundary Regulations. The given during the listening sessions and a recording of the are available for viewing in these internet links.
Based on the feedback collected during the scoping period, which included substantial communication and outreach with numerous local agencies and advisory groups to better understand local perspectives related to boundaries, DWR released a in April 2015.
Local agencies and interested parties had the opportunity to provide input during the preparation of the draft basin boundary regulations and before the regulations were adopted. We held three required public meetings in late August. The draft basin boundary emergency regulations are posted below.
- Draft Basin Boundary Emergency Regulations (July 17 Draft)
- Draft Basin Boundary Emergency Regulations Technical Factsheet (July 17 Draft)
- Public Meetings and Comment Process Factsheet
- California Water Commission (July 15) Basin Boundary Presentation
- Draft Fiscal Cost Analysis for Proposed Modifications to Basin Boundaries Basin Boundary Public Meetings - August 31
- Presentation on Draft Basin Boundary Emergency Regulations
- Recording of Webcast
The proposed emergency regulations have been refined based on public and Commission comments.
- Proposed Basin Boundary Emergency Regulations (October 8 – Clean version)
- Proposed Basin Boundary Emergency Regulations (October 8 – Strikeout version)
- Basin Boundary Emergency Regulations Factsheet (October 8)
Basin Boundary Modification Request System
The Basin Boundary Modification Request System (BBMRS) allows users to view basin boundary modification requests made by local agencies.
Basin Boundary Assessment Tool
The Groundwater Basin Boundary Assessment Tool (BBAT) is a web-based application to inform local agencies and the public about the existing Bulletin 118 groundwater basins and other relevant geologic and geographic data.
- Initial Notification Guidance Document
- Modification Request Guidance Document
- Public Input Guidance Document
- Printable Template for Boundary Modification Request Submissions
- Considerations When Submitting Spatial Data
- Groundwater Basin Boundary Webinar Recording 12-17-15
- Presentation from Groundwater Basin Boundary Webinar 12-17-15