The Chowchilla Subbasin exists within the larger San Joaquin Valley Groundwater basin, as described in the California Department of Water Resources Bulletin 118. The County of Madera is the exclusive GSA for the portion of the Chowchilla Subbasin in the unincorporated area of the County, and not otherwise covered by another public agency. Other GSAs in the Chowchilla Basin include Chowchilla Water District, Triangle T Water District and Merced County. If you’re not sure what GSA you are in for the Madera Subbasin, use this interactive map.

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2025 Revised Chowchilla GSP

Chowchilla Subbasin GSP 2025 Public Review Flyer
Chowchilla GSP  – Clean
Chowchilla GSP  – Redline

• Appendix 1A-1F
• Appendix 2A-2C, Appendix 2D-2E, Appendix 2F-2G
• Appendix 3A-3C, Appendix 3D, Appendix 3D-Redline, Appendix 3E, Appendix 3F – Part A, Appendix 3F – Part B, Appendix 3G-3J, Appendix 3H-Redline, Appendix 3K-3O, Appendix 3K-Redline, Appendix 3L-Redline, Appendix 3M-Redline, Appendix 3N-Redline, Appendix 3O-Redline
• Appendix 4A-4D
• Appendix 6A-6C;  Appendix 6D – Part A, Appendix 6D – Part B, Appendix 6D – Part C

2024 Revised Chowchilla GSP Public Review Draft 

Chowchilla GSP Public Review Draft -Clean
Chowchilla GSP Public Review Draft – Tracked Changes
Chowchilla GSP Chapter 2 Figures
Chowchilla GSP Chapter 3 Figures
Appendix 1.A-1.F
Appendix 2.A-2.G
Appendix 3.A-3.C
Appendix 3.D Redline
Appendix 3.E
Appendix 3.F – Part A
Appendix 3.F – Part B
Appendix 3.G
Appendix 3I-3J
Appendix 3K Redline
APPENDIX 3L Redline
APPENDIX 3M Redline
APPENDIX 3N Redline
APPENDIX 3O Redline
Appendix-4.A-4.D-1
Appendix 6

• Chowchilla Subbasin GSP Public Review Flyer

 2023 May Revised Chowchilla GSP

Chowchilla Revised GSP – Clean
Chowchilla Revised GSP – Tracked Changes
Chowchilla GSP Chapter 2 Figures
Chowchilla GSP Chapter 3 Figures
Appendix 1.A-1.F
Appendix 2.A – 2.C.e
Appendix 2.D-2.E
Appendix 2.F
Appendix 2.G
Appendix 3.A – 3.D
Appendix 3.E
Appendix 3.F Part A
Appendix 3.F Part B
Appendix 3.G – 3.H
Appendix 3.I – 3.J
Appendix 4.A-4.D
Appendix 6.A – 6.C
Appendix 6.D
Appendix 6.D – A
Appendix 6.D – B
Appendix 6.D – C
Appendix 6.D – D
Appendix 6.D – E
Chowchilla Subbasin Revised GSP Matrix

2022 July Revised Chowchilla GSP 

Chowchilla GSP Revised July 2022 Cover Letter
Chowchilla GSP Revised July 2022 Matrix Deficiencies and Revisions
Chowchilla_GSP_Edits_2022_Tracked_Changes
Figure 2 Chow GSP Update
Figure 2 Chow GSP Update
Figure 2 Chow GSP Update
Figure 3 Chow GSP Update
Figure 4 Chow GSP Update
Resolution 2022-104
Appendix 1 A to F Chow GSP Update
Appendix 2 Plan Area & Basin Setting
Appendix 3 Sustainable Management Criteria
Appendix 3 Sustainable Management Criteria
Appendix 4 Chow GSP Update
Appendix 5 & 6 Plan Implementation and References & Technical Studies
Appendix A Chow GSP Update
Appendix B Chow GSP Update
Appendix C Chow GSP Update
Appendix D Chow GSP Update
Appendix E Chow GSP Update
Technical Memorandum Chowchilla Domestic Well Inventory

2020 January Chowchilla GSP 

Final GSP and Appendices:
Chowchilla GSP
List of Comments
Chapter 2 Figures
Chapter 3 Figures
Appendix 1
Appendix 2 A-B
Appendix 2 C a-d
Appendix 2 C.e
Appendix 2 D-E
Appendix 2 F.a-e
Appendix 3 A-D
Appendix 4
Appendix 5
Appendix 6 A-C
Appendix 6 D Groundwater Model Documentation
Appendix 6 D Groundwater Model Report Figures

Chowchilla GSP Annual Reports

Chowchilla GSP Annual Report Water Year 2024
Chowchilla GSP Annual Report Water Year 2023
Chowchilla GSP Annual Report Water Year 2022
Chowchilla GSP Annual Report Water Year 2021
Chowchilla GSP Annual Report 2021; Appendices
Chowchilla First Annual Report April 2020; Appendices

Chowchilla Subbasin Meetings 

2025

March 26, 2025 – GSP Advisory Committee Meeting Water Year 2024 Annual Report
January 24, 2025 – Chowchilla Subbasin 2025 Revised GSP Public Workshop, Recording link for Chowchilla Subbasin – Revised GSP Public Workshop Webinar

2024

August 16, 2024- Chowchilla Subbasin Revised GSP Public Workshop

2023

March 15, 2023 – Chowchilla Subbasin GSP Advisory Committee Agenda; 9/28/22 Minutes

2022

January 14, 2022 – Chowchilla Subbasin GSP Advisory Committee GSP Revisions Presentation; Agenda; 3/17/2021 Minutes
March 23, 2022 – Chowchilla Subbasin GSP Advisory Committee
Chowchilla Subbasin 2022 GSP Annual Report Presentation Chowchilla Subbasin GSP Revisions Presentation
June 23, 2022 – Chowchilla Subbasin GSP Advisory Committee Domestic Well Mitigation Program MOU Presentation
July 6, 2022 – Chowchilla Subbasin GSP Advisory Committee GSP revisions Presentation
September 13, 2022 – Chowchilla Subbasin Allocation BOS Chowchilla Subbasin Allocation Presentation
December 20, 2022 – Public Meeting Domestic Well Mitigation in Chowchilla Subbasin

2021 

March 17, 2021 Chowchilla Subbasin GSP Advisory Committee Agenda; GSP Annual Report Presentation

2019

February 7, 2019 – Madera & Chowchilla Subbasin Technical Workshop Agenda; Flyer in English; Flyer in Spanish; Minutes
March 27, 2019 – Chowchilla GSP Advisory Committee GSP Preparation Presentation
May 29, 2019 – Chowchilla GSP Advisory Committee GSP Preparation Presentation
July 31, 2019 – Chowchilla GSP Advisory Committee GSP Preparation Presentation
October 23, 2019 – Chowchilla GSP Advisory Committee Chowchilla Subbasin GSP Highlights Presentation
November 20, 2019 – Chowchilla GSP Advisory Committee Public Comment Review Presentation