Office of the Delta Watermaster
The Office of the Delta Watermaster – Background
The Office of the Delta Watermaster was created as part of the Delta Reform Act of 2009. The Watermaster is an independent officer of the State, appointed to a four-year term by the State Water Resources Control Board, reporting jointly to the Water Board and to the Delta Stewardship Council.
Important Reminder!
- Due April 1, 2022 – Water use reports for the nine-month period between January 1 and September 30, 2021 were due by April 1, 2022. Click here for “What’s New for 2022” for more information.
- Meeting Announcement - Water Use in the Legal Delta Under Drought Conditions (7/14/2022)
- Term 91 Is Now In Effect; Diversion under Term 91 Licenses are Curtailed until Further Notice (6/3/2022)
- The New Yorker highlights “The Biggest Potential Water Disaster in the United States." (5/11/2022)
- The Public Policy Institute of California published its Policy Brief: “Tracking Where Water Goes in a Changing Sacramento-San Joaquin Delta.” (5/2022)
- Order Denying Reconsideration of the Adoption of the August 2021 Emergency Curtailment and Reporting Regulation for the Sacramento-San Joaquin Delta Watershed (5/9/2022).
- Revised Consensus Strategy for Avoiding Duplicative Reporting of Water Diversion and Use in the Legal Delta (2/22/2022)
- Delta Conservancy unveils 2022 Pilot Program grants to gather data on water conservation and quality protection actions in the Delta (1/19/2022)
- Delta Alternative Compliance Plan (water use measurement) has been posted for public review and comment (12/21/2021)
- What's New for 2022 - New Legislation Consolidates All Water Use Reporting Periods and Due Dates (11/24/2021)
- Delta Drought and Curtailment Webpage
- State Water Board alerts water users to prepare for persistent dry conditions (03/22/2021)
- Continued dry conditions prompt early warning about potential water shortages
Water users urged to reduce and conserve (03/22/2021) - Delta water community seeks voluntary consensus on strategy to avoid duplicative water use reporting (2/01/2021)
- Development team announces progress on OpenET to measure crop water use. Press release and supporting materials here. (9/15/2020)
- Final Decision in Modesto Irrigation District v. Heather Robinson Tanaka clarifies bases of riparian claims in the Delta (8/31/2020)
- Governor's Resilience Portfolio finalized (7/28/2020)
- On Feb. 4, 2020, the CA Natural Resources Agency and the CalEPA unveiled a substantial revised Framework of Voluntary Agreements to update and implement the Bay-Delta Water Quality Control plan. The presentation slides supported their presentation. The slides are available on the Office of the Delta Watermaster’s webpage via this link (1/4/2020)
- The Department of Water Resources has completed the scoping process for the environmental review of its proposed single tunnel Delta Conveyance project (7/2020)
- Statement Analysis Master (Excel Spreadsheet) Summarizing Staff's Review of Responses to 2015-0002 Informational Order (9/1/2020)
- Role of the Delta Watermaster
- Biography - Michael George, Delta Watermaster
- Lindsay Kammeier and Beti Girma, Water Resource Control Engineers, were accepted into the 2020 Water Leaders program sponsored by the Water Education Foundation (1/15/2020)
- State Water Resources Control Board
- Email List Subscription
- Delta Stewardship Council
- Delta Conservancy
- North Delta Water Agency
- Central Delta Water Agency (Under Construction)
- South Delta Water Agency
Water Rights Reporting
- Frequently Asked Questions
- Water Rights Ownership and Contact Information Updates
- Annual Water Diversion and Use Reporting Help
- Annual Water Use Reporting Requirements for Water Right Holders (Water Right Type, Water Use Report Deadlines, How to Report Water Use, Measurement Information)
- Measurement Information
- eWRIMS – Electronic Water Rights Information Management System (Fact Sheet, Database to View Water Rights, Web Mapping Application, Report Management System and Help Center)
- Click Here to File Your Water Use Report (eWRIMS – Report Management System)
Delta Measurement Experimentation Consortium
- Delta Alternative Compliance Plan Description (12/21/2021)
- Delta Measurement Experimentation Consortium - History and Purpose
Overlap Memo
- Memo Regarding Claimed Overlap Between Riparian and Pre-1914 Water Rights in the Delta and Frequently Asked Questions (06/06/2018)
2015 Informational Order
- Cover Memo: Summary of Preliminary Review of Responses to Informational Order WR 2015-0002-DWR
- Informational Order 2015-0002-DWR
- Frequently Asked Questions on the Pre-1914 and Riparian 2015 Informational Order Response Review Summary (2/20/2018)
Access the 2015 Informational Order FTP Document Repository
General Water Rights Resources
- Delta Science Program
- Bay Delta Program
- Statement of Diversion and Use Program
- Yolo Bypass Memorandum of Understanding
- Challenges Facing the Sacramento - San Joaquin Delta
- Delta Atlas
- San Francisco Estuary Institute - A Delta Renewed November 2016 (11/29/2016)
Programs
Studies
Publications and Articles
Legal
- Video: The Delta Watermaster’s periodic report to the State Water Board (February 1, 2022) is available here – Starts at 1:14:30 (2/1/2022)
- Video: CA Water Blog – Unraveling the Knot – Water Movement in the Sacramento-San Joaquin Delta, Episode #1(Reprise), #2 (Tidal Forces), #3 (Managing Flows) (2/20/2020)
- Video: The Delta Watermaster’s Periodic report to the State Water Board (October 5) - Starts at 6:26:16 (10/5/2021)
- Video: The Delta Watermaster’s regular quarterly report to the Delta Stewardship Council (September 23, 2021) – Starts at 1:14:44 (9/23/2021)
- Presentation to CA Water Commission regarding cross-Delta conveyance (Courtesy of Maven) (05/05/2021)
- Video: The Delta Watermaster’s Periodic report to the State Water Board (May 4) is available here (5/4/2021) - Starts at 2:46:07
- Video: Ted Sommer presents Hydrology 101 (4/27/2021)
- Video: The Delta Watermaster’s regular quarterly report to the Delta Stewardship Council (February 25, 2021) is available here – Starts at 40:56 (2/25/2021)
- Video: The Delta Watermaster’s Semi-annual report to the State Water Board (December 15) is available here (12/15/2020) - Starts at 2:47:06
- Video: The Delta Watermaster’s regular quarterly report to the Delta Stewardship Council (October 22, 2020) is available here (10/22/2020) - Starts at 1:18:37 (11/17/2020)
- Video: The Delta Watermaster was the featured presenter at the recent Water Policy Forum sponsored by the Municipal Water District of Orange County. The Forum video is here. (9/23/2020)
- Video: Delta Watermaster Semi-Annual Report to the State Water Board (07/21/2020) - Starts at 2:17:15
- Video: Quarterly Report on current Delta Science Issues – SWRCB Meeting (10/16/2018) - Starts at 2:24:15
- Video: Quarterly Report on current Delta Science Issues – SWRCB Meeting (07/10/2018) - Starts at 2:37:35
- Video: Crop Study Presentation - SWRCB Meeting (05/01/2018) - Starts at 2:19:18
- Video: Quarterly Report on current Delta Science Issues – SWRCB Meeting (03/20/2018) - Starts at 37:00
- Video: 2015 Informational Order WR-2015-002: Release of Staff Findings – Erik Ekdahl and Michael George (2/20/2018)
- Video: Delta Stewardship Council Explains How it Works to Protect Delta Farmland (12/27/16)
- Measurement Fair Presentation (8/22/2016)
- Delta Issues Presentation to the California Water Association (05/19/2016)
- Diversion Reduction Program Presentation to the State Water Resources Control Board (05/03/2016)
- Presentation to the Suisun Marsh Landowners Workshop (04/20/2016)
- Quarterly Watermaster update to Delta Stewardship Council (03/24/2016)
- Delta Protection Commission (03/17/2016)
- Presentation to Nixon Peabody (09/24/2015)
- Supplemental Statements of Water Diversion and Use May 2013
- Statements of Water Diversion & Use Water Diversion Measurement Public Workshop (07/21/2011)
- A Comparative Study for Estimating Crop Evapotranspiration in the Delta (05/01/2018)
- 2015 Voluntary Diversion Reduction program among in-Delta Riparian Water Right Claimants (03/11/2016)
- Local Water Governance in the Delta (09/25/2014)
- California’s Area of Origin Laws (10/08/2013)
- Gates and Barriers in the Delta (04/23/13)
- Term 91: Stored Water Bypass Requirements (12/04/2012)
- Improving Water Right Enforcement Authority (09/19/2012)
- Water Right Compliance and Enforcement in the Delta (02/07/2012)
- Statements of Water Diversions and Use: Providing a Better Picture of Water Use in the Delta (11/01/2011)
- The State Water Resources Control Board’s Role in Implementing the Delta Plan Report (03/15/2011)
- The Reasonable Use Doctrine and Water Use Efficiency Report (01/19/2011)
- Bay-Delta Water Quality Control Plan
- Summary of Proposed Updates to the Bay-Delta Water Quality Control Plan (9/15/2016)
- The Delta Plan (Delta Stewardship Council) (4/26/2018)
- EcoRestore
- Plan Bay Area
- San Francisco Bay Basin Plan
- Bay Area Integrated Regional Water Management Plan
- California Water Action Plan
- Frequently Asked Questions on the Pre-1914 and Riparian 2015 Informational Order Response Review Summary (2/20/2018)
- State Water Board Revokes Water Right License for Failure to Report Annual Diversions (8/7/2019)
- SWRCB Releases Proposed Flow and Salinity Objectives (9/15/2016)
- To save SF Bay and its dying Delta, state aims to re-plumb California
- Watermaster:Understanding the Sacramento-San Joaquin Delta Crisis
- Regulators Prepare Water Diverters for Stepped-up Reporting Rules
- Two Hearts Beating Not Quite As One
- California’s Agtech-Focused Plan for Tackling Its Ongoing Water Problem
Responsibilities
The Watermaster is responsible for overseeing the day-to-day administration of water rights, and, when necessary, for taking enforcement action, related to water diversions within the Delta. The Watermaster also confers with and assists both the Water Board and the Stewardship Council as they carry out their respective legislative mandates to achieve the dual objectives of enhancing the Delta ecosystem and improving water supply reliability within the constraints of the water rights system and of the Delta as an evolving place.
The Delta – The Hub of California’s Water Management System
The Delta is an inland estuary located at the confluence of the Sacramento and San Joaquin Rivers just before their outlet to San Francisco Bay and the Pacific Ocean. The Delta is comprised of a network of islands, channels and wetlands which make up the largest estuary on the Western Coast of the United States. The Delta is the hub of California’s water management system as well as an important ecological system supporting a variety of species, several of which are protected under endangered species acts. The Delta ecosystem and the water management facilities located there are under pressure from a variety of natural and man-made stressors including:
- water diversions from its natural tributaries;
- withdrawal of a portion of its water to meet the needs of users throughout the State;
- invasive species which compete with or prey upon its endangered natives;
- the constant risk of salinity intrusion from the Ocean and of salinity concentration by farming;
- degradation in its water quality from historic causes such as hydraulic mining and current causes such as farm and urban runoff;
- channelization of its waterways and the fragility of some of its levees;
- oxidation and erosion of friable peat soils which have left some islands subsided below the surrounding water table;
- complex (and sometimes conflicting) regulatory constraints; and
- a clash of public and private interests that has generated decades of litigation and conflict.
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Photo credit: Department of Water Resources
Contacts
For Questions or Comments
Contact the Office of the Delta Watermaster:
U.S. Mail:
Office of the Delta Watermaster
State Water Resources Control Board
P.O. Box 100
Sacramento, CA 95812-0100
Email: deltawatermaster@waterboards.ca.gov
Kristi Matal
Communication and Outreach Specialist
Email: Kristi.Matal@waterboards.ca.gov
Phone: 916-319-8264