State Water Board Releases Final Draft Bay-Delta Plan Update, Updated Sacramento/Delta Flow Requirements

  • by California State Water Resources Control Board
  • Jul 6, 2018
  • Water News

Following nine years of research and extensive public outreach, the State Water Resources Control Board today released a final draft plan to increase water flows through the Lower San Joaquin River and its tributaries—the Stanislaus, Tuolumne and Merced rivers—to prevent an ecological crisis, including the total collapse of fisheries.

“The San Francisco Bay-Delta is an ecosystem in crisis. The board’s challenge is to balance multiple valuable uses of water—for fish and wildlife, agriculture, urban, recreation, and other uses,” said State Water Board Chair Felicia Marcus. “Californians want a healthy environment, healthy agriculture, and healthy communities, not one at the expense of the others. That requires the water wars to yield to collective efforts to help fish and wildlife through voluntary action, which the proposed plan seeks to reward.”

Release of the third and final draft of the Bay-Delta Water Quality Control Plan update for the Lower San Joaquin River and Southern Delta, and an accompanying Substitute Environmental Document, follows a nine-year process during which the board studied and analyzed options, conducted extensive public outreach, including public hearings in the area, and reviewed more than 1,400 comment letters. The board will begin consideration of the final draft plan in August.

The State Water Board also announced further progress on its effort to update flow requirements for the Sacramento River, its tributaries, and the Delta and its tributaries, including the Calaveras, Cosumnes and Mokelumne rivers. This update is at an earlier stage procedurally than the Lower San Joaquin River/Southern Delta plan update; a draft proposed plan and staff report analyzing alternatives will be released later this year for public review and comment.

The two Bay-Delta Plan updates are aimed at addressing an ecological crisis in the Delta and preventing further collapse of Bay-Delta fisheries. A dramatic decline in the populations of native fish species that migrate through and inhabit the Delta has brought some species to the brink of extinction. Approximately 70,000 fall-run Chinook salmon adults returned to the San Joaquin Basin in 1984. The number of returning adults dropped to approximately 40,000 in 2010 and again to 8,000 returning adults in 2014.

While multiple factors are to blame for the decline, the magnitude of diversions out of the Sacramento, San Joaquin, and other rivers feeding into the Bay-Delta is a major factor in the ecosystem decline.

The draft final Lower San Joaquin River/Southern Delta update includes improved instream flows February through June, which are the critical months for protecting migrating fish on the Stanislaus, Tuolumne and Merced rivers. These flows are measured as a percentage of “unimpaired flow,” the amount of water that would come down the river if there were no dams or other diversions.

A 40 percent of unimpaired flow requirement, within a range of 30 to 50 percent, is proposed as an appropriate balance for this plan update because it can improve conditions for fish and wildlife considerably without more challenging impacts on other water users. Currently, flows remaining in the rivers can run as low as 10 to 20 percent of unimpaired flow at critical times of the year and range from 21 to 40 percent on average for the three tributaries.

The unimpaired flow requirement is not intended to be a rigid and fixed percent of flow. The proposal provides for and encourages collaboration to use the flows as a block of water or “water budget” that can be allocated to “shape” or shift flows in time to better achieve ecological functions such as increased habitat, more optimal temperatures, or migration cues.

The draft plan recognizes that other “non-flow” factors, such as habitat loss, predation and pollution, affect survival rates of fish and other species. The plan would allow reduced river flows if stakeholders step up to pursue non-flow measures to improve conditions for fish and wildlife. Negotiations for voluntary agreements are taking place between stakeholders and the California Natural Resources Agency and its departments.

The draft final update also includes a revision of the salinity standard for the southern Delta. Maintaining an adequate amount of fresh water in the southern Delta is critical to protecting agriculture in the region. The year-round salinity standard in the draft final update increases slightly from the current seasonal standards, based on salinity tolerance studies of sensitive crops.

After consideration of public input, the draft text of the Proposed Final Amendments was modified. Those revisions can be found in Appendix K of the Draft Final Substitute Environmental Document. The State Water Board is accepting written comments on those changes until 12 p.m. (noon) on Friday, July 27, 2018. The hearing notice, additional background and instructions for submitting comments on the revisions can be found here.

A summary of the modifications and discussion of the changes can also be found in Volume 3, Master Response 2.1, Amendments to the Water Quality  Control Plan here. Board consideration of the Bay-Delta Water Quality Control Plan Update for the Lower San Joaquin River and Southern Delta will begin in August.



Suggested Resources

15 RESOURCES prev next
ACWA 2018 Fall Conference Presentations

Presentations from ACWA’s 2018 Fall Conference & Exhibition held Nov. 27-30 in San Diego are available below. Please note that […]

2018 Summary of Legislation

ACWA’s 2018 Summary of Legislation provides concise information on legislation enacted in the second year of the 2017-’18 legislative session that […]

California H2O: Flowing for the Future

ACWA and J Comm, Inc. have collaborated to create a 10-part video series to educate Californians about critical water issues. […]

ACWA’S 2018 Fall Legal Briefing and CLE Workshop Materials

The following presentations and materials for ACWA’s 2018 Legal Briefing and CLE Workshop on Nov. 27 from 9 a.m. to […]

Comments on 2018 Electronic Annual Reporting

Agency: State Water Resources Control Board Subject: 2018 Electronic Annual Reporting Letter excerpt:  We appreciate your efforts in convening the Division of […]

2018 Summary of Appellate Cases

ACWA’s  2018 Summary of Appellate Cases details court decisions in 2017-’18 that may be of interest to ACWA member agencies […]

November 2018 Federal Regulatory Issues Chart

ACWA’s November 2018 Federal Regulatory Chart, is now available. This chart details the status of federal regulatory issues being tracked by […]


Sorry, but only ACWA members have permission to view this content. Member login is required.

Bay-Delta Plan Update Toolkit

Sorry, but only ACWA members have permission to view this content. Member login is required.

ACWA 2018 Regulatory Summit Presentations

ACWA’s 2018 Regulatory Summit was held on Oct. 16, 2018 at the Hilton Arden-West in Sacramento. The theme of this […]

Comments on Low-Income Water Rate Assistance Program Implementation

Agency: State Water Resources Control Board Subject: Implementation of Low-Income Water Rate Assistance Program Letter excerpt:  The Association of California Water Agencies […]

Joint Comments On Making Water Conservation a California Way of Life: Primer

Agency: Department of Water Resources Subject: Making Water Conservation a California Way of Life: Primer of 2018 Legislation on Water […]

August 2018 Federal Regulatory Chart

Sorry, but only ACWA members have permission to view this content. Member login is required.

Toolkit Available for Supporting, Educating About Proposition 3

Sorry, but only ACWA members have permission to view this content. Member login is required.


California’s second annual Water Professionals Appreciation Week will kick off Oct. 6, highlighting the important role of water industry professionals […]

Suggested News

15 Articles prev next
ACWA Launches “California H2O: Flowing For the Future” Video Series to Promote California Water Industry

ACWA has developed the first three episodes of a new educational video series to help member agencies inform their customers, […]


COMMERCE – The Central Basin Municipal Water District is proud to announce that residents and businesses in our service area […]

Two CVWD projects selected to receive EPA federal loans

COACHELLA – Two Coachella Valley Water District (CVWD) stormwater projects have been selected to receive Environmental Protection Agency (EPA) federal […]

State Water Project Begins Year with 10 Percent Allocation

On Nov. 30, the California Department of Water Resources (DWR) announced an initial allocation on the State Water Project (SWP) […]

Award Winners on Display at ACWA’s 2018 Fall Conference in San Diego

SAN DIEGO – Today, the Association of California Water Agencies (ACWA) handed out awards in several categories to water agencies and individuals […]

ACWA Awards Graduate Scholarship for 2018-’19 Academic Year

SAN DIEGO – The Association of California Water Agencies (ACWA) today announced the winner of its 2018-’19 Stephen K. Hall Water […]

New PWD Water System Master Plan, Associated Fees Approved

PALMDALE – A new Water System Master Plan that projects infrastructure needs through 2030, including updated Capital Improvement and Water Supply […]

Central Basin Recognized for Excellence In Information Technology

COMMERCE – The Central Basin Municipal Water District has once again been recognized for information technology practices that excel in […]

EMWD Announces 2018 Water Champion Award Recipient

PERRIS — Eastern Municipal Water District (EMWD) today announced that Assemblywoman Anna Caballero was selected for its 2018 Water Champion […]

Operation FATFISH

A recent ACWA event jointly hosted by Region 2 and Region 4 vividly illustrated the value behind functional flows and […]

November/December Priority Issues Update

The November/December 2018 Priority Issues Update is now available online to members. The update is bullet-style summary of the latest […]

PWD, Partners Break Ground at Recharge Project Site

PALMDALE – Palmdale Water District (PWD) officials joined the City of Palmdale, California Department of Water Resources and other local […]

New Assistant General Manager Named for Elsinore Valley Municipal Water District

LAKE ELSINORE – Elsinore Valley Municipal Water District (EVMWD) named Brian Macy, P.E., seasoned water and engineering industry leader, as […]

Western’s Communications Programs Take Home Top Honors

RIVERSIDE – Western Municipal Water District (Western) received nine top honors from the Public Relations Society of America-Inland Empire Chapter […]


ROWLAND HEIGHTS– The Rowland Water District Board of Directors has released the details of its latest, comprehensive Strategic Plan, which […]