Bay Delta Plan calls for 40% of unimpaired flow on the Tuolumne and other rivers

By Peter Drekmeier, TRT Policy Director

After decades of degradation due to inadequate freshwater inflows, the State is poised to take action to provide relief to the San Francisco Bay-Delta and rivers that feed it.

On September 15, the State Water Board proposed revisions to the Bay Delta Water Quality Control Plan aimed at updating minimum flow releases for the San Joaquin River and its major tributaries in order to protect fish and wildlife and control salt in the southern Delta.

The new Plan calls for 40% of unimpaired flow (what would naturally flow down our rivers) between February and June on the lower San Joaquin, Stanislaus, Tuolumne and Merced Rivers.  Currently, the three tributaries respectively see about 40%, 21% and 25% of their natural flow enter the San Joaquin.  Flows could range from 30-50% depending on how successful non-flow measures (such as habitat restoration) are at reaching established goals and objectives.

Higher flows will improve the ability of salmon and other fish to migrate to and from their natal streams to the ocean, reduce the concentration of river pollutants, and lower water temperatures.  Flows also should be adequate to inundate floodplains, which serve as critical rearing habitat for juvenile fish.


Historically, populations of spawning salmon exceeded 400,000 fish in these rivers, but in many recent years that figure has plummeted to just a few thousand.  California’s salmon population was so low in 2008 and 2009 that the commercial fishing season had to be cancelled, resulting in the loss of more than 2,200 jobs and $255 million in annual revenue.  Meanwhile, steelhead trout are protected under the Endangered Species Act.

A flow criteria report released by the State Water Board in 2010 determined that approximately 60% of natural flow between February and June would be fully protective of fish and wildlife in the San Joaquin Basin.  In 2013, the California Department of Fish and Wildlife also determined that 50-60% of natural flow should remain instream to protect and restore salmon and the health of our rivers.

The Bay-Delta forms the largest estuary on the West Coast, providing habitat for more than 500 species of wildlife.  It serves as a major stopover on the Pacific Flyway and as a migration pathway for salmon, steelhead and sturgeon.  Once a Garden of Eden, the estuary is now in desperate need of help.  The Bay Delta Plan is a once-in-a-generation opportunity to correct decades of mismanagement.

Through better management of snowmelt, implementation of water efficient technologies and irrigation practices, and replacing lower-value, water-intensive crops with higher-value, water-efficient crops, we could grow more food with less water.


A good example of how successful water conservation can be is right here in the Bay Area.  Between 2006 and 2016, the 2.6 million people who depend on the Tuolumne River via the Hetch Hetchy Water System decreased their water usage by 30%.  By using our precious water more efficiently, we can continue to enjoy a thriving economy while restoring the rivers and waterways that make California such a special place to live and visit.

Your voice in support of higher flows on these rivers will help to push the State Water Board to do the right thing.

Here’s how you can help:

1) Sign the petition and forward it to others.

2) Submit a comment letter to the State Water Board (email for letter writing tips).  Please address your letter as follows, and submit it by email, fax or standard mail.  For emails, it’s best to send your comments in pdf format.  Comments are due by noon on March 17, 2017.

Jeanine Townsend, Clerk of the Board
State Water Resources Control Board
1001 I Street, 24th Floor
Sacramento, CA 95814-0100

Fax: (916) 341-5620

Include in the subject line: “Comment Letter – 2016 Bay Delta Plan Amendment & SED”

You can also forward your comments to your state legislators.  Contact information is available here.

3) Attend one of our Information Sessions

Tuesday, April 10 – 6:00 p.m.
San Francisco Public Library, 100 Larkin St, San Francisco, CA 94102

Wednesday, April 18 – 7:00 p.m.
Peninsula Conservation Center, 3921 E Bayshore Rd, Palo Alto, CA 94303

4) To get more involved in the campaign, please email

State Water Board Resources

State Water Board Fact Sheet
Summary of Proposed Updates to the Bay Delta Water Quality Control Plan
SED Executive Summary
Bay Delta Plan website
Development of Flow Criteria for the Sacramento-San Joaquin Delta Ecosystem

Articles, Editorials & Reports

TRT video about the Bay Delta Plan
TRT analysis of SFPUC’s Socioeconomic Study
TRT critique of SFPUC brief
How to revive a dying delta (OpEd in the San Francisco Chronicle)
We must work together to balance a limited resource – water (OpEd in the Modesto Bee)
A Cal Alum’s Recipe for More Tuolumne River Salmon: Add Water (California Magazine)
Why are we sending precious water downstream for fish in the middle of a drought? Here’s why. (Los Angeles Times Editorial)
Regulators propose leaving more water in California’s rivers (San Francisco Chronicle)
San Francisco Bay: The Freshwater-Starved Estuary (A report from The Bay Institute)
What will it take to make San Joaquin River system healthy again? (OpEd in the Sacramento Bee)
Seeking a better way to share rivers among people, wildlife (OpEd in the Sacramento Bee)
San Francisco Bay Estuary needs more fresh water (OpEd in the San Jose Mercury News)
Allocating San Joaquin River Water to the Environment Shows Promise (OpEd in Water Deeply)
A Delta Renewed: A Guide to Science-Based Ecological Restoration in the Sacramento-San Joaquin Delta (A report from the San Francisco Estuary Institute)
California can revive San Francisco Bay-Delta estuary (OpEd in the San Jose Mercury News)