Will California Restore the Lower San Joaquin River and its Salmon?

From their headwaters in the Sierra Nevada mountains, the Merced, Tuolumne and Stanislaus rivers were historically wild, teeming with salmon that sustained native Americans, early settlers, and abundant wildlife.  These rivers join the lower San Joaquin River and flow into the Bay-Delta, one of the two main arteries that sustain the heart of the West Coast’s largest estuary.  But for too long, California has allowed farmers and cities to divert massive amounts of water from the rivers that run through the heart of California’s San Joaquin Valley, leaving only a fraction of the natural flow in these rivers in the winter and spring months. 

map of San Joaquin River basin

Decades of dam building, water diversions, and flood protection projects on these rivers have resulted in the vast majority of their flow being diverted each year.  This has degraded water quality and has devastated the fish and wildlife -- and people, like sport and commercial salmon fishermen -- that depend on their health.  Historically, hundreds of thousands of salmon returned each year to spawn in these rivers, but in recent years only a few thousand salmon have returned.  Despite state and federal laws that set goals to “double” salmon populations to approximately 78,000 salmon returning each year, salmon populations have continued to decline in the San Joaquin basin.

The scientific information is clear that reduced flows, as a result of diverting most of the water from these rivers, is the primary (but not sole) cause of the continued decline, and that more flows are needed to restore salmon, the health of these rivers, and the health of the Bay-Delta estuary. 

This summer, the State Water Resources Control Board will establish new flow standards to protect salmon and fisheries in the Lower San Joaquin River and the three tributaries.  The Board’s draft report concludes that about 35% of the natural flow should remain in the rivers, allowing more than 65% to be diverted.  Yet the scientific information shows that salmon are unlikely to recover at those flow levels, which are only slightly better than current flow levels. 

We can – and must -- do better than 35% for San Joaquin salmon to recover and achieve the state and federal salmon doubling goal. 

Diverting 65% of the Flow Won’t Restore California’s Magnificent Salmon

Scientists and fishery managers with the California Department of Fish and Wildlife, the State Water Resources Control Board, U.S. Fish and Wildlife Service, and The Bay Institute, as well as independent scientific peer reviews and other conservation and fishing groups, have recognized that current flows are inadequate.  For instance, in 2010, the State Water Resources Control Board concluded that the best available science showed that 60% of the natural flows should remain in the river in the spring months in order to achieve the salmon doubling requirement of state law and protect public trust resources (this was a non-binding conclusion).  The California Department of Fish and Wildlife has also concluded that much higher spring flows in these tributaries and the lower San Joaquin River are necessary to recover salmon and achieve the salmon doubling requirement.  Allowing the diversion of 65% of the water from would increase diversions on the Stanislaus River and isn’t even enough to meet minimum requirements under the Endangered Species Act on the Stanislaus River; if these flows are lower than what’s needed to avoid potential extinction, they obviously will not lead to recovery and salmon doubling.  And independent scientific peer reviews of the Board's technical report last year endorsed the scientific analysis showing that higher flows are necessary to recover salmon and recommended consideration of higher flows than 60%, which is the upper end of the range that the State Water Resources Control Board is considering.

We Can Maintain Healthy Agricultural Economy and Healthy Rivers

The Board’s draft analysis shows that reducing diversions to increase river flows will still result in a robust agricultural economy; for instance, the Board found that allowing 40% of the flow down the river would result in a 1.5% reduction in agricultural revenue in the region.  And this is likely a worst case scenario, as the Board’s analysis ignores the potential to increase agricultural water use efficiency to allow farmers to grow “more crop per drop” and increase profits, as well as water transfers between farmers and downstream exporters that could potentially help fund these improvements. 

Increasing Flows in the River Benefits Lots of People, Too

Improving flows and restoring salmon has huge benefits for salmon fishermen, tackle shops, charter boats, fishing guides, and the thousands of jobs that depend on a healthy salmon fishery.  Improved flows would improve water quality for Delta farmers and for cities and farms that get water exported from the Delta, and it is critical to restoring the health of the Delta.  Allowing 65% of the water to be diverted in the basin leaves only a third for the rest of us. 

Will California Restore the Health of the Low San Joaquin River and its Salmon?

The science is clear that more flows are needed than 35%, but the State Board is under pressure to adopt these weaker flow requirements despite the strong scientific evidence.  In the coming weeks, fishermen, farmers, conservation groups, boaters, birdwatchers, scientists, and all of us will have a chance to tell the State Water Resources Control Board to do better to help ensure the future of California’s salmon.  We can and should do better than 35%: is a third of a river really healthy?  I hope you’ll join us in urging the Board to do better.

For more information or to get involved, visit SalmonAid's petition to the State Water Resources Control Board.

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