DWR's Tunnel Vision: Ignoring Science Won't Make It Go Away

Why does the Department of Water Resources’ draft Environmental Impact Report (DEIR) for the proposed Delta tunnel project refuse to consider any operational alternatives that increase flows into and through the Delta to protect salmon and the environment?   

After all, for more than a decade, State and federal agencies have repeatedly concluded, as the State Water Board concluded in 2009, that “[t]he best available science suggests that current flows are insufficient to protect public trust resources.”  The minimum Delta water quality and outflow requirements in the Bay-Delta Water Quality Control Plan have not been substantively updated since 1995, and the State Water Board has been working since 2008 to update those outdated and inadequate flow requirements that have caused an ecological crisis. In 2018, the Board released its Framework for completing the update of the Bay-Delta Plan’s water quality standards, which proposes to require increased Delta outflows and improve upstream reservoir storage and water temperature management, resulting in reduced water diversions from the Bay-Delta (on average 2 million acre feet per year).  And if that wasn’t enough, the State Water Board’s CEQA scoping comments for the Delta tunnel explicitly directed DWR to consider one or more operational alternatives that increase flows through the Delta, consistent with the State Water Board’s 2018 Framework

While there’s no debate that the construction of the proposed Delta tunnel would significantly impact Delta residents and communities for years on end, the impacts to fish and wildlife from a Delta tunnel project crucially depend on how the project would be operated: how much water would be diverted and when, and how much left for the environment.  When NRDC proposed a single tunnel portfolio alternative in 2013, a critical component was environmentally protective operations that reduced water diversions from the Delta in most years.  Operational criteria for existing and proposed new infrastructure, like the Delta tunnel, will be the difference between existence and extinction for many of our native fish species, including our native salmon runs and the thousands of jobs that depend on their health.

Yet inexplicably, DWR’s DEIR refuses to consider any operational alternatives.  Even worse, DWR’s proposed operations of the Delta tunnel are significantly less protective of the environment than the operations that the National Marine Fisheries Service and other agencies required for the proposed twin tunnel project only a few years ago (California WaterFix), as we explained in this letter to DWR last year.  As a result, all of the alternatives in the DEIR substantially increase water exports from the Delta on average by approximately 500,000 acre feet per year, including significant increases in water diversions in dry and critically dry years (200-300,000 acre feet per year), as the table below from the DEIR shows:

Because the project fails to include environmental protective operational criteria, the DEIR’s modeling (see pages ES-71 to ES-74) concludes that the Delta tunnel (and all alternatives) will reduce the survival of winter-run and spring-run salmon migrating through the Delta, reduce the abundance of Longfin Smelt, increase the number of Delta Smelt that are entrained and killed, and worsen ecological conditions in the estuary (including reducing Delta outflow in dry and critically dry years - see Table 5A-B3.3.4.4-D.).  The status quo in the Bay-Delta is awful for our native fish and wildlife, but the DEIR demonstrates that the Delta tunnel project – at least with the proposed operations – would make things in the Delta even worse.

And if that’s not enough, the DEIR excludes consideration of the effects of climate change in assessing whether the proposed project and alternatives will cause significant impacts under CEQA.  Instead, the CEQA analysis is based on observed hydrological conditions from 1922-2015 without accounting for the effects of climate change that have been documented and observed over the past century, including: increases in air and water temperatures, earlier runoff, increased frequency and magnitude of droughts, and sea level rise.   While the DEIR includes appendices that model the effects of the Delta tunnel with the anticipated effects of climate change in 2040, when the Delta tunnel could first be operational,

These longer-term analyses were performed outside of CEQA requirements to provide information about possible future environmental conditions once conveyance facilities are operational. Because these analyses are provided for informational purposes, no CEQA significance conclusions are presented for potential impacts, and no mitigation measures are recommended to reduce potential impacts.

(DEIR, Chapter 4 at 4-5 to 4-6).  This approach seems to clearly violate DWR’s 2018 Guidance on Climate Change Analysis and does not comply with CEQA. 

Ignoring the fact that increased flows into and through the Bay-Delta are needed to protect and restore the health of this imperiled ecosystem – and that the State Water Board’s 2018 Framework is a reasonably foreseeable update of the Bay-Delta Water Quality Control Plan that must be considered – is inconsistent with CEQA.  To be fair, the Delta tunnels DEIR isn’t the only CEQA document that refused to consider any operational alternatives to protect the environment.  In the coming weeks, we will highlight several other flawed environmental analyses for projects in the Bay-Delta, all of which are proposing to divert the same water – much of which won’t be available for diversion when the State Water Board finally adopts a scientifically credible update to Delta outflow other Delta water quality objectives in the Bay-Delta Water Quality Control Plan.

Like an ostrich sticking its head in the sand, the Delta Tunnel DEIR's attempt to simply ignore the fact that the salmon and other native species need more clean water flowing into and through the Delta won’t make the biological science go away. 

About the Authors

Doug Obegi

Director, California River Restoration, Water Division, Nature Program

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