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Independent Science Review Panel Finds Problems with Delta Tunnels Biological Opinion

(Science Geek Edition)
An analysis by an Independent Review Panel has been made public by the Delta Stewardship Council (DSC).
The panel was convened by the DSC Science Program to provide the National Marine Fisheries Service (NMFS), U.S. Fish and Wildlife Service, and California Department of Fish and Wildlife with an independent analysis of the scientific information used in the California WaterFix (CWF) Incidental Take Permit application.
“This report suggests that the biological opinion has flaws and that the Delta Tunnels will be terrible for Delta fish – those that live here year round as well as those just passing through on their way to and from the Pacific Ocean,” said Tim Stroshane, Policy Analyst for Restore the Delta. “I have always worried that while reverse flows on Old and Middle River may decrease, the Tunnels will create reverse flow effects into the Sacramento River system, with effects on fish that were not analyzed adequately from the beginning of the Tunnels proposal in 2012. I’m actually saddened to find those concerns confirmed by this Independent Review Panel report.”
Analysis Lacking
Overall, the panel found that impacts of the North Delta Diversion (Delta Tunnels) “…could potentially alter habitat availability by reducing the frequency and duration of tidal inundation of fish spawning and rearing habitats.” These impacts should be considered in the final version of the Biological Opinion being created by the National Marine Fisheries Service.
Among the findings by the Independent Review Panel are:
1. A lack of planning to “avoid, minimize, and mitigate the more significant effects” on migrating fish species, including salmon, steelhead, and sturgeon. “The Panel encourages the development of a comprehensive mitigation plan that takes into account the need for restoration actions that often take years to become fully beneficial.”
2. The Panel notes that the NMFS Biological Opinion made explicit that it would apply “institutional caution” and give the benefit of the doubt in scientific uncertainties (which abound) to salmon species, as opposed to water developers, when considering uncertainties in data, analytic methods, and results.
3. The Panel raises concerns over construction-related effects including “increased turbidity and chemical exposure throughout the Delta from 15,000 barge trips; creation of predation hot spots at construction barge landings; predation along the very long cofferdam wall; fish exposure to potentially stressful pile-driving noise; and prediction increases during construction at Clifton Court Forebay.”
4. Consistent with BDCP and CWF modeling in recent years, NMFS’s BO found that there will be a “significant reduction in overall survival [of Winter-Run Chinook Salmon] associated with” operations of the California WaterFix diversion facilities in the north Delta.
5. The Panel Summary says the analysis of the Delta Tunnels “…should have considered long-term changes in habitat quantity and quality associated with water removal from NDD [north Delta diversion] operations and the resulting effect on salmon distribution and access to habitats, as well as important habitat characteristics such as salinity, sedimentation, vegetation, water depth and velocity.”
6. The Panel also found that NMFS missed “four important hydrodynamic downstream effects of NDD operations that must be considered in the BiOps.” They missed Delta Cross Channel operations which will change when operation of the NDDs begin, which will affect when various Delta fish find their way into the Central Delta where they face much increased predation than they do in the Sacramento mainstem. The Biological Opinion also fails to address what effects reverse flows in the Sacramento will have on the fish.

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  • James Potter
    April 20, 2017, 11:38 pm

    It’s clear and evident that in order to convey water to the South from the Delta, the water to supply the Delta needs to be increased. Without an increased water supply created by more reservoirs the Tunnels will create reverse flows. Even with an increased water supply, the construction of the Tunnels alone, will still destroy the Delta. Improving the fish shield in the Clifton forebay, is a much simpler, and less expensive way to increase the amount of water conveyed to the South. Reservoirs South of the Delta would even be a better solution.

  • April 30, 2017, 7:01 am

    Castles made of sand melt into the sea …. eventually.