Water projects say modifications are necessary to meet health and safety needs, control salinity intrusion in the Delta, preserve cold water pool, and maintain adequate protections for fish and wildlife; No decision yet on temporary rock barriers in the Delta
The Department of Water Resources and the Bureau of Reclamation have submitted a request to the State Water Board, asking for modifications to the revised March 5 Temporary Urgency Change Petition order. These changes are being requested to allow for continued operation of the state and federal water projects to meet health and safety needs, lessen critical economic losses, control salt water intrusion into the Delta, preserve cold water pools in upstream reservoirs for fisheries, and maintain adequate protection for endangered and threatened fish and wildlife species, the letter states.
The current order allowed modifications for February and March; these modifications are being requested for April through September of 2015. The intent of the modifications are to continue to focus on conserving water in the upstream reservoirs to protect aquatic species, water quality, and water supplies, and to help meet fall Sacramento River temperature requirements.
The letter lists in detail the modifications being requested, which include modifications to the Net Delta Outflow Index, the Vernalis flow requirements, and the minimum Sacramento River flow requirements at Rio Vista, as well as moving the Western Delta salinity standard compliance point from Emmaton to Three Mile Slough and modifications to the Vernalis salinity requirements. The letter states that DWR and Reclamation have not made any decision yet on installing rock barriers in the Delta. If it is decided the rock barriers are necessary, a subsequent TUCP will be submitted.
The request also includes a revised and resubmitted request for approval of an intermediate export rate, intended to give the projects flexibility to capture increased natural and abandoned flows that might result from a sporadic storm event. The letter acknowledges that given the dry forecast, exercising this modification is unlikely.
“For clarity, this is a request for regulatory flexibility,” the letter states. “If a storm event creates hydrologic conditions that would allow for this modification to be implemented, Reclamation and DWR would consult with RTDOT to consider real-time conditions, including water quality and latest fisheries survey information. If consensus is obtained at RTDOT that any additional exports can be implemented without causing unreasonable harm to fish and wildlife, Reclamation or DWR would notify the State Water Resource Control Board Executive Director and seek final approval.”
The letter notes that the intermediate export rate was conditionally approved in the revised March 5, 2015 Order, but only applies when the the additional water deemed is necessary to meet minimum public health and safety needs. However, due to the severity of drought conditions and the limited amount of water that might be exported under this modification in the upcoming months, Reclamation and DWR say it would be ‘impractical to attempt to track this increment of water separately from other project deliveries.”
“The ‘urgent need’ described int he previous change requests continue to exist,” the letter states. “This TUCP request adds additional measures to help address critically low storage levels in San Luis Reservoir and DWR’s and Reclamation’s reservoirs north of the Delta and associated water supply needs of those reservoirs.”
The letter states that this action should also not have an unreasonable impact to fish and wildlife, and that they are seeking concurrence from the federal and state agencies that the actions are consistent with the endangered species regulations.
Legal users of water will not be injured by this action, the letter states. “Delta water quality objectives protective of municipal/industrial and agricultural uses remain in place and the proposed combination of outflows and export levels are expected to continue to provide water quality adequate to meet the needs of beneficial uses,” they say. “However, hydrologic conditions indicate that sufficient water may not be available in upstream reservoirs to maintain a cold water pool and also meet the Emmaton standard.”
“By conserving reservoir storage through the remainder of this year, providing protections for aquatic species, water quality and water supply, and thereby avoiding the severe consequences associated with depletion of reservoir capacity, the proposed changes are in the public interest,” the letter states.