Smaller Doesn’t Mean Cheaper
Trimmed-Down Delta Tunnel Would Still Be Costly, State Agency Contends
California Natural Resources Agency officials say that slashing the capacity of a Delta tunnel system proposed under the Bay Delta Conservation (BDCP) to permit north state supplies to bypass the troubled estuary while being conveyed would still cost many billions of dollars to maintain.
The idea to drastically scale down the Delta tunnel project’s capacity from 9,000 cubic feet per second as proposed by Governor Brown’s administration to 3,000 acre-feet was launched earlier this year and has mostly been promoted by the environmental community.
The tunnel system would convey north state water destined for Central Valley Project and State Water Project users from south of Sacramento to federal and state water export pumps northwest of Tracy.
State officials say that while the BDCP environmental analysis is not yet complete, the Department of Water Resources has found that a tunnel which is one third as large is in no way one third of the construction and maintenance costs.
It would also continue reliance upon the same aging pumping facilities in the south Delta that are of concern to the environmental organizations themselves. And it doesn’t free up nearly the necessary funds to replace the lost water supplies.
The cost of a smaller tunnel would outweigh its benefits and would not eliminate a third of necessary Delta improvements. New power delivery systems, similar land acquisition needs and comparable costs for project construction management and design would still be required.
“A larger, well-managed facility can ensure large water deliveries in wet months and that means our reservoirs get filled, making our water supplies more reliable,” state officials said.
With a smaller facility, building additional water storage south of the Delta would not help to solve the resulting problem of reduced water supplies of some 500,000 acre-feet annually on average.
While there can be differing perspectives on the right Delta solution, there appears to be a consensus that California needs a “portfolio” plan that includes local and regional water investments as well as improvements in the Delta, the DWR contends.