I live on the Delta and am a retired mechanical engineer and hold a Master’s degree in business administration. I have an idea on California’s water situation that I believe merits serious review. I call it The California Delta Fresh Water Assurance Barrier.
This idea is not new as similar proposals go back more than 100 years. However, California was a dramatically different place then. I believe the idea’s time has now come.
Currently, vast amounts of California’s precious fresh water flow daily through the Carquinez Strait and then to the sea....lost forever. California needs to capture this vital resource.
Let’s build a permanent barrier across the shallow area of the Carquinez Strait between Benicia and Vallejo. This would essentially be a low dam, perhaps only 10-20 feet higher than the maximum high tide level of the Bay. East of the barrier all water would be fresh and to the west all salt water.
There would be large, modern and efficient fish ladders to facilitate unfettered fish migration across this low barrier. Locks would assist ship and recreational boat traffic.
The fresh water behind the barrier would be kept at a continuous high tide level year round, vastly increasing the fresh water reserve held in the Delta Fresh Water Reserve.
The barrier would eliminate all salt water incursion concerns related to possible levee failure and-or predicted future sea level change scenarios. There would be no need for contentious diversion tunnels or canals since fresh water integrity and supply would be assured at all times, regardless of levee failure or sea level rise.
The Sacramento River and its inflow tributaries would continue to flow unfettered into and through the entire Delta, flushing and preserving water quality and thus mitigating any impact on the ecology of the Delta.
The existing export pumps at Byron would run at full capacity at practically all times since all the water now lost to the sea would be saved and available for storage in existing and new reservoirs south of the Delta. Any surplus water would be spilled off to the Bay.
Vastly improved modern fish screens would be installed to dramatically reduce fish loss at the pumps. Optionally, these pumps could be fed by tunnels with their intakes near the barrier dam at Carquinez, thus restoring the Delta’s original flow characteristics.
During wet years, spillways at the barrier dam would allow any excess runoff water in the Delta Reserve to flow harmlessly into the Bay and out to sea preventing flooding.
The Bay’s vast tidal flows through the Golden Gate flush the South Bay which has no significant fresh water inflows. The much smaller North Bay would become similar.
California’s expanding population and its enormous contribution to our nation’s gross national product demands that we not waste our most vital resource – fresh water.
This suggested approach dovetails nicely with the existing export infrastructure and future upstream storage enhancements now under discussion.
We should fully explore this alternative.
John Anderson, Isleton, Calif.