CONTRA COSTA COUNTY --
The California Department of Water Resources has begun erecting a 750-foot wide rock wall across a Delta Channel near Jersey Island to keep tidal salt water from flowing into the Delta.
The $40 million temporary structure was needed because of the drought emergency. Normally salt intrusion, which contaminates irrigation and drinking water, is controlled with releases from state reservoirs.
But reservoir levels are low and there is no snow pack this year to replenish them.
"By putting this barrier in place, we prevent that exchange of saline water up into this part of the Delta," said DWR Drought Manager Bill Croyle.
Critics say the state didn't need to do expensive fixes in the Delta if they had managed water levels better by preventing so much water from being shipped south through the state's aqueduct system.
"We really resent that the state has to manage the system in a way that they tinker in the Delta and pit one side of the Delta against the other," said Barbara Barrigan-Parrilla, Executive Director of Restore the Delta.
Locals complain that the barrier would also prevent outflows from the Delta and that backing up water upstream of the barrier would harm levees. A major channel for boaters will also be cutoff.
"You're going to force all that business north, thereby crippling our already fragile economy," said Tony Berzinias, President of the Bethel Island Improvement District.
But DWR water managers say the construction of the barrier was a strategy of last resort.
"It was the last thing that we wanted to do, partially for the expense, partially due to the impacts to the recreational community, and partially to the impacts to the habitat as well," said Paul Marshall, Chief of DWR's Bay-Delta Office.
The barrier is a temporary emergency solution and will be taken down in November, when there may be more freshwater flowing into the Delta. But if there is a fifth year of drought, it could be put back up.