To store water you must first have it.

People also ridicule the delta tunnels that Brown is pushing. This is to get water from the Sacramento River to points south of the delta. Whether or not you believe in man caused global warming, the sea is rising. It has been measured daily in San Francisco Bay since the 1860's. This causes salt water to go ever further into the delta. When the salt water reaches Clifton Court Forebay the California Aqueduct will not have access to fresh water. This will be a disaster to the Southland and to agriculture in the central part of the Great Central Valley.

Increasing storage is not a bad idea (even if the best locations are already used), especially as global warming is reducing our natural storage... Snow.