California Code, Water Code - WAT § 1745.05

(a) Water stored by the water supplier and water made available from either of the following sources may be transferred by the water supplier pursuant to Section 1745.04:

(b) The amount of water made available by land fallowing may not exceed 20 percent of the water that would have been applied or stored by the water supplier in the absence of any contract entered into pursuant to this article in any given hydrological year, unless the agency approves, following reasonable notice and a public hearing, a larger percentage.