California Code, Government Code - GOV § 16415

All money received by the State from the United States in pursuance of any act of Congress providing for the distribution and payment to states and territories of a fixed percentage of the money received by the United States from the land acquired in the State for flood control purposes shall be credited to the United States Flood Control Receipts Fund, which fund is continued in the State Treasury, and shall be disposed of, pursuant to the act of Congress, by the payment of the money to the several counties in which the flood control lands are situated.

The payments made to each county from the receipts of any given parcel of federal flood control land shall be in the proportion which the area of the parcel situated in the county bears to the total area of such parcel.