Cal. Pub. Res. Code § 7535

If a reclamation district is organized in any county, the board of supervisors of each county in which any portion of the lands of the district are located, upon the application of any interested party, shall direct the auditor and treasurer to set apart from the county swamp-land fund all money received in payment of principal and interest on the lands within the district, as a fund to the credit of the district, after deducting any money previously expended from the swamp-land fund for the benefit of land within the district. The money in the district fund shall be paid out only for the purpose of reclaiming land within the district, or to the owners of such land after reclamation, as provided by law. All money paid in upon these lands and diverted to the use and benefit of other lands shall be replaced out of the first receipts from the land so benefited.