Cal. Gov. Code § 25215.7

Whenever a person installs any facilities including, but not limited to, facilities for sewer or water service, and the board determines that it is necessary that those facilities be constructed so that they can be used for the benefit of property within a county service area other than the property of the person installing the facilities, and the facilities are dedicated to the public or become the property of the county or the county service area, the board may by contract agree to reimburse that person for the cost of the installation of those facilities. This contract may provide that the board may collect a reasonable fee or charge from any person using those facilities for the benefit of property not owned by the person who installed the facilities.