Wat. Code, § 71699

No publicly owned utility shall commence to provide any water service for, on, or to any land within a municipal water district which is subject to (1) the lien of a bonded indebtedness incurred by the district for the purpose of providing a service similar to that which the utility proposes to provide or (2) a lien of an indebtedness arising under any contract between the district and the United States of America incurred or contracted by the district for the purpose of providing water service; provided, that a majority of the voters voting at an election within the district have approved the incurrence of the indebtedness and, provided further, that the district has water available and is ready, able, and willing to serve such land.

However, a publicly owned utility may commence to provide service, otherwise prohibited, upon either of the following conditions:

(a) In any portion of such a municipal water district proposed to be served by the publicly owned utility in which the total number of registered voters residing therein is less than 12, and in which the municipal water district (1) receives the written consent of at least a majority of the owners of real property holding at least a majority in value of the real property and (2) consents to the service by resolution.

(b) In any portion of such a municipal water district proposed to be served by the publicly owned utility in which the total number of registered voters residing therein is 12 or more, and in which at least a majority of the voters voting on the proposition shall have voted at a special municipal water district election to permit such service within that portion of the district. The election shall be called and held within that portion of the district in the same manner as an initiative measure pursuant to Section 71530.