Chapter 6. Changes In Organization of California Water Code >> Division 31. >> Chapter 6.

Any territory annexed to, or detached from, a member public entity, upon completion of the annexation or detachment, shall be deemed annexed to, or detached from, the agency.

(a) A public entity identified in Section 81305 that is not a member at the time the agency is formed pursuant to Section 81328 may thereafter join the agency, with the approval of the board of the agency and subject to those terms and conditions that the board determines are necessary to ensure that the new member pays an equitable share of the costs previously incurred by the agency.
  (b) The new member shall appoint one director and, for the purposes of this division, the new member shall be subject to the water delivery amounts described in Section 81460 that apply to that new member.

San Francisco may become a member of the agency pursuant to Section 81456.

Not later than 10 days after the date on which any new member is admitted, the agency shall notify in writing the Secretary of State with regard to the name of the new member and the date of its admission.