Cal. Pub. Util. Code § 10208

The permission shall state the time for which it is given, which shall not exceed two years, and describe the work or improvement for which it is given, and shall require the permittee to maintain the work or improvement during the term of the permission, and to make all necessary repairs thereto during such term, and to furnish gas or water, as the case may be, to all lands assessed to pay all or any part of the costs and expenses of the work or improvement.