Cal. Pub. Util. Code § 10102

A municipal corporation exercising its rights under this article shall restore the road, street, alley, avenue, highway, canal, ditch, or flume so used to its former state of usefulness as nearly as may be, and shall locate its use so as to interfere as little as possible with other existing uses of a road, street, alley, avenue, highway, canal, ditch, or flume.