Cal. Water Code § 71695

A district may construct works along and across any stream of water, watercourse, street, avenue, highway, canal, ditch, or flume, or across any railway which the route of the works may intersect or cross. Such works shall be constructed in such manner as to afford security for life and property, and the district shall restore the crossings and intersections to their former state as near as may be, or in a manner so as not to have impaired unnecessarily their usefulness.