California Code, Public Resources Code - PRC § 3965

(a) He or she shall give a notice of the intent to cross a stream to the clerk or the secretary of each city or district owning or operating a domestic water supply whose clarity is likely to be affected by the crossing operation.

(b) The notice shall be given at least seven days in advance of the date that he or she expects to cross the stream with the dredger.

(c) Upon the expiration of the notice, the operator may, during the following 48 hours, conduct the dredger across the stream even though some turbidity may be caused by the crossing operation.

(d) After crossing the stream, the operator shall comply with subdivision (b) of Section 3964.