California Code, Water Code - WAT § 8706.5

Any activity that does or may interfere with, obstruct the performance, maintenance, or operation of, or otherwise adversely affect facilities of the State Plan of Flood Control, designated floodways, or streams that are regulated by the board constitutes a public nuisance, and the board may commence and maintain a suit in the name of the people of the state for the prevention or abatement of that nuisance.