(1) It shall be the duty of every person who owns or controls any dam or other obstruction across any watercourse within the jurisdiction of the state, where such impounded water is returned to the bed of the stream, to make such provision as may be necessary to ensure that sufficient water is returned at all times to the bed of the stream or river below such dam or obstruction as to preserve fish life in such stream. This section shall not apply under conditions of unusual circumstances resulting from natural causes which make the fulfillment impracticable. Every person owning or controlling such dam shall open and close gates or locks at a rate slow enough to protect the water below from a sudden flushing or sudden decrease in water flow which would be detrimental to the fish and their habitat.
(2) The commission shall have supervision over the enforcement of this section and shall investigate all complaints made under this section.
(3) Any person, firm, or corporation violating this section shall be guilty of a Class V misdemeanor.