Okla. Stat. tit. 63, § 63-4219: Nighttime speed limit

It shall be unlawful for any person to operate any vessel upon

the waters of this state which are under the jurisdiction of the

Grand River Dam Authority (GRDA), between the hours of one-half hour

after sunset and one-half hour before sunrise at any speed in excess

of thirty-five (35) miles per hour. Any person violating the

provisions of this section shall be guilty of a misdemeanor and

shall be punishable by a fine of not less than Fifty Dollars

($50.00) nor more than Two Hundred Fifty Dollars ($250.00).