(2) Subsection (1) of this section applies only to cities with respect to watershed areas which are the subject of an agreement between the city and the United States or any department or agency thereof, which agreement authorizes such action by the city.
(3) Violation of an ordinance adopted by any city pursuant to this section is a Class C misdemeanor.
(4) After adoption of an ordinance pursuant to subsection (1) of this section, a city shall post the area with suitable signs setting forth the prohibition of access or the conditions of limited access imposed by the ordinance. Failure to post the area as required in this subsection shall be a defense in any prosecution under an ordinance adopted by any city under authority of this section. [Formerly 449.327; 2011 c.597 §198]