Idaho Code § 18-3908
Any person who runs water either by flooding or sprinkler irrigation across any public highway, road or street, without first constructing a good and sufficient ditch or ditches to convey the same, or who fails to bridge such ditch or ditches, or to keep such bridge or ditches in good repair, or to ensure that the flow from the sprinkler does not flood the public highway, road or street and all persons, companies or corporations who suffer any water used by them for the purpose of irrigation, or any other purposes, to flow into or upon any public highway, road or street, in any other manner than that authorized by law, are guilty of an infraction on the first offense, and shall be guilty of a misdemeanor for each offense thereafter per calendar year, and upon conviction thereof shall be fined fifty dollars ($50.00), and for a second offense, double said fine and costs; and it is hereby made the duty of all road supervisors, constables and marshals, to make complaint before the proper court, for violations of this section, whenever notified or having knowledge thereof. A person may not be charged under the provisions of this chapter if the flooding from a sprinkler or other water conveyance system is a result of mechanical failure, wind or other climatic condition, or other circumstances outside of the control of the person.
Idaho Code § 18-3908