Idaho Code § 40-1406
The highway commissioners of a county-wide highway district shall exercise all of the powers and duties provided in chapter 13, title 40, Idaho Code, and are empowered to make highway ad valorem tax levies as provided by chapter 8, title 40, Idaho Code. Only one (1) county-wide highway district shall be operative within a county where the electorate has voted affirmatively for the formation of a county-wide highway district. The district shall specifically be responsible for all county secondary and city highways and is hereby recognized as a body politic of this state. Notwithstanding any other provision of Idaho Code, the highway district may operate and expand an established public van and carpooling program, rideshare platform, or park-and-ride facility. No city included within a county-wide highway district shall maintain or supervise any city highways or levy any ad valorem taxes for the construction, repair or maintenance of city highways. No highway district included within a county-wide highway district shall maintain any secondary highways or levy any ad valorem taxes for the construction, repair or maintenance of highways. Wherever any provisions of the existing laws of the state of Idaho are in conflict with the provisions of this chapter, the provisions of this chapter shall control and supersede all such laws. However, within the limits of any city, the city may expend city funds for the placement, care and removal of trees, shrubs, grass, and other plants that are located within the rights-of-way of any highway of the county-wide highway district.
The commissioners of a county-wide highway district may pass ordinances and rules and make all regulations, not repugnant to law, as necessary, for carrying into effect or discharging all powers and duties conferred to a county-wide highway district pursuant to this chapter and chapter 13, title 40, Idaho Code. All ordinances created or passed by the commissioners of a county-wide highway district shall require the affirmative vote of two-thirds (2/3) of the members of the full county-wide highway district commission. The style of all ordinances shall be: "BE IT ORDAINED by the board of highway district commissioners of (......) County, Idaho." All ordinances passed shall, before they take effect and within one (1) month after they are passed, be published in at least one (1) issue of a newspaper published in the county or, if no paper be published in the county, then in some paper having general circulation therein. After such publication and before its effective date, such proposed ordinance shall not thereafter be amended wherein the amendment shall impose terms, conditions or privileges less favorable to the county-wide highway district than the proposed ordinance as published; but amendment favorable to the county-wide highway district may be made at any time and after publication. All ordinances passed pursuant to this section by the board of county-wide highway district commissioners may be proved by a certificate of the secretary of the county-wide highway district under the seal of the board of the county-wide highway district commissioners and shall be read and received in evidence in all courts and administrative proceedings without further proof. If ordinances duly passed are printed or published in book or pamphlet form by authority of the county-wide highway district commissioners, the printed or published book or pamphlet shall also be read and received in evidence in all courts and administrative proceedings without further proof. The commissioners of the county-wide highway district may enforce such ordinances by all appropriate administrative or judicial proceedings.
Idaho Code § 40-1406