Boards of supervisors shall have general supervision, management, and control of the county highways.

The board of supervisors may lay out, acquire, construct, and maintain any section or portion of any street or highway within the county as a freeway or expressway and may make any existing street or highway a freeway or expressway.

Boards of supervisors may close any street or highway within their jurisdiction at or near the point of its intersection with any freeway, or may make provision for carrying such street or highway over, under, or to a connection with the freeway, and may do any and all work on such street or highway as is necessary therefor.

No public highway shall be converted into a freeway except with the consent of the owners of abutting lands or the purchase or condemnation of their right of access thereto.

Before taking any action authorized by Section 941.2 affecting any state highway, such action must be approved by the Department of Public Works.

If the boundary line between two adjacent counties lies within a county highway, the boards of supervisors of the affected counties may, by agreement, provide for the improvement, maintenance, construction, or reconstruction of all or part of the highway by either or both counties, and each county may expend funds available to it for the improvements and maintenance of county highways as necessary for its performance of the agreement.

Such boards may enact and enforce ordinances and regulations for the construction, improvement or maintenance of county highways, and for the protection, supervision, management, control, or use of such highways. Any such board may by a four-fifths vote of all its members let county equipment used in the maintenance and construction of county roads, when such equipment is not in use upon the roads under the jurisdiction of the board, and may charge for the use thereof a rental, and arrange the basis of compensation, in keeping with the general conditions prevailing in the county in which the transaction is made.

The board of supervisors may restrict the use of, or close, any county highway whenever the board considers such closing or restriction of use necessary:

No liability shall attach to the county, or to the board of supervisors, for the restriction of use, or closing, of any county highway for the above public purposes.

This section does not constitute a change in, but is declaratory of, the pre-existing law.

The board of supervisors may delegate the powers contained in Section 942.5 to the county road commissioner.

Such board may:

No bonded indebtedness shall be incurred for any purpose specified in section 943 until after the question of the issue of bonds therefor has been submitted to the qualified electors of the county, at the next general election or at a special election called for that purpose, and two-thirds of the electors of the county voting at such election have voted in favor of issuing such bonds. The election shall be called and held and the bonds, if authorized, shall be issued, sold, and made payable as prescribed by law.

Such boards may expend from the county general fund the moneys necessary to pay the whole or any part of the cost of the improvement of any highway lying within any city in the county, whenever any real property belonging to the county and used for public purposes is included within the assessment district formed to pay for any such improvement. Such expenditures shall not exceed the amount which, but for such public ownership and use, would be properly chargeable to and assessed against such real property under the provisions of the law governing such improvement.

No liability shall be created against the county in connection with any such improvement conducted by a city unless the board, by resolution, determines and declares the amount to be expended and directs that such sum be set apart and reserved out of any moneys available for such purpose in the general fund of the county, to be used exclusively for paying the expense of such improvement.

Every instrument or judgment which constitutes evidence of title to a right of way, or incident thereto, in relation to county highways shall particularly describe the lands included in such right of way or incident.

The board of supervisors of each county shall cause to be recorded with the county recorder, in relation to every county highway within the county, proper evidences of title to every right-of-way, and all incidents thereto. The board of supervisors may, by ordinance, delegate this duty to a county officer or employee.

In cases of acquisitions by conveyance or condemnation, the property or incidents conveyed or condemned shall be particularly described in the instruments recorded.

The board of supervisors may plant shade and ornamental trees on the county highways, and provide for their care. The cost of planting and caring for such trees may be paid from the county general fund.

The board may also encourage, under such regulations as it adopts, the planting and preservation of shade and ornamental trees on the county highways, and may pay a sum not exceeding one dollar to any person planting and cultivating a living tree, payment to be made when the tree is four years of age.

For the purpose of sprinkling county highways with oil or water, the board of supervisors may erect or maintain waterworks, tanks or reservoirs, and may purchase or lease real or personal property therefor.

The board may charge the cost of erecting or maintaining such waterworks, tanks or reservoirs and of such sprinkling to the county general fund, the road fund, or the district fund of any district benefited.

Such board shall cause properly inscribed guideposts to be erected and maintained at all county highway crossings and forks lying outside of any city.