Streets and Highways Code § 950
CHAPTER 2. Powers and Duties of Boards of Supervisors
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.