Gov. Code, § 26478

The board may authorize or direct any county officer, employee or department to perform services for or in connection with the development, construction, maintenance or operation of any project and the cost of such services shall be a charge against the appropriate project fund.

The board shall not authorize, direct, or permit any county officer, employee or department to render any services for or in connection with any project or to incur any cost or expense for or in connection with or in aid of any project until funds are available either from the proceeds of the sale of bonds authorized for the project or from the revenues thereof for the payment of such cost or expense and all costs and expenses incurred by the county or by any officer, employees or department thereof for or in connection with or in aid of any project constitute a charge against the appropriate project and shall be paid from the appropriate fund of such project in the same manner as other costs and expenses incurred in connection with such project are paid.