Whenever, upon the creation of a district any municipality therein or any county in which the district is located which has theretofore authorized or incurred a bonded indebtedness for any work or improvement for which the district may incur a bonded debt pursuant to this part, and such municipality or such county thereafter sells such bonds or any portion thereof, the proceeds of the sale may, upon the order of the appropriate board of supervisors or city council, be paid by the custodian into the treasury of the district and shall be applied by the board, exclusively to the purposes and objects for which the bonds were authorized by the municipal corporation or the county issuing them.