The board may authorize the temporary transfer of cash balances in any fund (except moneys in any fund which the district is required to set aside for the payment of bonds, notes or other evidence of indebtedness and the interest thereon) to any other fund; and the amount so transferred shall be repaid as soon as moneys are available in the fund to which such transfer has been made. Transfers of funds within, or revision of, a budget adopted by the district, whether before or after the incurring of a bonded indebtedness, may be made by appropriate act of the board at a regular or special meeting.