Bonds issued pursuant to this chapter for facilities for delivery primarily of agricultural water supplies, in accordance with the provisions of any of the improvement acts mentioned in this chapter, may extend over a period not exceeding 24 years from the 2nd day of January next succeeding the next September 1st following their date and may provide that the first maturity date shall be the 2nd day of January, three years succeeding the next September 1st following their date and shall be paid in equal annual installments on January 2nd thereafter until the whole principal amount with accrued interest is paid.