Section 31160 Of Article 4. Bonds From California Streets And Highways Code >> Division 17. >> Chapter 5. >> Article 4.

. Out of the proceeds derived from the sale of any such additional bonds there shall be set aside an amount of money sufficient to retire such outstanding bonds as may be thereafter presented for payment. Bonds of the new authorized issue may be delivered in part in exchange for a like principal amount of outstanding bonds of the original issue if the holders of the outstanding bonds to be exchanged consent thereto.