Oregon Revised Statutes Water Resources: Irrigation, Drainage, Flood Control, Reclamation § 545.517

The contract provisions for the payment of construction charges to the United States may call for the payment of such interest, may provide for such installments and may provide for repayment of the principal at such times, as may be required by the federal laws and as may be agreed upon between the board and the Secretary of the Interior. If bonds of the district are issued and deposited for the purpose of securing payment of construction charges to the United States, the bonds may be of such denomination and may provide for the payment of such interest as may be required by the federal laws and as may be agreed upon between the board and the Secretary of the Interior.