Oregon Revised Statutes Public Health and Safety § 454.245

(1) The governing body of the municipality may determine the maturities and tenor of the bonds issued under ORS 454.235. However, the bonds shall be serial in character in accordance with present or future provisions of law or the charter. They shall be payable in not to exceed 40 years from the date of issuance thereof, and shall be sold at a price to net the municipality not less than the par value thereof with accrued interest. They shall bear interest at not to exceed six percent per annum payable semiannually.

(2) The amount of any bonds issued under ORS 454.205 to 454.255 shall not be within any limitation of indebtedness fixed by law or charter, but shall be in addition thereto.