Iowa Code § 468.529: Certificates and bonds.

The board of trustees of any district shall have the same power to issue improvement certificates and levee and drainage bonds under the same conditions and with like tenor and effect as is provided by subchapter I, parts 1 through 5, for such issuance by the board of supervisors, except that in case of the issue of levee or drainage bonds, the same shall be approved by a judge of the district court in and for the county or counties in which such district lies, which approval shall be printed upon such bonds before the same are negotiated.