N.D. Cent. Code § 61-07-09
After adopting a plan of irrigation works, the board shall secure bids as provided in chapter 48-01.2. Contracts for the purchase of materials must be awarded to the lowest and best bidder. The person to whom a contract may be awarded shall furnish a bond with good and sufficient sureties, to be approved by the board, payable to such district for its use, in an amount at least equal to the contract price, conditioned for the faithful and complete performance of the contract. The work must be done under the direction and to the satisfaction of the engineer and must be approved by the board. This section does not apply in case of any contract between the district and the United States, or any department, bureau, or agency thereof, or with the state water commission.
N.D.C.C. § 61-07-09