[Contracts for construction of works; advertisement; bids;

contractor's bond; supervision by engineer.] After adopting a plan for the construction of canals, reservoirs and works, the board of directors shall give notice, by publication thereof, not less than twenty days in a newspaper published in each of the counties into which any such irrigation district extends, provided a newspaper is published therein, and in such other newspapers as they may deem advisable, calling for bids for the construction of said work or any portion thereof; if less than the whole work is advertised, then the portion so advertised must be particularly described in such notice; said notice shall set forth that plans and specifications can be seen at the office of the board, and that the board will receive sealed proposals therefor and that the contract will be let to the lowest responsible bidder, stating the time and the place for opening the proposals, which at said time and place shall be opened in public, and as soon as convenient thereafter the board shall let said work, either in portions or as a whole, to the lowest responsible bidder, or they may reject any or all bids and readvertise for proposals or may proceed to construct the work under their own superintendence. Contracts for the purchase of material shall be awarded to the lowest responsible bidder. The person or persons to whom a contract may be awarded shall enter into a bond with good and sufficient sureties, to be approved by the board, payable to said district for its use, for not less than ten percent of the amount of the contract price, conditioned for the faithful performance of said contract. The work shall be done under the direction and to the satisfaction of the engineer in charge subject to the approval of the board.