A water resource board may grant a reasonable extension of time for the completion of any contract. If a board reasonably believes the work required under a contract will not be completed by the agreed upon deadline, the board may relet any unfinished portion to the lowest responsible bidder, and shall take security as before. The cost of completing the unfinished portions over and above the contract price, and the expense of notices and reletting, must be collected by the board from the parties first contracting. The board may not terminate a contract without giving five days’ notice to the contractor, provided the contractor may be found or has a known place of residence in the county. The notice may be given to the contractor personally or may be left at the contractor’s place of residence.