Before adopting or rejecting any bid filed under the provisions of this chapter, the governing body shall require the engineer for the municipality to make a careful and detailed statement of the estimated cost of the work for which proposals were advertised under section 40-22-19. The governing body may not award the contract to any bidder if the engineer's estimate prepared pursuant to this section exceeds the engineer's estimate of the cost of the work prepared pursuant to subsection 1 of section 40-22-10 by forty percent or more.
N.D.C.C. § 40-22-29