The board of directors of a water resource district shall estimate expenses of the district and transmit them to the board of county commissioners according to section 61-16.1-06. The board of county commissioners may, by resolution, levy and authorize the county auditor to extend upon the county or portion of the county in the district a tax not exceeding four mills on each dollar of taxable valuation in the county or portion of the county in the district.
N.D.C.C. § 57-15-26.6