(1) Said owners shall submit such agreement to the board of county commissioners of the county wherein the major part of the lands proposed to be included in such district may be situated and shall submit therewith a plat of the land giving a general description of the same, and the said board of county commissioners as soon thereafter as may be practicable shall carefully consider all questions involved and shall make a personal inspection of the land proposed to be included in said voluntary district or may employ some competent engineer or surveyor to examine and report to said board on the same, and the expense of such surveyor or engineer, including any expense that the board of county commissioners may incur in the examination of such project, shall be paid by the parties to such voluntary agreement, and the board of county commissioners may require a deposit to be made with the county treasurer of the county to protect the county against such expense.

(2) If such board of county commissioners is satisfied that the plan proposed is practicable and will be conducive to the public health, convenience, utility, or welfare and that the agreement submitted is fair and equitable in all respects considering the benefits which the respective lands will receive from such voluntary drainage system, then the board of county commissioners shall enter an order upon their records approving such agreement and shall file the same with the accompanying plat in the office of the county clerk and recorder of said county. If such district extends into more than one county, a certified copy of the agreement and plat, together with a certified copy of the said order of the board of county commissioners, shall be filed by the parties to such agreement with the county clerk and recorder of such other counties, and thereupon the said drainage district shall be fully organized and established and have all the powers of drainage districts. The directors so named in said agreement shall then possess all the powers and proceed in like manner as before designated in the case of directors of districts organized by petition, and the agreement provided for in this article shall constitute a charter of authority of such voluntary district, and all lands subscribed to and voluntarily included in said district shall be considered as a unit or but one tract of land in the determination of any question or right or duty as between said voluntary district and any lands outside thereof, whether lying above, below, or adjacent to said district.