When any watercourse or natural drainage line crosses the boundary line between two adjoining landowners and both parties desire to drain their land along such watercourse or natural drainage line, but are unable to agree as to the junction of the lines of drainage at such boundary line, the board of supervisors of the county in which said land is located shall have full power and authority upon the application of either party to hear and determine all questions arising between such parties after giving due notice to each of the time and place of such hearing, and may render such decision thereon as to said board shall seem just and equitable.
Iowa Code § 468.619
89 Acts, ch 126, §2
Referred to in §468.620