Iowa Code § 468.109
Whenever the board of supervisors shall have established any levee, or drainage district, or change of any natural watercourse and the levee, ditch, drain, or watercourse as surveyed and located crosses the right-of-way of any railroad company, the county auditor shall immediately cause to be served upon such railroad company, in the manner provided for the service of original notices, a notice in writing stating the nature of the improvement to be constructed, the place where it will cross the right-of-way of such company, and the full requirements for its complete construction across such right-of-way as shown by the plans, specifications, plat, and profile of the engineer appointed by the board, and directing such company to construct such improvement according to said plans and specifications at the place designated, across its right-of-way, and to build and construct or rebuild and reconstruct the necessary culvert or bridge where any ditch, drain, or watercourse crosses its right-of-way, so as not to obstruct, impede, or interfere with the free flow of the water therein, within thirty days from the time of the service of such notice upon it.
Iowa Code § 468.109
Referred to in §468.110, 468.112
Manner of service, R.C.P. 1.302 - 1.315