(A) Paved routes.
(1) Bridges on paved routes shall be built with a minimum width of 30 feet. Wider structures will be installed when there are issues relating to Iowa DOT 30-foot six-inch wide standard bridge designs, traffic counts per the farm-to-market design aids, oversized vehicles, pedestrian facilities, biking usage or other issues where the additional width is felt to be warranted.
(2) Culverts under paved roads shall be concrete.
(3) Pipe culverts larger than 54 inches in diameter may be substituted with reinforced box culverts.
(4) Design for drainage structures will be governed by accepted hydraulic design standards. Input from IDNR, Corp of Engineers, Iowa DOT, NRCS or USGS may impact the size and type of the structure to be placed.
(5) Drainage flows and livestock will use separate structures whenever possible.
(B) Service Level A routes.
(1) Bridge width will normally be a minimum of 24 feet or to the previous width, whichever is greater. Wider structures will be installed when there are issues relating to Iowa DOT 24-foot six-inch wide standard bridge designs, traffic counts per the farm-to-market design aids, oversized vehicles, pedestrian facilities, biking usage or other issues where the additional width is felt to be warranted.
(2) Culverts may be metal or concrete. Pipe culverts larger than 54 inches in diameter may be substituted with reinforced box culverts.
(3) Design for drainage structures will be governed by accepted hydraulic design standards. Input from IDNR, Corp of Engineers, Iowa DOT, NRCS or USGS may impact the size and type of the structure to be placed.
(4) Drainage flows and livestock will use separate structures whenever possible.
(C) Service Level B and C routes. Bridge width will normally be a minimum of 24 feet or to the previous width. Wider structures will be installed when there are issues relating to Iowa DOT 24-foot six-inch wide standard bridge designs, traffic counts per the farm-to-market design aids, oversized vehicles, pedestrian facilities, biking usage or other issues where additional width is felt to be warranted. Bridges may be replaced with low water crossings at the discretion of the county’s Board of Supervisors.
(D) Entrance bridges.
(1) Any and all bridges/drainage structures that are fully or partially in the road right-of-way that serve as entrances to private property from the public roadway shall be considered the jurisdiction and responsibility of the county.
(2) If a structure does not sit fully or partially in the road right-of-way, it will be considered a private structure and not under the jurisdiction of the county.
(3) Any and all previous agreements in violation of this clause are rendered null and void.
(4) The current County Entrance Policy shall remain in effect.
(Ord. 32, passed 4-12-2016)