455B.276  Floodplains — encroachment limits.
  The commission may establish and enforce rules for the orderly development and wise use of the floodplains of any river or stream within the state and alter, change, or revoke the rules. The commission shall determine the characteristics of floods which reasonably may be expected to occur and may establish by order encroachment limits, protection methods, and minimum protection levels appropriate to the flooding characteristics of the stream and to reasonable use of the floodplains. The order shall fix the length of floodplains to be regulated at any practical distance, the width of the zone between the encroachment limits so as to include portions of the flood plains adjoining the channel, which with the channel, are required to carry and discharge the flood waters or flood flow of the river or stream, and the design discharge and water surface elevations for which protection shall be provided for projects outside the encroachment limits but within the limits of inundation. Plans for the protection of projects proposed for areas subject to inundation shall be reviewed as plans for flood control works within the purview of section 455B.277. An order establishing encroachment limits shall not be issued until notice of the proposed order is given and opportunity for public hearing given for the presentation of protests against the order. In establishing the limits, the commission shall avoid to the greatest possible degree the evacuation of persons residing in the area of a floodway, the removal of residential structures occupied by the persons in the area of a floodway, and the removal of structures erected or made prior to July 4, 1965, which are located on the flood plains of a river or stream but not within the area of a floodway.
  The commission shall cooperate with and assist local units of government in the establishment of encroachment limits, floodplain regulations, and zoning ordinances relating to floodplain areas within their jurisdiction. Encroachment limits, floodplain regulations, or floodplain zoning ordinances proposed by local units of government shall be submitted to the department for review and approval prior to adoption by the local units of government. Changes or variations from an approved regulation or ordinance as it relates to floodplain use are subject to approval by the commission prior to adoption. Individual applications, plans, and specifications and individual approval orders shall not be required for works on the floodplains constructed in conformity with encroachment limits, floodplain regulations, or zoning ordinances adopted by the local units of government and approved by the commission.
[C50, 54, §455A.21; C58, 62, 66, 71, 73, 75, 77, 79, 81, §455A.35; 
82 Acts, ch 1199, §30, 96
]
C83, §455B.276
83 Acts, ch 137, §19