§ 155.31 CLASSIFICATION, SUITABILITY OF LAND.
   (A)   Classification of land for subdivision. The land within the subdivision jurisdiction of the city shall be classified into the following categories in relation to topographical conditions. The land shall be subdivided according to the regulations for that category. The U.S. Geological Survey of the area shall be used to determine slopes, unless other information can be furnished the Planning Commission showing the elevations and contours.
 
Land Type
Percentage of Slope
I
15% or less
II
16% to 25%
III
26% to 35%
IV
36% or greater
 
   (B)   Suitability of land for subdivision.
      (1)   Sinkholes.
         (a)   Sinkholes and other depressions over abandoned mines shall not be developed unless proof can be given that the sinkhole as well as the surrounding area is safe for development. This proof must be reviewed by the City Engineer for his approval, the soil conservation officer of the area for his opinion, and other agencies who have jurisdiction. The Planning Commission may increase the reserved area around the sinkhole if deemed necessary for the safety and welfare of the community.
         (b)   Natural sinkholes and other similar depressions and the area within 25 feet horizontally from the lowest point of the sinkhole, or that area subject to periodic flooding, whichever is greater, shall be preserved in its natural state for the purpose of providing drainage of the surrounding area. No building, street, or any other improvement shall be placed in this area. The Planning Commission shall have the power to increase the reserved area around the sinkhole if drainage conditions warrant this action. The sinkhole may be “punched” or otherwise altered to improve drainage.
      (2)   Flood hazards. Land subject to flooding shall not be platted for residential use or for any other use which may increase the danger to health, life, or property or aggravate erosion or flood hazards. This land within the subdivision shall be set aside on the plat for those uses as will not be endangered by periodic or occasional inundation or will not result in conditions contrary to the public welfare. To ensure that lots will be located only where they will provide flood-free house sites, the Planning Commission may require the subdivider to provide elevation and flood profiles to demonstrate that the house sites will be completely free from the danger of flooding.
      (3)   Type IV land. Where development is proposed on Type IV land, the Planning Commission shall review all construction drawings as well as the preliminary plats and final plans. This shall include construction drawings of all buildings, including foundations, and other improvements to the land.
      (4)   Premature development. The Planning Commission may refuse to approve what it considers to be scattered or premature subdivision of land which would involve danger or injury to the public health, safety, welfare, or prosperity by reason of lack of adequate water supply, schools, proper drainage, good roads and transportation facilities, or other public services, or which would necessitate an excessive expenditure of public funds for supply of these services.
      (5)   If the Planning Commission finds that land proposed to be subdivided is unsuitable for subdivision development due to poor drainage, rock formations, and other conditions that may increase the danger to health, life, or property, or aggravate erosion or flood hazards; and, if from adequate investigation, conducted by all the public agencies concerned, is determined that in the best interest of the public the land or a portion thereof should not be platted and developed for the purpose proposed, the Planning Commission shall not approve the land or portions thereof for subdivision.
(Ord. 930.1, passed 3-15-71) Penalty, see § 155.99