Subdivisions which have land within floodplains or land subject to flooding shall meet the following design standards:
(A) The following sources of floodplain information shall be used for the purposes of this chapter:
(1) The County Zoning Ordinance floodplain regulations;
(2) The Federal Insurance Administration report, entitled “The Flood Insurance Study for the County of Cass, Indiana,” dated September 3, 2014, with the accompanying flood insurance rate maps and flood boundary-floodway maps, along with subsequent revisions to the text or maps; and
(3) Detailed site studies completed for the Drainage Plan and Erosion Control Plan as required by this chapter.
(B) If a subdivision contains land in that part of the floodplain designated as a floodway, the floodway shall be preserved and not diminished in capacity by filling or obstruction, except as approved by the DNR, in writing. No residential building site may be located within the floodway.
(C) If a subdivision contains land in that part of the floodplain designated as a floodway fringe, the Plan Commission may approve such subdivision provided that:
(1) All streets are elevated sufficiently to be above the regulatory flood;
(2) All lots for residential usage have a flood protection grade two feet above the regulatory flood elevation;
(3) Where provided, water and sanitary sewer facilities are constructed to eliminate contamination of, or by, floodwater; and
(4) Approval to fill the area from DNR has been obtained in writing.
(D) Where a subdivision is proposed within an area of the floodplain for which floodway and floodway fringe designations have not been made, the Plan Commission shall not approve the subdivision unless:
(1) All streets are elevated sufficiently to be above the regulatory flood;
(2) All lots for residential usage have a flood protection grade of two feet above the regulatory flood elevation;
(3) Where provided, public water and sanitary sewer facilities are constructed to eliminate contamination of, or by, floodwater; and
(4) Filling to achieve the above will not raise the level of the regulatory flood more than one- tenth of one foot for that reach of the stream. The filling in the floodplain must be approved in writing by DNR.
(E) Areas which are not in the floodplain, but contain soils which are subject to flooding, may be approved for subdivision by the Plan Commission; provided that the subdivider fills the affected areas of the subdivision to an elevation sufficient to place building sites and streets two feet above ponding levels.
(F) In areas characterized by soils having a high seasonal water table, as determined by the County Soil and Water Conservation District, lots shall be limited to slab-type construction, unless the Plan Commission determines that appropriate engineering techniques will be applied to alleviate the subsurface problem.
(Prior Code, § 152.101) (Ord. 87, passed 4-18-1988; Ord. 2015-04, passed 4-20-2015)