R 323.1315 Criteria for determining permissibility of encroachments.

Rule 315. (1) An encroachment in the floodway which, acting alone or in combination with existing or future similar works, may cause harmful interference shall not be approved. In making this determination, an analysis shall be made for a range of discharges up to and including the 100-year flood discharge modified to reflect changes in land use and development reasonably anticipated to occur within the watershed up to twenty years from the date of application. (2) A bridge or culvert, constructed or reconstructed, shall be capable of passing the 100- year flood without causing harmful interference. (3) An encroachment in the floodplain, landward of the floodway limits, which, acting alone or in combination with existing or future similar works, does not cause harmful interference may be permitted.