[Ord. No. 731 §1, 8-15-2011]
A. The
legislature of the State of Missouri has in Chapter 89 (Section 89.020)
of the State Statutes delegated the responsibility to local government
units to adopt floodplain management regulations designed to protect
the health, safety and general welfare. Therefore, the Board of Aldermen
of the City of Rogersville ordains flood regulations as set out herein.
B. The
special flood hazard areas of the City of Rogersville, Missouri, are
subject to periodic inundation which results in loss of life, property,
health and safety hazards, disruption of commerce and governmental
services, extraordinary public expenditures for flood protection and
relief, and impairment of the tax base, all of which adversely affect
the public health, safety and general welfare.
C. General Causes Of The Flood Losses. These flood losses are
caused by the cumulative effect of development in any delineated floodplain
causing increases in flood heights and velocities; and by the occupancy
in flood hazard areas by uses vulnerable to floods, hazardous to others,
inadequately elevated, or otherwise unprotected from flood damages.
D. Methods Used To Analyze Flood Hazards. The Flood Insurance
Study (FIS) that is the basis of this Chapter uses a standard engineering
method of analyzing flood hazards which consist of a series of interrelated
steps.
1. Selection of a base flood that is based upon engineering calculations
which permit a consideration of such flood factors as its expected
frequency of occurrence, the area inundated, and the depth of inundation.
The base flood selected for this Chapter is representative of large
floods which are characteristic of what can be expected to occur on
the particular streams subject to this Chapter. It is in the general
order of a flood which could be expected to have a one percent (1%)
chance of occurrence in any one (1) year as delineated ion the Federal
Insurance Administrator's FIS, and illustrative materials dated September
17, 2010, as amended, and any future revisions thereto.
2. Calculation of water surface profiles are based on a standard hydraulic
engineering analysis of the capacity of the stream channel and overbank
areas to convey the regulatory flood.
3. Computation of a floodway required to convey this flood without increasing
flood heights more than one (1) foot at any point.
4. Delineation of floodway encroachment lines within which no development
is permitted that would cause any increase in flood height.
5. Delineation of floodway fringe, i.e., that area outside the floodway
encroachment lines, but still subject to inundation by the base flood.