A. Below Flood Protection Elevation: In addition to the damage prevention requirements of Section 9-1-7, all buildings to be located in the special flood hazard area shall be protected from flood damage below the flood protection elevation. These building protection requirements apply to the following situations:
1. Construction or placement of new buildings valued at more than one thousand dollars ($1,000.00).
2. Improvements made to an existing building that increases the first floor area by more than twenty percent (20%) or the market value of the building by more than fifty percent (50%). (See subsection 9-1-7B2 of this Chapter.)
3. Reconstruction or repairs made to a damaged building that are valued at or more than fifty percent (50%) of the value of the building before damage occurred.
B. Protection Methods: This building protection requirement may be met by any one of the following methods:
1. Permanent Landfills: Permanent landfills may be permitted as means of providing safe construction sites, provided:
a. The landfill, except in exceptional circumstances, be contiguous with the boundary of the regulatory flood plain and shaped, in plan, so as not to create adverse velocities or current patterns.
b. The surface of the landfill is at or above the regulatory flood protection elevation.
c. The channelward face of the fill shall be protected against erosion. If protected by vegetative cover, slopes shall be no steeper than three horizontal to one vertical (3:1). Steeper slopes shall be protected by riprap. A vertical bulkhead may be used if adequately founded and protected against scour.
d. Fill shall be of such material and so compacted to provide adequate support under saturated conditions and shall be otherwise suitable for the use intended.
e. The lowest floor (including basement) shall be at or above the FPE. The fill should extend at least ten feet (10') beyond the foundations of the building before sloping below the FPE.
f. Adequate provision is made for conducting drainage across the fill.
g. The Zoning Administrator shall maintain a record of the as- built elevation of the lowest floor of the building.
2. Elevated Structures: Structures may be permitted provided:
a. The superstructure and its major access shall be raised above the regulatory flood protection elevation by elevating members.
b. The structure and its intended use will not be damaged by the regulatory flood.
c. The elevating members are designed to withstand saturated conditions, hydrostatic pressure and to minimize scouring.
d. The size, shape, spacing and alignment of elevating members are selected to minimize turbulence and deflection of current patterns.
e. Any supporting walls have permanent openings no more than one foot (1') above grade to facilitate easy passage of ice and debris.
f. Superstructures and major access shall have low steel or low concrete at or above the regulatory flood protection elevation.
g. All areas below the FPE shall be constructed of materials resistant to flood damage. The lowest floor (including basement) and all electrical, heating, ventilating, plumbing and air- conditioning equipment and utility meters shall be located at or above the FPE. Water and sewer pipes, electrical and telephone lines, submersible pumps and other waterproofed service facilities may be located below the FPE.
h. The Zoning Administrator shall maintain a record of the as- built elevation of the lowest floor.
3. Structural Floodproofing: Structural floodproofing will be permitted only in special circumstances where other techniques for flood protection are impossible or impractical. Floodproofing measures shall be designed consistent with the regulatory flood protection, elevation for the particular area, flood velocities, durations, rate of rise, hydrostatic and hydrodynamic forces and other factors associated with floodwater. The petitioner shall submit a plan or document certified by a registered professional engineer that the floodproofing measures are consistent with the regulatory flood protection elevation and associated flood factors for the particular area. The following floodproofing measures may be required (without limitation because of specific enumeration):
a. Anchorage to resist flotation and lateral movement.
b. Installation of watertight doors, bulkheads and shutters or similar methods of construction.
c. Reinforcement of walls to resist water pressures.
d. Use of paints, membranes or mortars to reduce seepage of water through walls.
e. Addition of mass or weight to structures to resist flotation.
f. Installation of pumps to lower water levels in structures.
g. Construction of water supply and waste treatment systems so as to prevent the entrance of floodwaters.
h. Pumping facilities or comparable practices for subsurface drainage systems for buildings to relieve external foundation wall and basement flood pressures.
i. Construction to resist rupture or collapse caused by water pressure or floating debris.
j. Installation of valves or controls on sanitary and storm drains which will permit the drains to be closed to prevent backup of sewage and storm waters into the buildings or structures. Gravity draining of basements may be eliminated by mechanical devices.
k. Location of all electrical equipment, circuits and installed electrical appliances in a manner which will assure they are not subject to flooding and to provide protection from inundation by floodwater flows.
4. Nonresidential Building: A nonresidential building may be floodproofed in accordance with the following:
a. A registered professional engineer shall certify that the building has been designed so that below flood protection elevation the structure and attendant utility facilities are watertight and capable of resisting the effects of the base flood. The building design shall take into account flood velocities, duration, rate of rise, hydrostatic and hydrodynamic forces, the effects of buoyancy and impacts from debris or ice.
b. Floodproofing measures shall be operable without human intervention and without an outside source of electricity.
c. The engineer's certification and a record of the as-built elevation to which the building was floodproofed shall be maintained on file by the Zoning Administrator. (Ord. 257, 7-11-1988)