The Building Commission does not permit development in the Special Flood Hazard Areas and known flood-prone areas that create a damaging or potentially damaging increase in flood heights or velocity or threat to public health or safety.

• Within the floodway identified on the Flood Boundary and Floodway Map, or the Flood Insurance Rate Map, or engineering analysis, the following standards shall apply:
  • No development is  allowed which, acting alone or in combination with existing or future similar works, will increase the regulatory flood more than 0.14 of one foot.
  • All projects involving channel modifications or fill (including levees) the permittee is required to submit a request with the approval of the Building Commission to the Federal Emergency Management Agency to revise the regulatory flood data.
• Within all SFHAs identified as A Zones (no 100-year flood elevation and/or floodway/fringe delineation has been provided) and with a drainage area upstream of the site greater than or equal to one square mile, the following standard shall apply:
  • The total cumulative effect of the proposed development, when combined with all other existing and anticipated development, will not increase the regulatory flood elevation more than 0.14 of one foot and will not increase flood damages or potential flood damages.
• Within all SFHAs identified as A Zones (no floodway/fringe delineation has been provided) and with a drainage area upstream of the site less than one square mile, the following standard shall apply:
  • The total cumulative effect of the proposed development, when combined with all other existing and anticipated development, will not increase the regulatory flood elevation more than 0.14 of one foot and will not increase flood damages or potential flood damages.

Public Health Standards in all Special Flood Hazard Areas

No development in the SFHAs shall include locating or storing chemicals, explosives, buoyant materials, flammable liquids, pollutants, or other hazardous or toxic materials below the flood protection grade, unless such materials are stored in a floodproofed storage tank or building constructed according to local requirements.

New and replacement sanitary sewer lines and on-site waste disposal systems may be permitted providing all manholes or other aboveground openings are located above, or those which are below the base flood elevation (BFE) plus one-tenth foot are watertight, but in no case shall industrial pretreatment sampling manholes be below the base flood elevation (BFE) plus one-tenth foot.

Critical Facilities

Construction of new critical facilities shall be, to the extent possible, located outside the limits of the SFHA. Construction of new critical facilities shall be permissible within the SFHA if no feasible alternative site is available.

• Critical facilities constructed within the SFHA shall have the lowest floor elevated to or above the FPG at the site. Floodproofing and sealing measures must be taken to ensure that toxic substances will not be displaced by or released into floodwaters.
• Access routes elevated to or above the FPG shall be provided to all critical facilities to the extent possible.

Repetitive Loss Structures

In order for buildings to qualify for a claim payment under ICC coverage as a “repetitive loss structure,” the National Reform Act of 1994 requires that the building be covered by a contract for flood insurance and incur flood-related damages on two occasions during a 10-year period ending on the date of the event for which the second claim is made, in which the cost of repairing the flood damage, on the average, equaled or exceeded 25 percent of the market value of the building at the time of each such flood event.