1741.03  UTILIZATION OF FLOODPLAIN AREA.
   (a)   Floodway (F1).
      (1)   Within any floodway area (F1), no encroachments, including fill, new construction, substantial improvements, or other development shall be permitted unless it has been demonstrated through hydrologic and hydraulic analysis performed in accordance with standard engineering practice that the proposed encroachment will not result in any increase in the Base Flood Elevation.
      (2)   Because floodways present increased risk to human life and property due to their relatively faster and deeper flowing waters, the Floodway shall be preserved to the greatest extent possible.
      (3)   New development shall not be permitted in the floodway where reasonable alternatives exist elsewhere. In addition to the requirements below the applicant shall demonstrate that there are no reasonable alternatives other than the floodway encroachment before a permit is issued.
      (4)   When the floodway is the only reasonable alternative the applicant shall demonstrate that the floodway encroachment is the minimum necessary to accomplish the project.
      (5)   All permitted uses, activities, and development shall be undertaken in strict compliance with the flood proofing and related provisions contained herein, and in all other applicable codes, ordinances and regulations.
   (b)   Floodway Fringe (F2) and Approximated Floodplain (F4).
      (1)   In the Floodway Fringe (F2) and Approximated Floodplain (F4), any development and/or use of land shall be permitted provided that all such uses, activities and/or development shall be undertaken in strict compliance with the flood-proofing and related provisions contained herein and in all other applicable codes, ordinances and regulations.
      (2)   In the Approximated Floodplain (F4) the Floodplain Administrator shall review, or shall cause to be reviewed, all proposed development not covered below to determine the amount being invested and the specific flood risk at the building site and assign a "minimal, moderate or significant" risk level.
         A.   Development determined to represent a minimal risk and costing less than $10,000 on the enactment date of this article and thereafter adjusted for inflation shall be required to provide "Point on Boundary" elevation data and, when available, historic flood heights. The Charles Town City Engineer, hereinafter referred to as the City Engineer, shall attempt to determine a height that will be reasonably safe from flooding using this elevation data. If after review the data is found satisfactory, the Floodplain Administrator shall enter the flood height in Section "G" of the Elevation Certificate. Any new or substantially improved structures permitted using this method (other than appurtenant structures) shall be required to have the lowest floor elevated at least three (3) feet above the highest adjacent grade even if the "point on boundary" or historic flood height data would indicate a lower flood elevation. Elevating three feet above the HAG will result in more affordable flood insurance rates and added safety. If this method is not adequate to allow the City Engineer to confidently determine the flood height or if the applicant is not satisfied with the height determined by the City Engineer, the applicant shall then be required to utilize one of the alternate methods set forth in subsections b below.
         B.   Development determined to represent a low to moderate risk and/or costing less than $50,000 on the enactment date of this article and thereafter as adjusted for inflation shall either:
            1.   Provide the results from the most current version of a Quick-2 engineering analysis, or
            2.   Attempt to obtain a Base Flood Elevation by submitting a Letter of Map Amendment request to FEMA, or
            3.   Obtain flood height data by using the USGS methodology set forth in the USGS Water Resources Investigations Report 87-4111.
The semi-detailed method used will be reviewed by the City Engineer to determine a "Community Flood Elevation". The City Engineer shall enter the "Community Flood Elevation" in Section "G" of the Elevation Certificate.
         C.   Development determined to represent a high risk and/or costing more than $50,000 shall develop a Base Flood Elevation using a detailed engineering study method such as HEC-ras. This data shall be prepared and certified by a registered professional engineer, who shall certify that the methods used correctly reflect currently accepted technical concepts. The resultant study shall include a cover letter, signed by the responsible professional, providing a statement of findings in basic terms and a completed Elevation Certificate including Base Flood Elevation. In addition, studies, analyses, computations, etc. shall be submitted in sufficient detail to allow a thorough technical review by the Floodplain Administrator. If Developer submits this Detailed Study Base Flood Elevation as a map amendment significant savings on flood insurance can be realized.
      (3)   All subdivision proposals and other proposed new developments which are proposed to take place either fully or partially within the Approximated Floodplain area (F4) and which are greater than ten (10) lots or two (2) acres, whichever is the lesser, shall include base flood elevation data.
         A.   This data may be available from an authoritative source, such as the U.S. Army Corps of Engineers, U.S. Geological Survey, USDA Natural Resource Conservation Service or state and local water resource department.
         B.   If the required data is not available from other sources the applicant shall develop the technical data using detailed methodologies comparable to those contained in a FIS. This data shall be prepared and certified by a registered professional engineer, who shall certify that the methods used correctly reflect currently accepted technical concepts.
   (c)   AE Area Without Floodway (F3).  Within any AE area without floodway, no new construction or development shall be allowed unless it is demonstrated that the cumulative effect of the proposed development, when combined with all other existing and anticipated development, will not increase the elevation of the 100-year flood more than one (1) foot at any point. This requirement can be satisfied by utilization of the floodway area where determined.
   (d)   Alteration or Relocation of a Stream.
      (1)   Whenever a developer intends to alter or relocate a stream within the Floodplain Area the developer shall notify in writing, by certified mail, the City of Charles Town Floodplain Administrator, The WV State NFIP Coordinator, any adjacent communities and any adjacent property owners of all such intended activities prior to the alteration or relocation of the stream. Copies of all required notifications must be submitted to the Federal Insurance Administration. In addition prior to issuing the local permit the Floodplain Administrator shall require copies of all necessary permits from those governmental agencies from which Federal or State Law requires approval. Contact information for State and Federal permitting authorities as well as addresses for required notification of appropriate County, State and Federal government agencies are contained in the City of Charles Town Stream Alteration administrative procedures.
      (2)   The developer shall also assure the City of Charles Town in writing that the flood carrying capacity within the altered or relocated portion of the stream will be maintained. The Floodplain Administrator may require the applicant to demonstrate that the altered or relocated portion of stream will provide equal or greater conveyance than the original stream segment. If hydrologic and hydraulic analyses are required, they shall only be undertaken by professional engineers, who shall certify that the methods used correctly reflect currently accepted technical concepts. The resultant study shall include a cover letter, signed by the responsible professional, providing a statement of findings in basic terms. In addition, studies, analyses, computations, etc. shall be submitted in sufficient detail to allow a thorough technical review by the Floodplain Administrator and City Engineer.
      (3)   Alteration of a stream includes placement of culverts, bridges or other stream crossings. The Floodplain Administrator may require the use of certain "best practice" techniques in the construction of bridges, culverts or stream crossings to prevent damage, loss of stream crossings and localized flooding caused by blockage. These techniques may include, but are not limited to, wing walls, trash grates or requiring openings to be of sufficient size to pass debris and/or anticipated future increases in flood heights.
      (4)   All new and replacement bridges, culverts and other stream crossings shall adhere to the relevant anchoring requirements contained in this article.
      (5)   The applicant is required to provide the community a legal agreement detailing all scheduled inspections and maintenance to be performed on altered or relocated watercourses including culverts, bridges and other stream crossings. It shall be the responsibility of the applicant to transfer this agreement to the new owner when the land associated with the watercourse alteration is transferred. A copy of all new agreements shall be provided to the Floodplain Administrator. Failure to transfer the agreement and provide a signed copy to the Floodplain Administrator shall subject the violator to the penalty provisions set forth in Section 1741.07 (c).
      (6)   The applicant must submit any maps, computations or other material required by FEMA to revise the FIS and/or FIRM, when notified by the Floodplain Administrator, and must pay any fees or other costs assessed by FEMA for this purpose.
(Passed 9-19-16.)