The identified floodplain area shall be:
Any areas of Upper Uwchlan Township classified as special flood hazard areas (SFHAs) in the Flood Insurance Study (FIS) and the accompanying Flood Insurance Rate Maps (FIRMs) dated September 29, 2017, and issued by the Federal Emergency Management Agency (FEMA), or the most-recent revision thereof, including all digital data developed as part of the Flood Insurance Study.
The above-referenced FIS and FIRMs, and any subsequent revisions and amendments, are hereby adopted by Upper Uwchlan Township and declared to be a part of this chapter.
The identified floodplain area shall consist of the following specific areas:
The Floodway Area shall be those areas identified in the FIS and the FIRM as floodway and which represent the channel of a watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without increasing the water surface elevation by more than one foot at any point. This term shall also include floodway areas which have been identified in other available studies or sources of information for those special flood hazard areas where no floodway has been identified in the FIS and FIRM.
Within any Floodway Area, no encroachments, including fill, new construction, substantial improvements, or other development permitted per any current Township ordinance, shall be permitted unless it has been demonstrated through hydrologic and hydraulic analysis performed in accordance with standard engineering practice that the proposed encroachment would not result in any increase in flood levels within the community during the occurrence of the base flood discharge.
Within any Floodway Area, no new construction or development otherwise permitted per any current Township ordinance shall be allowed, unless the appropriate permit is obtained from the Department of Environmental Protection's regional office.
The AE Area/District shall be those areas identified as an AE Zone on the FIRM included in the FIS prepared by FEMA for which base flood elevations have been provided.
The AE Area adjacent to the floodway shall be those areas identified as an AE Zone on the FIRM included in the FIS prepared by FEMA for which base flood elevations have been provided and a floodway has been delineated.
The AE Area without floodway shall be those areas identified as an AE Zone on the FIRM included in the FIS prepared by FEMA for which base flood elevations have been provided but no floodway has been determined.
No permit shall be granted within any AE Zone without floodway and 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 development, together with all other existing and anticipated development, would not result in an increase in flood levels within the entire community during the occurrence of the base flood discharge.
The A Area/District shall be those areas identified as an A Zone on the FIRM included in the FIS prepared by FEMA and for which no base flood elevations have been provided. For these areas, elevation and floodway information from other federal, state, or other acceptable sources shall be used when available. Where other acceptable information is not available, the base flood elevation shall be determined by using the elevation of a point on the boundary of the identified floodplain area which is nearest the construction site. In lieu of the above, the municipality may require the applicant to determine the elevation with hydrologic and hydraulic engineering techniques. Hydrologic and hydraulic analyses shall be undertaken only by professional engineers, who shall certify that the technical methods used correctly reflect currently accepted technical concepts. Studies, analyses, computations, etc., shall be submitted in sufficient detail to allow a thorough technical review by the municipality. In the absence of any of the above data or documentation, the community may require the elevation of the lowest floor to be at least three feet above the highest adjacent grade.
No new construction or development shall be located within the area measured 50 feet landward from the top-of-bank of any watercourse, except as permitted by the Zoning Ordinance or herein, and after obtaining any required permit from the Department of Environmental Protection's regional office.
The identified floodplain area may be revised or modified by the Board of Supervisors where studies or information provided by a qualified agency or person documents the need for such revision. However, prior to any such change to the special flood hazard area, approval must be obtained from FEMA. Additionally, as soon as practicable, but not later than six months after the date such information becomes available, a community shall notify FEMA of the changes to the special flood hazard area by submitting technical or scientific data. See § 82-22B for situations where FEMA notification is required.
Should a dispute concerning any identified floodplain boundary arise, an initial determination shall be made by the floodplain administrator, and any party aggrieved by this decision or determination may appeal to the Board of Supervisors. The burden of proof shall be on the appellant.
Prior to development occurring in areas where annexation or other corporate boundary changes are proposed or have occurred, the community shall review flood hazard data affecting the lands subject to boundary changes. The community shall adopt and enforce floodplain regulations in areas subject to annexation or corporate boundary changes which meet or exceed those in 44 CFR 60.3.