The identified floodplain area shall be any areas of Borough of Lansdowne, classified as special flood hazard areas (SFHAs) in the Flood Insurance Study (FIS) and the accompanying Flood Insurance Rate Maps (FIRMs) dated November 18, 2009, 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 Borough of Lansdowne and declared to be a part of this chapter.
Note: Some of the following subsections may not be needed. In some instances, Zones A, AO, or AH may not appear on the FIRM, in which case the relevant subsections should be omitted. Check the FIRM carefully to see if any of these zones have been delineated.
The identified floodplain area shall consist of the following specific areas:
The Floodway Area/District identified as floodway in the FIS which represents the channel of a watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively 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.
Within any floodway area, 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 would not result in any increase in flood levels within the community during the occurrence of the base flood discharge.
No new construction or development shall be allowed, unless a permit is obtained from the Department of Environmental Protection Regional Office and is consistent with the Borough's Act 167 Stormwater Management Ordinance.
The AE Area/District without floodway shall be those areas identified as an AE Zone on the FIRM included in the FIS prepared by FEMA and for which base flood elevations have been provided in the FIS but no floodway has been delineated.
No permit shall be granted for any construction, development, use, or activity within any AE Area/District without floodway unless it is demonstrated that the cumulative effect of the proposed development would not, together with all other existing and anticipated development, increase the base flood elevation at any point.
No new construction or development shall be located within the area measured 50 feet landward from the top-of-bank of any watercourse unless a permit is obtained from the Department of Environmental Protection Regional Office and is consistent with the Borough's Act 167 Stormwater Management Ordinance.
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 one-percent-annual-chance 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 or others of demonstrated qualifications, 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.
The Shallow Flooding Area/District shall be those areas identified as Zones AO and AH on the FIRM and in the FIS. These areas are subject to inundation by one-percent-annual-chance shallow flooding where average depths are between one foot and three feet. In Zones AO and AH, drainage paths shall be established to guide floodwaters around and away from structures on slopes.
Note: Risk Map nonregulatory products, including but not limited to Coastal A Zones, non-encroaching zones, advisory flood heights, soils and shaded Zone X where floodplain is less than one square mile drainage area or less than 200 feet wide, will necessitate inclusion of this language if communities want to regulate using this data.
The identified floodplain area may be revised or modified by the Borough Council 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.
Should a dispute concerning any identified floodplain boundary arise, an initial determination shall be made by the Borough of Lansdowne Planning Commission, and any party aggrieved by this decision or determination may appeal to the Borough Council. 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.