Flood-prone area regulations applicable to all districts.
A. Alluvial soils regulations.
(1) Alluvial soil floodplain areas.
(a) "Alluvial soils" are those areas shown on the official Chester County Soil Survey as including soils identified as alluvial soils on the Official Zoning Map. The alluvial soils areas contain one or more of the soil types which are identified by the Soil Survey for Chester County as alluvial or "soils of floodplains that are subject to overflow" or a closely similar term.
(b) The alluvial soils areas shall be regulated by Subsection A. Where an appropriate accurate detailed study of the extent of the one-hundred-year floodplain is available, the alluvial soils areas regulations shall not apply.
(2) Approval procedure. Where an applicant proposes any grading or construction of a building or installation of a septic system within alluvial soils areas or areas within 50 feet of alluvial soils areas as shown on the Chester County Soil Survey and an accurate detailed official floodplain study acceptable to the Zoning Officer does not exist along that segment, then such areas shall be considered as part of the one-hundred-year floodplain and regulated as such, unless the applicant provides and funds a detailed on-site survey to determine the exact extent of areas susceptible to a one-hundred-year flood and the applicant then proves that any alteration or development would meet the one-hundred-year floodplain regulations within the areas determined to be within the one-hundred-year floodplain.
(a) Such on-site survey shall be made by a professional engineer or registered landscape architect who has demonstrated experience in the hydrologic field and shall be completed in accordance with accepted on-site survey techniques. The Zoning Officer may require that such study distinguish the one-hundred-year floodway from the one-hundred-year flood-fringe if necessary to determine compliance with this chapter. [Amended 3-18-2003 by Ord. No. 129-D-03]
(b) The applicant shall fund reasonable costs to have such study reviewed by the Township Engineer. The Zoning Officer shall then accept or not accept such study based upon such professional review.
B. Floodplain regulations.
(1) Intent of floodplain provisions. The intent of the provisions is to:
(a) Promote the general health, welfare and safety of the township.
(b) Encourage the utilization of appropriate construction practices in order to prevent or minimize flood damage in the future.
(c) Minimize danger to public health and safety by protecting water supply, sanitary sewage disposal and natural drainage.
(d) Reduce financial burdens imposed on the community, its governmental units and its residents by preventing the unwise design and construction of development in areas subject to flooding.
(e) Regulate development of floodplains in accordance with the Federal Insurance Administration's Requirements for Flood Management and the Pennsylvania Floodplain Management Act.
(2) Applicability. Provisions of all other codes, ordinances and regulations shall be applicable insofar as they are consistent with the provisions of this chapter and the township's need to minimize the hazards and damage resulting from flooding.
(3) Establishment of the floodplain.
(a) The floodplain designated on the Official Zoning Map includes all areas subject to inundation by the waters of the one-hundred-year flood. The source of this delineation shall be the Flood Insurance Study for the Township of East Goshen, Chester County, Pennsylvania, as prepared by the Federal Emergency Management Agency (FEMA) . The floodplain shall be comprised of the three subareas as follows:
[1] Floodway (F1) . That portion of the floodplain required to carry and discharge the waters of the one-hundred-year flood without increasing the water surface elevation at any point more than 1.0 foot above existing conditions, as demonstrated in the Flood Insurance Study referenced above.
[2] Floodway-Fringe (F2) . Those portions of land within the floodplain subject to inundation by the one-hundred-year flood, lying beyond the floodway in areas where detailed study data and profiles are made available by the Flood Insurance Study referenced above.
[3] Approximated Floodplain (F3) . Those portions of land within the floodplain subject to inundation by the one-hundred-year flood, where a detailed study has not been performed, but where a one-hundred-year floodplain boundary has been approximated by the Flood Insurance Study referenced above. The term shall also include floodway areas which have been identified in other available studies or sources of information, as approved by the Township Engineer, for those floodplain areas where no floodway has been identified in the Flood Insurance Study.
(b) The delineation of the floodplain may be revised, amended and modified by the Board of Supervisors in compliance with the National Insurance Program when:
[1] There are changes through natural or other causes.
[2] Changes are indicated by future detailed hydrologic and hydraulic studies. All such changes shall be subject to the review and approval of the Federal Insurance Administrator, or his/her successor.
(4) Boundary dispute. Should a dispute concerning any floodplain boundary arise, an initial determination shall be made by the Zoning Officer. Any party aggrieved by this decision may appeal to the Zoning Hearing Board under the provisions of Article VIII. The burden of proof shall be on the appellant.
(5) Uses permitted. Only the following uses, exclusive of buildings, are permitted in a floodplain, provided that if located in the floodway area of the floodplain, there shall be no increase in the one-hundred-year flood elevation:
(a) Customary agricultural operations, exclusive of buildings as defined in this chapter.
(b) Parks, playgrounds and recreational uses.
(c) Forestry and wood production, excluding storage and mill structures.
(d) Outdoor plant nurseries.
(6) Uses prohibited. The following shall not be placed or caused to be placed in a floodplain:
(a) All new, or the enlargement and expansion of, improved residential dwellings and all commercial, institutional or industrial structures, including hospitals, nursing homes, jails and mobile homes and their accessory structures, including parking areas.
(b) Any new or substantially improved structure which will be used for the production or storage of any of the following materials or substances, or which will be used for any activity requiring the maintenance of a supply (more than 550 gallons or other comparable volume or any amount of radioactive substances) of any of the following materials or substances on the premises: acetone, ammonia, benzene, calcium carbide, carbon disulfide, celluloid, chlorine, hydrochloric acid, hydrocyanic acid, magnesium, nitric acid and oxides of nitrogen, petroleum products (gasoline, fuel oil, etc. ) , phosphorus, potassium, sodium, sulfur and sulfur products, pesticides (including insecticides, fungicides and rodenticides) and radioactive substances, insofar as such substances are not otherwise regulated.
(c) The filling of marshlands, dredging, removal of topsoil or damming or relocation of any watercourse except with the approval of the Pennsylvania Department of Environmental Protection.
(d) Sanitary landfill, dump, junkyard, outdoor storage or disposal of vehicles and/or materials, including manure and hazardous substances listed in Subsection B(6) (b) .
(e) On-site disposal systems.
(f) Fences, except two-wire fences.
(g) Other matter which may impede, retard or change the direction of the flow of water that will catch or collect debris carried by such water, or that is placed where the natural flow of the stream or flood waters would carry the same downstream to the damage or detriment of either public or private property adjacent to the floodplain.
(7) Nonconforming uses and structures in the floodplain. Nonconforming buildings, structures and uses of land within the floodplain shall be regulated under the provisions of Article VI of this chapter, but the following additional regulation shall also apply.
(a) Existing nonconforming uses or structures located in the floodway shall not be expanded or enlarged.
(b) The modification, alteration, repair, reconstruction or improvement of any kind to a nonconforming use or structure in a floodway, and the modification, expansion, enlargement, alteration, repair, reconstruction or improvement of any kind to a nonconforming use or structure located in a floodway-fringe or approximated floodplain must be authorized as a special exception by the Zoning Hearing Board under the provisions of Article IX of this chapter. In considering such special exceptions, the Zoning Hearing Board shall apply the following standards and criteria:
[1] Assure itself that the proposed change is consistent with the spirit, purpose and intent of this chapter.
[2] Assure itself that the proposed use is feasible and suitable in relation to the land use capabilities of the property in question, particularly its capabilities in terms of a suitable water supply, drainage, sewage disposal, topography, soil conditions and ecological considerations.
[3] Determine that the proposed change will serve the best interests of the township, the convenience of the community, where applicable, and the public welfare.
[4] Ascertain the adequacy of sanitation and public safety provisions, where applicable, and require a certificate of adequacy or permit for sewage and water facilities from the Chester County Health Department or the appropriate governmental agency in any case required herein or deemed advisable.
[5] If any filling or alteration to the elevation of the ground in the Floodway, Floodway-Fringe or Approximated Floodplain, or any alteration or relocation of any perennial stream is contemplated, the Zoning Hearing Board shall determine that the developer has notified, in writing, by certified mail, all adjacent communities which may be affected by such alterations and has submitted copies of such notification to the township and to the Federal Insurance Administrator and, in addition, has obtained a permit from the Pennsylvania Department of Environmental Protection, Division of Dams and Encroachments.
[6] Any modification, alteration, repair, reconstruction or improvement of any kind to a nonconforming structure located in the floodway shall be elevated and/or floodproofed to the greatest extent possible.
[7] Any modification, alteration, repair, reconstruction, expansion or improvement of any kind to a nonconforming use or structure regardless of location within the floodplain to an extent or amount of 50% or more of its market value shall be undertaken only in full compliance with the provisions of this and any other applicable township ordinances.
[8] All buildings and structures shall be constructed and placed on the lot so as to offer the minimum obstruction to the flow of water and shall be designed to have a minimum obstruction effect upon the flow and height of floodwater.
[9] The Zoning Hearing Board shall receive assurances that no materials that are buoyant, flammable, explosive or, in times of flooding, could be injurious to human, animal or plant life shall be stored below base flood elevation.
[10] The Zoning Hearing Board shall require that new construction and substantial improvements be anchored to prevent flotation and lateral movement and be constructed with flood-resistant material and methods in accordance with the floodproofing standards of Subsection B(10) .
[11] The Zoning Hearing Board shall also apply the criteria set forth in the Rules and Regulations of the Federal Emergency Management Agency (FEMA) , Title 24, Chapter X, Subchapter B, Part 60, Section 60. 6(a) (Federal Register, Volume 41, No. 207, October 26, 1976) , as may be amended from time to time, in the granting of special exceptions. Said rules and regulations are as follows:
[a] Special exceptions shall not be issued by a community within any designated regulatory floodway if any increase in flood levels during the base flood discharge would result.
[b] Special exceptions may be issued by the Zoning Hearing Board for new construction and substantial improvements to be erected on a lot of 1/2 acre or less in size contiguous to and surrounded by lots with existing structures constructed below the base flood level, in conformance with the procedures of Subsections B(3) , (4) and (5) .
[c] Special exceptions shall only be issued by the Zoning Hearing Board upon:
[i] A showing of good and sufficient cause.
[ii] A determination that failure to grant the special exception would result in exceptional hardship to the applicant.
[iii] A determination that the granting of a special exception will not result in increased flood heights, additional threats to public safety, extraordinary public expense, create nuisances, cause fraud on or victimization of the public or conflict with existing local laws or ordinances.
[d] Special exceptions shall only be issued upon a determination that the special exception is the minimum necessary, considering the flood hazard, to afford relief.
[e] The Zoning Hearing Board shall notify the applicant, in writing, over the signature of a community official, that the issuance of a special exception to construct a structure below the base flood level will result in increased premium rates for flood insurance up to amounts as high as $25 for $100 of insurance coverage, and such construction below the base flood level increases risks to life and property. Such notification shall be maintained with a record of all special exception actions as required in Subsection B(7) (b) [11][f].
[f] The Zoning Hearing Board shall maintain a record of all special exception actions, including justification for their issuance, and report such special exceptions issued in its annual report submitted to the Board of Supervisors.
(8) Modifications to the floodplain or stream courses for access. Where no other access is available, modifications to the elevation of the ground in the Floodway, Floodway-Fringe or Approximated Floodplain, or any alteration or relocation of any perennial stream, may be permitted when approval is obtained from the Pennsylvania Department of Environmental Protection and the township in accordance with the following township regulations:
(a) A plan shall be prepared and presented to the Board of Supervisors (or Zoning Hearing Board in the case of special exception procedures relating to nonconforming uses) which shows or is accompanied by:
[1] The name and address of applicant.
[2] The name and address of owner of land on which proposed construction is to occur.
[3] Site location.
[4] Name of engineer, surveyor or other qualified person responsible for providing the information.
[5] A plan of the site, including plans of subdivisions or land developments lying partially in the floodplain showing the exact size and location of the proposed construction as well as any existing buildings or structures. This plan will show the location of the proposed work with respect to the floodplain areas, proposed lots and sites, cuts, fills, flood or erosion protective facilities, areas subject to special deed restrictions and detailed information giving the location and elevation of proposed streets, bridges, pipes, stream alterations or relocations, public utilities and building sites. All such plans shall also show contours at intervals required by Chapter 205, Subdivision and Land Development, and identify accurately the boundaries of the floodplain. In addition, it is required that all subdivision proposals greater than 50 lots or five acres, whichever is the lesser, and which incorporate areas of the floodplain shall include base flood elevation data.
(b) The developer shall submit a copy of a notification prepared, in writing, by certified mail, to the Federal Insurance Administrator and to adjacent communities which may be affected by modifications to the elevation of ground in a floodplain or alterations or relocations of streams.
(c) The developer shall submit a copy of a permit from the Pennsylvania Department of Environmental Protection for the modifications to the grade or alterations or relocations to the stream, or evidence from such agency that such permit is not required.
(d) Fill.
[1] Proposed fills shall meet the following minimum standards:
[a] Fill shall consist of soil or rock materials only. Sanitary landfills shall not be permitted.
[b] Fill material shall be compacted to provide the necessary stability and resistance to erosion, scouring or settling.
[c] Fill slopes shall be no steeper than one vertical on three horizontal, unless substantiating data justifying steeper slopes are submitted to and approved by the Zoning Officer.
[d] Fill shall be used only to the extent to which it does not adversely affect adjacent properties.
[2] Plans submitted under the provisions of this subsection shall be subject to the review and approval of the Board of Supervisors according to procedures set forth in Chapter 205, Subdivision and Land Development.
(9) Installation of utility facilities in the floodplain. Where utility lines or on-site facilities are required to be installed or replaced, the following minimum standards shall apply:
(a) All new or replacement water systems, located in the floodplain, whether public or private, shall be floodproofed to the base flood elevations.
(b) All new or replacement sanitary disposal systems located within the floodplain, whether public or private, shall be floodproofed to the base flood elevation.
(c) All other new or replacement, public and/or private, utilities and facilities shall be elevated or floodproofed to the base flood elevation.
(10) Minimum floodproofing standards. Where a special exception has been requested under the provisions of Subsection B(7) of this section in which it is anticipated that a building or use will be modified, altered, repaired, reconstructed, expanded or improved in any way, the following minimum standards shall apply to floodproofing:
(a) All substantial improvements of residential structures must have the lowest floor (including basement) elevated to the base flood elevation. All substantial improvements of nonresidential structures must have the lowest floor (including basement) elevated to the base flood elevation or, together with attendant utility and sanitary facilities, be designed so that below the base flood elevation, the structure is watertight with walls substantially impermeable to the passage of water and with structural components having the capability of resisting hydrostatic and hydrodynamic loads and effects of buoyancy.
(b) If fill is used to raise the finished surface of the lowest floor to the base flood elevation, such fill shall extend beyond a structure for a sufficient distance to provide acceptable access. For residential structures, fill shall extend laterally 15 feet beyond the building line from all points. For nonresidential structures, fill shall be placed to provide access acceptable for intended use. At-grade access, with fill extending laterally 15 feet beyond the building line, shall be provided to a minimum of 25% of the perimeter of a nonresidential structure.
(c) Mobile homes shall be placed on a permanent foundation and shall be elevated on compacted fill or on pilings so that the lowest floor of each mobile home shall be at the base flood elevation.
(d) Where there are existing mobile homes, adequate surface drainage and access for a mobile home hauler shall be provided.
(e) When mobile homes are to be elevated on pilings, lots shall be large enough to permit steps. Piles shall be placed in stable soil no more than 10 feet apart and reinforcement shall be provided for pilings more than six feet above the ground level.
(f) All buildings and structures shall be firmly anchored in accordance with accepted engineering practices to prevent flotation, collapse and lateral movement, thus reducing the threat to life and property and decreasing the possibility of the blockage of bridge openings and other restricted sections of the watercourse.
(g) All air ducts, large pipes and storage tanks located at or below the base flood elevation shall be firmly anchored to resist flotation.
(h) All existing mobile homes shall be anchored to resist flotation, collapse or lateral movement by providing over-the-top and frame ties to ground anchors. Specifically:
[1] Over-the-top ties shall be provided at each of the four corners of the mobile home, with two additional ties per side at intermediate locations. Mobile homes less than 50 feet long require only one additional tie per side.
[2] Frame ties shall be provided at each corner of the home with five additional ties per side at intermediate points. Manufactured/mobile homes less than 50 feet long require four additional ties per side.
[3] All components of the anchoring system shall be capable of carrying a force of 4,800 pounds.
[4] Any additions to a mobile home shall be similarly anchored.
(i) Where floodproofing is utilized for a particular structure in accordance with this chapter, a registered professional engineer or architect shall certify, at the owner's expense, that the floodproofing methods are adequate to withstand the flood depths, pressures, velocities, impact and uplift forces and other factors associated with the base flood, and a record of such certificates indicating the specific elevation (in relation to mean sea level) to which such structures are floodproofed shall be maintained by the Zoning Officer.
(j) Space below the lowest floor.
[1] Fully enclosed space below the lowest floor (including basement) is prohibited.
[2] Partially enclosed space below the lowest floor (including basement) which will be used solely for the parking of a vehicle, building access or incidental storage in an area other than a basement shall be designed and constructed to allow for the automatic entry and exit of floodwaters for the purpose of equalizing hydrostatic forces on exterior walls. The term "partially enclosed space" also includes "crawl spaces. " Designs for meeting this requirement must either be certified by a registered professional engineer or architect, or meet or exceed the following minimum criteria:
[a] A minimum of two openings having a net total area of not less than one square inch for every square foot of enclosed space.
[b] The bottom of all openings shall be no higher than one foot above grade.
[c] Openings may be equipped with screens, louvers, etc. , or other coverings or devices, provided that they permit the automatic entry and exit of floodwaters.
(11) Permits. The provisions of § 240-47 regarding the requirement for an issuance of zoning, occupancy and any other permits and the payment of fees shall in all respects apply to the substantial improvement of any structure within the floodplain. The permit application for said improvement shall indicate thereon the lowest floor elevation of such structure.
**Webmasters Note: The previous section has been amended as per Ordinance No. 129-D-03.
