In all areas of special flood hazards the following standards are required.
(A) Anchoring.
(1) All new construction and substantial improvements shall be anchored to prevent flotation, collapse or lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy.
(2) New construction, substantial improvements, and repair to structures that have sustained substantial damage shall be constructed with materials and utility equipment that are flood-damage resistant and conform to the provisions of FEMA Technical Bulletin 2, Flood Damage-Resistant Material Requirements. This includes, but is not limited to, flooring, interior and exterior walls, wall coverings and other materials installed below the base flood elevation plus one foot.
(3) All manufactured homes to be placed, or substantially improved, shall be elevated so that the lowest floor is one foot above the base flood elevation and shall be anchored to resist flotation, collapse, or lateral movement by providing over-the-top and frame ties to ground anchors. This includes manufactured homes located outside a manufactured home park or subdivision, in a new manufactured home park or subdivision, in an existing manufactured home park or subdivision, in an expansion to an existing manufactured home park in which a manufactured home has incurred substantial damage as a result of a flood. Specific requirements shall be that:
(a) Over-the-top ties be provided at each of the four corners of the manufactured home, with two additional ties per side at intermediate locations, with mobile homes less than 50 feet long requiring one additional tie per side;
(b) Frame ties be provided at each corner of the home with five additional ties per side at intermediate points, with manufactured homes less than 50 feet long requiring four additional ties per side; and
(c) All components of the anchoring system be capable of carrying a force of 4,800 pounds.
(4) All manufactured homes, as specified in division (A)(3) above, shall be placed on a permanent foundation which itself is securely anchored and to which the structure is securely anchored so that it will resist flotation, lateral movement, and hydrostatic and hydrodynamic pressures. Anchoring may include, but not be limited to, the use of over-the-top or frame ties to ground anchors.
(B) Construction materials and methods.
(1) All new construction and substantial improvements shall be constructed with materials resistant to flood damage.
(2) All new construction and substantial improvements shall be constructed using methods and practices that minimize flood damage.
(3) Electrical, heating, ventilation, plumbing, and air conditioning equipment and other service facilities shall be designed and/or located so as to prevent water from entering or accumulating within the components during conditions of flooding.
(C) Utilities.
(1) All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of flood waters into the system;
(2) New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of flood waters into the systems and discharge from the systems into flood waters; and
(3) On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.
(4) The bottom of all electrical, heating, plumbing, ventilation and air conditioning equipment, appliances, fixtures and components, HVAC duct work and duct systems, and any other utility service equipment, facilities, machinery, or connections servicing a structure shall be elevated one foot above the base flood elevation (BFE). This includes, but is not limited to, furnaces, oil or propane tanks, air conditioners, heat pumps, hot water heaters, ventilation duct work, washer and dryer hook-ups, electrical junction boxes, and circuit breaker boxes. Systems, fixtures, equipment and components shall not be mounted on or penetrate through breakaway walls intended to fail under flood loads. Connections or other equipment that must be located below the BFE plus one foot elevation are permitted only when no other elevation alternative is available and provided they are designed and installed to prevent water from entering or accumulating within the components and to resist hydrostatic and hydrodynamic loads and stresses, including the effects of buoyancy, during the occurrence of the base flood event. Electrical wiring systems that must be located below the BFE plus one foot shall conform to the standards for wet locations.
(D) Subdivision proposals.
(1) All subdivision proposals shall be consistent with the need to minimize flood damage;
(2) All subdivision proposals shall have public utilities and facilities such as sewer, gas, electrical and water systems located and constructed to minimize flood damage;
(3) All subdivision proposals shall have adequate drainage provided to reduce exposure to flood; and
(4) Base flood elevation data shall be provided for subdivision proposals and other proposed development which contain at least 50 lots or five acres (whichever is less).
(E) Standards for streams without established base flood elevations, floodways and/or flood mapping.
(1) The Zoning Official shall obtain, review and reasonably utilize any base flood elevation and floodway data available from a federal, state or other source, including data developed pursuant to §§ 15.3.3.(b) or 15.5.1.(d)(4) of these regulations or § 6-6-1(7) of the town's subdivision regulations, as criteria for requiring that new construction, substantial improvements or other development in A, or AE Zones on the community's FIRM meet the standards in § 15.5.2.
(2) In AE Zones where base flood elevations have been determined, but before a floodway is designated, no new construction, substantial improvement, or other development (including fill) shall be permitted which will increase base flood elevations more than one foot at any point along the watercourse when all anticipated development is considered cumulatively with the proposed development.
(3) The Zoning Official may request or accept floodway data of an applicant for watercourses without FEMA-published floodways. When such data is provided by an applicant or from any other source, the town shall adopt a regulatory floodway. The floodway shall be based on only the principle that the floodway must be able to convey the waters of the base flood without increasing the water surface elevation more than one foot at any point along the watercourse.
(4) Where no base flood elevation (BFE) or floodway data is available, the Zoning Enforcement Official shall obtain, review and reasonably utilize any base flood elevation and floodway data available from a Federal, State, or other source, as criteria for requiring that new construction, substantial improvements, or other development in any area of potential, demonstrable or historical flooding within the community meet the standards in § 15.5.2. A registered professional engineer must determine the BFE in accordance with accepted hydrologic and hydraulic engineering practices and document the technical methods used. Studies, analyses and computations shall be submitted in sufficient detail to allow thorough review and approval.
(Ord. passed 6-22-1981; Ord. passed 12-19-1988; Ord. passed 5-31-2022)
Editor’s note:
TM Volume 14, page 122; TM Volume 16, page 262, Amended