N.Y. Comp. Codes R. & Regs. tit. 6 § 502.4

Current through Register Vol. 46, No. 50, December 11, 2024

Section 502.4 - Floodplain management criteria for state projects in flood hazard areas

(a) When the administrator has not provided data for a city, town or village to designate a regulatory floodway, or if that data has been provided and such regulatory floodway has not yet been designated, or when the administrator has not identified coastal high hazard areas in a city, town or village, any State agency proposing to commence any project within a flood hazard area in that city, town or village shall do so only if it determines such project is in compliance with the following criteria:

(1) State agencies shall consider other alternative sites on which the project could be located which would not involve a flood hazard area.

(2) All necessary permits shall be acquired from those governmental agencies from which approval is required by Federal or State law, including section 404 of the Federal Water Pollution Control Act Amendments of 1972 ( 33 U.S.C. 1334).

(3) The proposed project shall:

(i) be designed (or modified) and adequately anchored to prevent flotation, collapse or lateral movement of the project;

(ii) be constructed with materials and utility equipment resistant to flood damage; and

(iii) be constructed by methods and practices that minimize flood damage.

(4) The proposed project shall be designed and constructed so that:

(i) it is consistent with the need to minimize flood damage within the flood hazard area;

(ii) all public utilities and facilities, such as sewer, gas, electric and water systems, are located and constructed to minimize or eliminate flood damage; and

(iii) adequate drainage is provided to reduce exposure to flood hazards.

(5) New and replacement water supply systems shall be designed to minimize or eliminate infiltration of floodwaters into the systems.

(6) New and replacement sanitary sewage systems and any other waste disposal systems shall be designed to minimize or eliminate infiltration of floodwaters into the systems, and discharges from the systems into floodwaters, and new and replacement onsite waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.

(7) All new residential structures and substantial improvements of existing residential structures shall have the lowest floor (including basement) elevated to not less than one foot above the base flood level.

(8) All new nonresidential structures and substantial improvements of existing nonresidential structures shall have the lowest floor (including basement) elevated or flood-proofed to not less than one foot above the base flood level, so that below this elevation the structure, together with attendant utility and sanitary facilities, 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.

(9) Where floodproofing is utilized for a particular structure in order to comply with this Part, a professional engineer or architect licensed to practice in New York State shall certify to said State agency 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.

(10) For the purpose of the determination of applicable flood insurance risk premium rates for structures insurable under the National Flood Insurance Program (42 U.S.C. § 4001 et seq.) (see section 503.1 of this Title), said agency shall:

(i) obtain the elevation (in relation to mean sea level) of the lowest habitable floor (including basement) of any new or substantially improved structures, and specify whether or not such structure contains a basement;

(ii) if a structure has been flood-proofed, obtain the elevation (in relation to mean sea level) to which the structure was flood-proofed; and

(iii) maintain records of such information.

(11) In riverine situations, affected cities, towns and villages and the department shall be notified in writing by said State agency prior to any alteration or relocation of a watercourse.

(12) The flood carrying capacity within any altered or relocated portion of any watercourse shall be maintained.

(13) All mobile homes shall be anchored to resist flotation, collapse or lateral movement by providing over-the-top and frame ties to ground anchors as follows:

(i) 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 (except that mobile homes less than 50 feet long shall require only one additional tie per side);

(ii) frame ties shall be provided at each corner of the home, with five additional ties per side at intermediate points (except that mobile homes less than 50 feet long shall require only four additional ties per side);

(iii) all components of the anchoring system shall be capable of carrying a force of 4,800 pounds; and

(iv) any additions to the mobile home shall be similarly anchored.

(14) All mobile homes shall have:

(i) stands or lots that are elevated on compacted fill or on pilings or piers so that the lowest floor of the mobile home will be located not less than one foot above the base flood level;

(ii) adequate surface drainage;

(iii) lots that are large enough to permit steps from the ground into the mobile home and ready access for a hauler;

(iv) in the case of elevation on pilings or piers, pier foundations or pilings that are placed in stable soil no more than 10 feet apart; and

(v) in the case of elevation on piers, adequate reinforcement for piers that extend more than six feet above ground level.

(15) In riverine situations, no project (including fill) shall be undertaken unless it is demonstrated that the cumulative effect of the proposed project, when combined with all other existing and anticipated development, will not increase the existing water surface elevation of the base flood more than one foot at any point. Provided, the provisions of this paragraph shall not apply to any project being undertaken on a site where there is less than one square mile of drainage area for the watercourse involved above such site, and where the administrator has not provided final flood base elevations on a city, town or village's FIRM.

(16) No project (including fill) shall be undertaken unless it is demonstrated that the cumulative effect of the proposed project, when combined with all existing development, will not cause any material flood damage to such existing development.

(17) In order to prevent potential flood damage to certain facilities that would result in serious danger to life and health, or widespread social or economic dislocation, none of the following new projects shall be undertaken within any flood hazard area:

(i) facilities designed for bulk storage of chemicals, petrochemicals, hazardous or toxic substances or floatable materials;

(ii) hospitals, rest homes, correctional facilities, dormitories, patient care facilities;

(iii) major power generation, transmission or substation facilities, except for hydroelectric facilities;

(iv) major communications centers, such as civil defense centers; or

(v) major emergency service facilities, such as central fire and police stations.

(b) When the administrator has provided data for a city, town or village to designate a regulatory floodway and such floodway has been designated by a city, town or village, any State agency proposing to commence any project in a flood hazard area in such city, town or village shall do so only if it determines such project is in compliance with the following criteria:

(1) The requirements of subdivision (a) of this section, except for the provisions of paragraph (15) of said subdivision.

(2) No portion of the project, including encroachments, fill, new construction or substantial improvements, shall be placed or located within the adopted regulatory floodway that would result in any increase in flood levels during the occurrence of the base flood discharge, except where the effect on flood levels, due to the loss of floodway capacity, is completely offset by the creation of equal floodway hydraulic capacity at that point.

(3) There shall be no placement of any mobile homes within the adopted regulatory floodway.

(c) When the administrator has identified coastal high hazard areas on a city, town or village's FIRM, any State agency proposing to commence any project in a coastal high hazard area in such city, town or village shall do so only if it determines such project is in compliance with the following criteria:

(1) The requirements of paragraphs (1) through (10), inclusive, and paragraph (17) of subdivision (a) of this section.

(2) All new structures shall be located landward of the reach of mean high tide.

(3)

(i) All new structures and substantial improvements of existing structures shall be elevated on adequately anchored pilings or columns, and securely anchored to such pilings or columns, so that the lowest portion of the structural members of the lowest floor (excluding the pilings or columns) is elevated to not less than one foot above the base flood level;

(ii) a professional engineer or architect licensed to practice in New York State shall certify to said agency that the structure is securely anchored to adequately anchored pilings or columns in order to withstand high velocity waters and hurricane wave wash; and

(iii) the requirements of subparagraphs (i) and (ii) of this paragraph shall not be applicable to temporary structures associated with recreational uses, or to marine uses such as bridges, docks, jetties, piers, breakwaters or groins.

(4) All new structures and substantial improvements of existing structures shall have the space below the lowest floor free of obstructions or be constructed with breakaway walls intended to collapse under stress without jeopardizing the structural support of the structure, so that the impact on the structure by abnormally high tides or wind-driven water is minimized. Such temporarily enclosed space shall not be used for human habitation.

(5) There shall be no use of fill for structural support of structures.

(6) There shall be no placement of mobile homes.

(7) There shall be no alteration of sand dunes which would increase potential flood damage.

(d) In order to prevent flood damage to certain facilities that would result in serious danger to life and health, or widespread social or economic dislocation, none of the following new projects shall be undertaken by any State agency within any levee-protected area unless the entire project or, where applicable, the lowest floor of such project, is elevated to at least one foot above the base flood level:

(1) facilities designed for bulk storage of chemicals, petrochemicals, hazardous or toxic substances or floatable materials;

(2) hospitals, rest homes, correctional facilities, dormitories, patient care facilities;

(3) major power generation, transmission or substation facilities, except for hydroelectric facilities;

(4) major communications centers, such as civil defense centers;

(5) major emergency service facilities, such as central fire and police stations; or

(6) transportation facilities which provide a major access route to any facility listed in paragraphs (1) through (5) of this subdivision.

N.Y. Comp. Codes R. & Regs. Tit. 6 § 502.4