Mansfield City Zoning Code
ARTICLE 10
Flood Hazard Regulations
§ 190-70 Flood hazard areas
A.
General.
(1)
Land which is designated as a flood hazard area, land within flood encroachment lines administered by the State Department of Environmental Protection, and other land subject to 100-year flooding (Base Flood) shall not be built upon, nor shall it be used for residential occupancy, but, subject to the prior receipt of special permit approval from the Planning and Zoning Commission, these areas may be used for those uses identified in § 190-9. Maps and other information depicting areas subject to flooding are available for review in the Town's Planning Office.
(2)
When base flood elevation data or floodway data have not been provided through the Town's "Flood Insurance Study" and "Floodway" and "Flood Insurance Rate" maps, the Commission shall consider any available data from other sources, provided such information shall be satisfactory to the Commission and the Mansfield Department of Public Works. For the purposes of these Regulations, all areas depicted as zone "A" on the Town's Flood Insurance Rate Map" are designated as regulated floodways.
B. BASE FLOOD BASEMENT DEVELOPMENT FLOOD BOUNDARY AND FLOODWAY MAP (FLOODWAY) FLOOD HAZARD AREA FLOOD INSURANCE RATE MAP (FIRM) FLOOD INSURANCE STUDY (FIS) FLOOD-PROOFED FLOODWAY LOWEST FLOOR MANUFACTURED HOME (also known as "mobile home") NEW CONSTRUCTION RECREATIONAL VEHICLE (also known as a "trailer")(1) (2) (3) (4) START of CONSTRUCTION SUBSTANTIAL IMPROVEMENT(1) (2) (3) WATER SURFACE ELEVATION
Definitions. The following definitions are provided for use in conjunction with the flood hazard area provisions of § 190-70 of these Regulations. The definitions in this section shall be utilized only for issues involving flood hazard areas.
The flood having a 1% chance of being equaled or exceeded in any given year.
That portion of a building having its floor sub-grade (below ground level) on all sides.
Any man-made change to improved or unimproved real estate, including, but not limited to buildings or other structures, mining, dredging, filling, grading, paving, excavation or drilling operations or storage of equipment or materials.
The official map of a community on which the Federal Emergency Management Agency has delineated the boundaries of the floodway.
The land within a community subject to a 1% or greater chance of flooding in any given year. Flood hazard areas include areas subject to 100-year flooding as shown on the Federal Emergency Management Agency "Flood Insurance Study," "Floodway" and "Flood Insurance Rate Maps" effective January 2, 1981 and further revisions. The maps and study are adopted by reference and declared to be part of this regulation.
An official map of a community on which the Federal Emergency Management Agency has delineated both the areas of special flood hazard and the risk premium zones applicable to the community.
The official report from the Federal Emergency Management Agency (FEMA), which contains examination, evaluation and determination of flood hazards and, if appropriate, corresponding water surface elevations.
Is defined as water-tight with walls substantially impermeable to the passage of water and with structural components having the capability of resisting hydrostatic and hydrodynamic loads and the effects of buoyancy.
The channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water surface elevation more than one foot.
The lowest floor of the lowest enclosed area (including basement). An unfinished or flood-resistant enclosure, usable solely for parking of vehicles, building access or storage, in an area other than a basement area is not considered a building's lowest floor.
A structure transportable in one or more sections, which is built on a permanent chassis and is designed for use with or without a permanent foundation when attached to the required utilities. The term "manufactured home" does not include a "recreational vehicle."
Structures for which the "start of construction" commenced on or after the effective date of the initial FIRM (January 2, 1981) and includes any subsequent improvements to such structures.
A vehicle which is:
Built on a single chassis;
Four hundred square feet or less when measured at the longest horizontal projections;
Designed to be self-propelled or permanently tow able by a light-duty truck; and
Designed primarily not for use as a permanent dwelling, but as temporary living quarters for recreational, camping, travel or seasonal use.
Includes substantial improvement, and means the date the building permit was issued, provided the actual start of construction, repair, reconstruction, rehabilitation, addition, placement, or other improvement was within 180 days of the permit date. The actual start means either the first placement of permanent construction of a structure on a site, or any work beyond the stage of excavation. For a substantial improvement, the actual start of construction means the first alteration of the building, whether or not that alteration affects the external dimensions of the building.
Any combination of repairs, reconstruction, alteration, or improvements to a structure taking place over a one-year period, in which the cumulative cost equals or exceeds 50% of the market value of the structure. The market value of the structure should be:
For the purposes of this definition, "substantial improvement" is considered to occur when the first alteration of any wall, ceiling, floor, or other structural part of the building commences, whether or not that alteration affects the external dimensions of the structure. The term does not, however, include any project for improvement of a structure required to comply with existing health, sanitary, or safety code specifications, which are solely necessary to assure safe living conditions.
Use of the above-noted cost approach to value method to determine market value is based on the value of the bare land plus the depreciated replacement cost of the structure, using current rates for material, equipment, and labor. It generally results in the highest market value for the property.
The height in relation to the National Geodetic Vertical Datum (NGVD) of 1929 (or other datum, where specified) of floods of various magnitudes and frequencies in the floodplains of coastal or riverine areas.
§ 190-71 Flood hazard zone uses.
The uses listed below in separate categories are permitted in the Flood Hazard Zones provided the provisions of § 190-72 are met and provided special permit approval is obtained in accordance with the provisions of § 190-74.
A.
Agricultural and horticultural uses such as dairies and the keeping of farm animals, field crops, orchards, greenhouses, fish harvesting, and accessory buildings, etc., provided the provisions of § 190-65, § 190-66 and all Special Permit Requirements for Farm Wineries, Farm Breweries and Farm Distilleries are met, but specifically excluding commercial caged poultry or caged livestock operations and other intense commercial agricultural uses and the production or processing of fertilizers, forest, or mineral products;
B.
Open Space Recreational Uses;
C.
Parking Areas;
D.
Accessory buildings as per the provisions of § 190-9G;
E.
Sand and Gravel removal or fill operations as per the provisions of § 190-9K;
F.
Hydropower Facilities;
G.
Swimming pools as per the provisions of § 190-9N.
§ 190-72 Flood hazard area requirements.
A.
Procedure.
(1)
Before a special permit may be granted for use of the above-referenced area, the owner shall submit an application, fee, and site plan in accordance with the provisions of § 190-74. In addition wherever applicable, the submitted site plan shall include the following:
(a)
Elevation in relation to mean sea level of the proposed lowest floor (including basement) of all structures;
(b)
Elevation in relation to mean sea level to which any non-residential structure will be flood-proofed;
(c)
Description of the extent to which any watercourse will be altered or relocated as a result of proposed development;
(d)
A statement as to whether or not the proposed alterations to an existing structure meet the criteria of the substantial improvement definition.
The owner may also be required to submit other data necessary to review the proposal accurately with respect to approval criteria. |
(2)
Upon receipt of an application and other required information, the Commission shall schedule a legally advertised Public Hearing on the proposed activity. Upon completion of the Public Hearing, the application may be approved, denied or approved with modification.
B.
Approval criteria. No development plan shall be approved which is inconsistent with the public welfare, which impairs the integrity of these Regulations, or which does not fully safeguard the use of the land in the immediate neighborhood. No special permit shall be granted until the findings contained in § 190-74 of these Regulations and the following criteria are met to the Commission's satisfaction.
(1)
No structures to be used for residential occupancy are allowed within designated Flood Hazard Areas. The lowest floor elevation, including basement, of all non-residential structures located within designated flood hazard areas shall be elevated to at least one foot above the base flood level (100-year flood level) or be flood-proofed with structural certification by a registered professional engineer or architect certifying that the building will withstand a flood equivalent to the 100-year storm without damage.
(2)
In all Flood Hazard Areas and areas subject to a base flood, any new construction or any substantial improvements shall be:
(a)
Anchored to prevent flotation, collapse or lateral movement of the structure; and
(b)
Constructed with materials resistant to flood damage; and
(c)
Constructed by methods and practices that minimize flood damage; and
(d)
Constructed with electrical, heating, ventilation, plumbing, air conditioning equipment and other service facilities that are designed and/or located so as to prevent water from entering or accumulating within the components during conditions of flooding.
(3)
All existing manufactured homes to be replaced or to be substantially improved shall be elevated so that the lowest floor is at least one foot above the base flood elevation. It 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.
(4)
All recreational vehicles placed on sites within flood hazard areas shall be fully licensed and ready for highway use (a recreational vehicle is ready for highway use if it is on its wheels or jacking system, is attached to the site only by quick-disconnect-type utilities and security devices, and has no permanently-attached additions.)
(5)
Enclosed areas below base flood elevation.
(a)
New construction or substantial improvements to buildings that include fully-enclosed areas formed by foundation and other exterior walls below the base flood elevation shall be designed to preclude finished living space and designed to allow for the entry and exit of floodwaters to automatically equalize hydrostatic flood forces on exterior walls.
(b)
Designs for complying with this requirement must either be certified by a professional engineer or architect or meet the following minimum criteria:
[1]
Provide a minimum of two openings having a total net area of not less than one square inch for every square foot of enclosed area subject to flooding;
[2]
The bottom of all openings shall be no higher than one foot above grade; and
[3]
Openings may be equipped with screens, louvers, valves or other coverings or devices, provided they permit the automatic flow of floodwaters in both directions.
(6)
Within designated floodways, including zone A as designated in the Flood Insurance Rate Map, all development is prohibited, unless it has been demonstrated through hydrologic and hydraulic analyses performed in accordance with standard engineering practice that the proposed development would not result in any increase in flood levels within the community during the occurrence of the base flood discharge. The Town may request floodway data of an applicant for watercourses without FEMA-published floodways. When such data are provided by an applicant or whenever such data are available from any other source (in response to the Town's request or not), the Town shall adopt a regulatory floodway based on 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.
(7)
New and replacement water supply systems shall be designed to minimize or eliminate infiltration of flood waters into the system. New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of flood waters into the system and discharges from the system into flood waters. On-site waste disposal systems shall be located and constructed to avoid impairment to them or contamination from them, during flooding. All applicable provisions of the Connecticut State Health Code shall also be met.
(8)
All work within special flood hazard areas is also subject to regulation under the Inland Wetland Regulations.
(9)
All necessary Federal and State permits shall be obtained by the applicant. Adjacent communities and the Department of Energy and Environmental Protection, Water Resources Unit, shall be notified prior to any alteration or relocation of a watercourse. All work within altered or relocated areas must be maintained so that the flood-carrying capacity is not diminished.
C.
Certifications, record.
(1)
A certification by a registered land surveyor shall be provided after the completion of construction of any new or substantially improved structure, stating the elevation above mean sea level of the lowest floor of the building, including basement, before a Certificate of Zoning Compliance shall be issued.
(2)
A file of all such certifications and flood-proofing certifications will be maintained for public inspection in the office of the Zoning Agent.