ARTICLE 23. FLOODPLAIN OVERLAY DISTRICT
23-1. General provisions.
23-2. Definitions.
23-3. Establishment
of zoning district.
23-4. District provisions; generally.
23-5. Variances
(factors to be considered).
23-6.
Existing structures in floodplain districts.
23-7. Enactment.
(a) Authority. The authority to zone to protect floodplains is found in three sections of the Virginia Code. Section 15.1-489 mandates that ordinances and districts "shall be designed to give reasonable considerations to . . . loss of life, health, or property from flood." Section 15.1-490 further provides that "zoning ordinances shall be drawn and applied with reasonable consideration for . . . the preservation of floodplains." Finally, the Flood Damage Reduction Act (Sec. 10.1-600 et seq.) establishes the federal National Flood Insurance Act 42 U.S.C. ' 4001 et seq. as the appropriate reference point for floodplain protection.
(b) Purpose. The purpose of these provisions is to prevent the loss of life and property, the creation of health and safety hazards, the disruption of commerce and governmental services, the extraordinary and unnecessary expenditure of public funds for flood protection and relief, and the impairment of the tax base by:
(1) Regulating uses, activities, and development which, alone or in combination with other existing or future uses, activities, and development, will cause unacceptable increases in flood heights, velocities, and frequencies.
(2) Restricting or prohibiting certain uses, activities, and development from locating within districts subject to flooding.
(3) Requiring all those uses, activities, and developments that do occur in flood-prone districts to be protected and/or flood proofed against flooding and flood damage.
(4) Protecting individuals from buying land and structures which are unsuited for intended purposes because of flood hazards.
(c) Applicability. These provisions shall apply to all lands within the jurisdiction of Lancaster County, Virginia, and identified as being in the 100-year floodplain by the Federal Insurance Administration.
(d) Compliance and liability.
(1) No land shall hereafter be developed and no structure shall be located, relocated, constructed, reconstructed, enlarged, or structurally altered except in full compliance with the terms and provisions of this ordinance and any other applicable ordinances and regulations which apply to uses within the jurisdiction of this ordinance.
(2) The degree of flood protection sought by the provisions of this ordinance is considered reasonable for regulatory purposes and is based on acceptable engineering methods of study. Larger floods may occur on rare occasions. Flood heights may be increased by manmade or natural causes, such as ice jams and bridge openings restricted by debris. This ordinance does not imply that districts outside the floodplain district, or that land uses permitted within such district will be free from flooding or flood damages.
(3) This ordinance shall not create liability on the part of Lancaster County, Virginia or any officer or employee thereof for any flood damages that result from reliance on this ordinance or any administrative decision lawfully made thereunder.
(e) Abrogation and greater restrictions. This ordinance supersedes any ordinance currently in effect in flood-prone districts. However, any underlying zoning district shall remain in full force and effect to the extent that its provisions are more restrictive than this district.
(f) Severability. If any section, subsection, paragraph, sentence, clause, or phrase of this ordinance shall be declared invalid for any reason whatever, such decision shall not affect the remaining portions of this ordinance. The remaining portions shall remain in full force and effect; and for this purpose, the provisions of this ordinance are hereby declared to be severable.
(Ord. of 8-26-93)
Base flood/one-hundred year flood: A flood that, on the average, is likely to occur once every 100 years (i.e., that has a one-percent chance of occurring each year, although the flood may occur in any year).
Base flood elevation (BFE): The Federal Emergency Management Agency designated 100-year water surface elevation as reported in Flood Insurance Study, Lancaster County, Virginia (Unincorporated Areas) 1988, Federal Emergency Management Agency (Community Number 510084).
Breakaway wall: A wall that is not part of the structural support of the building and is intended through its design and construction to the elevated portion of the building or supporting foundation system.
Coastal high hazard area: An area of special flood hazard extending from offshore to the inland limit of a primary frontal dune along an open coast and any other area subject to high velocity wave action from storms or seismic sources.
Development: Any manmade 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.
Floodplain: Any land area susceptible to being inundated by water from any source.
Floodway: 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 a designated height.
Freeboard: A factor of safety usually expressed in feet above a flood level for purposes of floodplain management.
Recreational vehicle: A vehicle which is:
(a) Built on a single chassis;
(b) 400 square feet or less when measured at the largest horizontal projection;
(c) Designed to be self-propelled or permanently towable by a light duty truck; and
(d) Designed primarily not for use as a permanent dwelling but as temporary living quarters for recreational camping, travel, or seasonal use.
Mangrove stand: An assemblage of mangrove trees which are mostly low trees noted for a copious development of interlacing adventitious roots above the ground and which contains one for more of the following species: black mangrove (avicennia Nitida): red mangrove (Khizophora Mangle); white mangrove (Languncularia Racemosa); and buttonwood (Conocarpus Erecta).
Primary frontal dune: A continuous or nearly continuous mound or ridge of sand with relatively steep seaward and landward slopes immediately landward and adjacent the beach and overtopping from high tides and waves during major coastal storms. The inland limit of the primary frontal dune occurs at the point where there is distinct change from a relatively steep slope to a relatively mild slope.
Substantial damage: Damage of any origin sustained by a structure whereby the cost of restoring the structure to its before damaged condition would equal or exceed 50 percent of the market value of the structure before the damage occurred.
Substantial Improvement: Any reconstruction, rehabilitation, addition, or other improvement of a structure, the cost of which equals or exceeds 50 percent of the market value of the structure before the "start of construction" of the improvement. This term includes structures which have incurred "substantial damage" regardless of the actual repair work performed. The term does not, however, include either: (1) any project for improvement of a structure to correct existing violations of state or local health, sanitary, or safety code specifications which have been identified by the local code enforcement official and which are the minimum necessary to assure safe living conditions or (2) any alteration of a "historic structure," provided that the alteration will not preclude the structures continued designation as a "historic structure."
(Ord. of 8-26-93; Ord. of 10-95)
23-3. Establishment of zoning districts.
(a) Description of district.
(1) Basis of district. The floodplain district shall include areas subject to inundation by waters of the 100-year flood. The basis for the delineation of the district shall be the 100-year flood elevations or profiles contained in the Flood Insurance Study (FIS) and the Flood Insurance Rate Maps (FIRMs) for Lancaster County, Virginia prepared by the Federal Emergency Management Agency, Federal Insurance Administration, dated March 4, 1988, as amended.
The approximated floodplain district shall be that floodplain area for which no detailed flood profiles or elevations are provided by where a 100-year flood boundary has been approximated. Such areas are shown as Zone A on the maps accompanying the Flood Insurance Study. For these areas, the 100-year flood elevations and floodway information from federal, state, and other acceptable sources shall be used, when available. Where the specific 100-year flood elevation cannot be determined for this area using other sources of data, such as the U.S. Army Corps of Engineers Floodplain Information Reports, U.S. Geological Survey Flood-Prone Quadrangles, etc., then the applicant for the proposed use, development and/or activity shall determine this elevation in accordance 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 review by the zoning administrator.
(2) Overlay concept.
a. The floodplain district described above shall be overlays to the existing underlying area as shown on the Official Zoning Ordinance Map, and as such, the provisions for the floodplain district shall serve as a supplement to the underlying district provisions.
b. Any conflict between the provisions or requirements of the floodplain districts and those of any underlying district, the more restrictive provisions and/or those pertaining to the floodplain districts shall apply.
c. In the event any provision concerning a floodplain district is declared inapplicable as a result of any legislative or administrative actions or judicial decision, the basic underlying provisions shall remain applicable.
(b) Official zoning map. The boundaries of the floodplain district are established as shown on the flood insurance rate map which is declared to be a part of this ordinance and which shall be kept on file at the Lancaster County land use offices.
(c) District boundary changes. The delineation of any of the floodplain district may be revised by the Lancaster County Board of Supervisors where natural or manmade changes have occurred and/or where more detailed studies have been conducted or undertaken by the U. S. Army Corps of Engineers or other qualified agency, or an individual documents the need for such change. However, prior to any such change, approval must be obtained from the Federal Insurance Administration.
(d) Interpretation of district boundaries. Initial interpretations of the boundaries of the floodplain district shall be made by the zoning administrator. Should a dispute arise concerning the boundaries of any of the districts, the board of zoning appeals shall make the necessary determination. The person questioning or contesting the location of the district boundary shall be given a reasonable opportunity to present his case to the board and to submit technical evidence if desired.
(Ord. of 8-26-93; Ord. of 10-95)
(a) Coastal high hazard areas. These areas have special flood hazards associated with wave action; therefore the following additional provisions shall apply:
(1) All new construction shall be located 100 feet landward of the reach of mean high tide.
(2) There shall be no fill used as structural support.
(3) There shall be no alteration of sand dunes or mangrove stands which would increase potential flood damage.
(4) Within V-Zones on the Flood Insurance Rate Map, obtain the elevation (in relation to mean sea level) of the bottom of the lowest horizontal structural member of the lowest floor (excluding pilings and columns) of all new and substantially improved structures, and whether or not such structures contain a basement.
(5) All new construction and substantial improvements elevated on pilings and columns must have the bottom of the lowest horizontal structural member of the lowest floor (excluding the pilings or columns) elevated to or above the base flood level and the pile or column foundation and structure attached thereto must be anchored to resist floatation, collapse and lateral movement due to the effects of wind and water loads acting simultaneously on all building components. Water loading values used shall be those associated with the base flood. Wind loading values used shall be those required by applicable state or local building standards. A registered professional engineer or architect shall develop or review the structural design and methods of construction and shall certify that design and methods of construction to be used are in accordance with accepted standards.
(6) Provide that all new construction and substantial improvements, within zones V1-30 and V on the community's FIRM, have the space below the lowest floor either free of obstruction or constructed with nonsupporting breakaway walls, open wood lattice work, or insect screening intended to collapse, displacement, or other structural damage to the elevated portion of the building or supporting foundation system. For the purpose of this section, a breakaway wall shall have a design stage loading resistance of 20 pounds per square foot (either by design or when so required by local or state codes) may be permitted only if a registered professional engineer or architect certifies that the designs proposed meet the following conditions:
1. Breakaway wall collapse shall result from a water load less than which would occur during the base flood; and
2. The elevated portion of the building and supporting foundation shall not be subject to collapse, displacement, or other structural damage due to the effects of wind and water loads acting simultaneously on all building components (structural and nonstructural). Water loading values used shall be those required by applicable state or local building standards. Such enclosed space shall be usable solely for parking of vehicles, building access or storage.
(7) All manufactured homes to be placed or substantially improved within V-Zones shall comply with the same standards as set forth for conventional housing in V-Zones.
(8) All recreational vehicles placed in V-Zones either be (1) on site for fewer than 180 consecutive days, (2) be fully licensed and ready for highway use, or (3) meet the same standards as for conventional housing in V-Zones.
(b) Permit requirement. All uses, activities, and development occurring within any floodplain district shall be undertaken only upon the issuance of a zoning permit. Such development shall be undertaken only in strict compliance with the provisions of the ordinance and with all other applicable codes and ordinances, such as the Virginia Uniform Statewide Building Code and the Lancaster County Subdivision Ordinance. Prior to the issuance of any such permit, the zoning administrator shall require all applications to include compliance with all applicable state and federal laws. Under no circumstances shall any use, activity, and/or development adversely affect the capacity of the channels or floodway of any watercourse, drainage ditch, or any other drainage facility or system.
(c) Alteration or relocation of watercourse. Prior to any proposed alteration or relocation of any channels or of any watercourse, stream, etc., within this jurisdiction a permit shall be obtained from the U.S. Corps of Engineers, the Virginia Department of Environmental Quality, and the Virginia Marine Resources Commission (a joint permit application is available from any of these organizations). Furthermore, notification of the proposal shall be given by the applicant to all affected adjacent jurisdictions, the Division of Soil and Water Conservation (Department of Conservation and Recreation), and the Federal Insurance Administration.
(d) Drainage facilities. Storm drainage facilities shall be designed to convey the flow of storm water runoff in a safe and efficient manner. The system shall insure proper drainage along streets, and provide positive drainage away from buildings. The system shall also be designed to prevent the discharge of excess runoff onto adjacent properties.
(e) Site plans and permit applications. All applications for development in the floodplain district and all building permits issued for the floodplain shall incorporate the following information:
(1) For structures to be elevated, the elevation of the lowest floor (including basement).
(2) For structures to be floodproofed (nonresidential only), the elevation to which the structure will be floodproofed.
(3) The elevation of the 100-year flood.
(4) Topographic information showing existing and proposed ground elevations.
(f) Encroachment provisions.
(1) No new construction or development shall be permitted within the floodplain district unless it is demonstrated that the cumulative effect of the proposed development, when combined with all other existing and anticipated development, will not increase the 100-year flood elevation more than one foot at any point.
(2) 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 analyses performed in accordance with standard engineering practice that the proposed encroachment would not result in any increase in the 100-year flood elevation.
(g) Recreational vehicles. Recreational vehicles placed on sites shall be in compliance with Article 19 - Major Recreational Vehicles of the Lancaster County Zoning Ordinance and:
(1) Be on the site for fewer than 180 consecutive days, be fully licensed and ready for highway use; or
(2) Meet the permit requirements for placement and the elevation and anchoring requirements for manufactured homes as contained in the Uniform Statewide Building Code.
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.
(Ord. of 8-26-93; Ord. of 10-95)
23-5. Variances (factors to be considered).
In passing upon applications for variances, the board of zoning appeals shall satisfy all relevant factors and procedures specified in other sections of the zoning ordinance and consider the following additional factors:
(a) The danger to life and property due to increased flood heights or velocities caused by encroachments. No variance shall be granted for any proposed use, development, or activity within any floodway that will cause any increase in the 100-year flood elevation.
(b) The danger that materials may be swept on to other lands or downstream to the injury of others.
(c) The proposed water supply and sanitation systems and the ability of these systems to prevent disease, contamination, and unsanitary conditions.
(d) The susceptibility of the proposed facility and its contents to flood damage and the effect of such damage on the individual owners.
(e) The importance of the services provided by the proposed facility to the community.
(f) The requirements of the facility for a waterfront location.
(g) The availability of alternative locations not subject to flooding for the proposed use.
(h) The compatibility of the proposed use with existing development and development anticipated in the foreseeable future.
(i) The relationship of the proposed use to the comprehensive plan and floodplain management program for the area.
(j) The safety of access by ordinary and emergency vehicles to the property in time of flood.
(k) The expected heights, velocity, duration, rate of rise, and sediment transport of the flood waters expected at the site.
(l) The repair or rehabilitation of historic structures upon a determination that the proposed repair or rehabilitation will not preclude the structure's continued designation as a historic structure and the variance is the minimum necessary to preserve the historic character and design of the structure.
(m) Such other factors which are relevant to the purposes of this ordinance.
The board of zoning appeals may refer any application and accompanying documentation pertaining to any request for a variance to any engineer or other qualified person or agency for technical assistance in evaluating the proposed project in relation to flood heights and velocities, and the adequacy of the plans for flood protection and other related matters.
Variances shall be issued only after the board of zoning appeals has determined that the granting of such will not result in (a) unacceptable or prohibited increases in flood heights, (b) additional threats to public safety, (c) extraordinary public expense; and will not (d) create nuisances, (e) cause fraud or victimization of the public, or (f) conflict with local laws or ordinances. Variances shall be issued only after the board of zoning appeals has determined that variance will be the minimum required to provide relief from any hardship to the applicant.
The board of zoning appeals shall notify the applicant for a variance, in writing, that the issuance of a variance to construct a structure below the 100-year flood elevation (a) increases the risks to life and property and (b) will result in increased premium rates for flood insurance.
A record shall be maintained of the above notification as well as all variance actions, including justification for the issuance of the variances. Any variances which are issued shall be noted in the annual or biennial report submitted to the Federal Insurance Administrator.
(Ord. of 8-26-93)
23-6. Existing structures in floodplain districts.
A structure or use of a structure or premises which lawfully existed before the enactment of these provisions, but which is not in conformity with these provisions, may be continued subject to the following conditions:
(a) Existing structures in the floodway area shall not be expanded or enlarged unless it has been demonstrated through hydrologic and hydraulic analyses performed in accordance with standard engineering practice that the proposed expansion would not result in any increase in the 100-year flood elevation.
(b) Any modifications, alteration, repair, reconstruction, or improvement of any kind to a structure and/or use located in any floodplain area to an extent or amount of less than 50 percent of its market value, shall be elevated and/or flood proofed to the greatest extent possible.
(c) The modification, alteration, repair, reconstruction, or improvement of any kind to a structure and/or use, regardless of its locations in a floodplain area, to an extent or amount of 50 percent or more of its market value shall be undertaken only in full compliance with the provisions of this ordinance and the Virginia Uniform Statewide Building Code.
(Ord. of 8-26-93)
Enacted and ordained this 26th day of August, 1993. This ordinance shall become effective upon passage.
(Ord. of 8-26-93)