Chapter 50
FLOODS*

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Cross references: Buildings and building regulations, ch. 22; environment, ch. 42; planning, ch. 62; streets, sidewalks and other public places, ch. 74; zoning, app. A; subdivisions, app. B; utilities, ch. 86.

State law references: Georgia Safe Dams Act of 1978, O.C.G.A. § 12-5-370 et seq.; construction and operation of watershed and flood control projects by counties, O.C.G.A. § 22-3-100 et seq.

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Article I. In General

Secs. 50-1? 50-30. Reserved.

Article II. Flood Damage Prevention

Division 1. Generally

Sec. 50-31. Findings of fact.

Sec. 50-32. Statement of purpose.

Sec. 50-33. Objectives.

Sec. 50-34. Definitions.

Sec. 50-35. Applicability.

Sec. 50-36. Basis for establishing the areas of special flood hazard.

Sec. 50-37. Development permit.

Sec. 50-38. Compliance.

Sec. 50-39. Abrogation and greater restrictions.

Sec. 50-40. Interpretation.

Sec. 50-41. Warning and disclaimer of liability.

Sec. 50-42. Violation; penalty.

Secs. 50-43? 50-65. Reserved.

Division 2. Administration

Sec. 50-66. Designation of administrator.

Sec. 50-67. Duties and responsibilities of administrator.

Sec. 50-68. Permit procedures.

Sec. 50-69. Variance.

Secs. 50-70? 50-90. Reserved.

Division 3. Flood Hazard Reduction

Sec. 50-91. Generally.

Sec. 50-92. Specific standards.

Sec. 50-93. Streams without established base flood elevation and/or floodways.

Sec. 50-94. Subdivision proposals.

Sec. 50-95. Areas of shallow flooding (AO zones).

ARTICLE I.
IN GENERAL

Secs. 50-1? 50-30. Reserved.

ARTICLE II.
FLOOD DAMAGE PREVENTION

DIVISION 1.
GENERALLY

Sec. 50-31. Findings of fact.

(a) The flood hazard areas of the city are subject to periodic inundation which results in loss of life and property, health and safety hazards, disruption of commerce and governmental services, extraordinary public expenditures for flood protection and relief, and impairment of the tax base, all of which adversely affect the public health, safety and general welfare.

(b) Flood losses are caused by the cumulative effect of obstructions in floodplains causing increases in flood heights and velocities, and by the occupancy in flood hazard areas by uses vulnerable to floods or hazardous to other lands which are inadequately elevated, floodproofed or otherwise unprotected from flood damages.

(Ord. of 1-2-1990, art. I, § B)

Sec. 50-32. Statement of purpose.

It is the purpose of this chapter to promote the public health, safety and general welfare, and to minimize public and private losses due to flood conditions in specific areas by provisions designed to:

(1) Restrict or prohibit uses which are dangerous to health, safety and property due to water or erosion hazards, or which result in damaging increases in erosion or in flood heights or velocities;

(2) Require that uses vulnerable to floods, including facilities which serve such uses, be protected against flood damage at the time of initial construction;

(3) Control the alteration of natural floodplains, stream channels and natural protective barriers which are involved in the accommodation of floodwaters;

(4) Control filling, grading, dredging and other development which may increase erosion or flood damage; and

(5) Prevent or regulate the construction of flood barriers which will unnaturally divert floodwaters or which may increase flood hazards to other lands.

(Ord. of 1-2-1990, art. I, § C)

Sec. 50-33. Objectives.

The objectives of this chapter are to:

(1) Protect human life and health;

(2) Minimize expenditure of public money for costly flood control projects;

(3) Minimize the need for rescue and relief efforts associated with flooding and generally undertaken at the expense of the general public;

(4) Minimize prolonged business interruptions;

(5) Minimize damage to public facilities and utilities such as water and gas mains, electric, telephone and sewer lines, and streets and bridges located in floodplains;

(6) Help maintain a stable tax base by providing for the sound use and development of floodprone areas in such a manner as to minimize flood blight areas; and

(7) Ensure that potential home buyers are notified that property is in a flood area.

(Ord. of 1-2-1990, art. I, § D)

Sec. 50-34. Definitions.

The following words, terms and phrases, when used in this chapter, shall have the meanings ascribed to them in this section, except where the context clearly indicates a different meaning:

Addition to an existing building means any walled and roofed expansion to the perimeter of a building in which the addition is connected by a common loadbearing wall other than a fire wall. Any walled and roofed addition which is connected by a fire wall or is separated by independent perimeter loadbearing walls is new construction.

Appeal means a request for a review of the building official's interpretation of any provision of this chapter, or a request for a variance.

Area of shallow flooding means a designated AO or VO zone on a community's flood insurance rate map (FIRM) with base flood depths from one to three feet where a clearly defined channel does not exist, where the path of flooding is unpredictable and indeterminate and where velocity flow may be evident.

Area of special flood hazard means the land in the floodplain within a community subject to a one percent or greater chance of flooding in any given year.

Base flood means the flood having a one percent chance of being equaled or exceeded in any given year.

Basement means that portion of a building having its floor subgrade (below ground level) on all sides.

Breakaway wall means a wall that is not part of the structural support of the building and is intended, through its design and construction, to collapse under specific lateral loading forces without causing damage to the elevated portion of the building or the supporting foundation system.

Building means any structure built for support, shelter or enclosure for any occupancy or storage.

Coastal high hazard area means the area subject to high velocity waters caused by, but not limited to, hurricane wave wash. The area is designated on a flood insurance rate map as zone V1? 30, VE or V.

Development means any manmade change to improved or unimproved real estate, including, but not limited to, buildings or other structures, mining, dredging, filling, grading, paving, excavating, drilling operations or permanent storage of materials or equipment.

Elevated building means a nonbasement building built to have the lowest floor elevated above the ground level by means of fill, solid foundation perimeter walls, pilings, columns (posts and piers), shear walls or breakaway walls.

Existing construction means any structure for which the start of construction commenced before November 3, 1980.

Existing manufactured home park or subdivision means a manufactured home park or subdivision for which the construction of facilities for servicing the lots on which the manufactured homes are to be affixed, including, at a minimum, the installation of utilities, the construction of streets and either final site grading or the pouring of concrete pads, is completed before the effective date of the floodplain management regulations adopted by the city council on November 3, 1980.

Expansion to an existing manufactured home park or subdivision means the preparation of additional sites by the construction of facilities for servicing the lots on which the manufactured homes are to be affixed, including the installation of utilities, the construction of streets and either final site grading or the pouring of concrete pads.

Flood or flooding means a general and temporary condition of partial or complete inundation of normally dry land areas from the:

(1) Overflow of inland or tidal waters;

(2) Unusual and rapid accumulation or runoff of surface waters from any source.

Flood hazard boundary map (FHBM) means an official map of a community issued by the Federal Emergency Management Agency, where the boundaries of the areas of special flood hazard have been defined as zone A.

Flood insurance rate map (FIRM) means 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.

Flood insurance study means the official report provided by the Federal Emergency Management Agency. The report contains flood profiles as well as the flood boundary floodway map and the water surface elevation of the base flood.

Floodplain means any land area susceptible to flooding.

Floodway means 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.

Functionally dependent facility means a facility which cannot be used for its intended purpose unless it is located or carried out in close proximity to water, such as a docking or port facility necessary for the loading and unloading of cargo or passengers, shipbuilding, ship repair or seafood processing facilities. The term does not include longterm storage, manufacture, sales or service facilities.

Highest adjacent grade means the highest natural elevation of the ground surface, prior to construction, next to the proposed walls of a building.

Historic structure means any structure that is:

(1) Listed individually in the National Register of Historic Places (a listing maintained by the department of interior) or preliminarily determined by the secretary of the interior as meeting the requirements for individual listing on the National Register of Historic Places;

(2) Certified or preliminarily determined by the secretary of the interior as contributing to the historical significance of a registered historic district or a district preliminarily determined by the secretary of the interior to qualify as a registered historic district;

(3) Individually listed on a state inventory of historic places in states with historic preservation programs which have been approved by the secretary of the interior; or

(4) Individually listed on a local inventory of historic places in communities with historic preservation programs that have been certified either:

a. By an approved program as determined by the secretary of the interior; or

b. Directly by the secretary of the interior in states without approved programs.

Lowest floor means the lowest floor of the lowest enclosed area, including basement. An unfinished or flood resistant enclosure, used solely for parking of vehicles, building access, or storage, in an area other than a basement, is not considered a building's lowest floor, provided that such enclosure is not built so as to render the structure in violation of other provisions of this Code.

Manufactured home means a building, transportable in one or more sections, which is built on a permanent chassis and designed to be used with or without a permanent foundation when connected to the required utilities. The term also includes park trailers, travel trailers and similar transportable structures placed on a site for 180 consecutive days or longer and intended to be improved property.

Mean sea level means the average height of the sea for all stages of the tide. The term is used as a reference for establishing various elevations within the floodplain. For purposes of this chapter, the term is synonymous with National Geodetic Vertical Datum (NGVD).

National Geodetic Vertical Datum (NGVD), as corrected in 1929, is a vertical control used as a reference for establishing varying elevations within the floodplain.

New construction means any structure for which the start of construction commenced after November 3, 1980. The term also includes any subsequent improvements to such structure.

New manufactured home park or subdivision means a manufactured home park or subdivision for which the construction of facilities for servicing the lots on which the manufactured homes are to be affixed, including, at a minimum, the installation of utilities, the construction of streets and their final site grading or the pouring of concrete pads, is completed on or after the effective date of floodplain management regulations adopted by a community.

Recreational vehicle means a vehicle which is:

(1) Built on a single chassis;

(2) Four hundred square feet or less when measured at the largest horizontal projection;

(3) Designed to be self-propelled or permanently towable by a light duty truck; and

(4) Designed primarily not for use as a permanent dwelling but as temporary living quarters for recreational, camping, travel or seasonal use.

Start of construction (for other than new construction or substantial improvements under the Coastal Barrier Resources Act (PL 97-348)), includes substantial improvement, and means the date the building permit was issued, provided the actual start of construction, repair, reconstruction or improvement was within 180 days of the permit date. The actual start means the first placement of permanent construction of a building, including a manufactured home, on a site, such as the pouring of slabs or footings, installation of piles, construction of columns, or any work beyond the stage of excavation or the placement of a manufactured home on a foundation. Permanent construction does not include land preparation, such as clearing, grading and filling; nor does it include the installation of streets and/or walkways; nor does it include excavation for a basement, footings, piers or foundations or the erection of temporary forms; nor does it include the installation on the property of accessory buildings, such as garages or sheds not occupied as dwelling units or not part of the main building. For a substantial improvement, the actual start of construction means the first alteration of any wall, ceiling, floor or other structural part of a building, whether or not that alteration affects the external dimensions of the building.

Structure means a walled and roofed building that is principally above ground, a manufactured home, a gas or liquid storage tank or other manmade facilities or infrastructures.

Substantial damage means damage of any origin sustained by a structure where 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 means any combination of repairs, reconstruction, alteration or improvement to a building, taking place during the life of a building (a 50 year period), in which the cumulative cost equals or exceeds 50 percent of the market value of the building. The market value of the building should be:

(1) The appraised value of the building prior to the start of the initial repair or improvement; or

(2) In the case of damage, the value of the building prior to the damage occurring.

This term includes structures which have incurred substantial damage, regardless of the actual repair work performed. 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 building. The term does not, however, include any project for improvement of a building required to comply with existing health, sanitary or safety code specifications which have been identified by the code enforcement official and which are solely necessary to assure safe living conditions.

Substantially improved existing manufactured home parks or subdivisions means where the repair, reconstruction, rehabilitation or improvement of the streets, utilities and pads equals or exceeds 50 percent of the value of the streets, utilities and pads before the repair, reconstruction or improvement commenced.

Variance means a grant of relief from the requirements of this chapter which permits construction in a manner otherwise prohibited by this chapter where specific enforcement would result in unnecessary hardship.

(Ord. of 1-2-1990, art. 2; Ord. of 7-12-2003, § I)

Cross references: Definitions generally, § 1-2.

Sec. 50-35. Applicability.

This chapter shall apply to all areas of special flood hazard within the jurisdiction of the city.

(Ord. of 1-2-1990, art. 3, § A)

Sec. 50-36. Basis for establishing the areas of special flood hazard.

The areas of special flood hazard identified by the Federal Emergency Management Agency in its report dated January 1981, with accompanying maps and other supporting data, and any revision thereto, are adopted by reference and declared to be a part of this chapter.

(Ord. of 1-2-1990, art. 3, § B)

Sec. 50-37. Development permit.

A development permit shall be required in conformance with the provisions of this chapter prior to the commencement of any development activities.

(Ord. of 1-2-1990, art. 3, § C)

Sec. 50-38. Compliance.

No structure or land shall be located, erected, converted or structurally altered without full compliance with the terms of this chapter and other applicable regulations.

(Ord. of 1-2-1990, art. 3, § D)

Sec. 50-39. Abrogation and greater restrictions.

This chapter is not intended to repeal, abrogate or impair any existing easements, covenants or deed restrictions; however, where this chapter and another conflict or overlap, whichever imposes the more stringent restrictions shall prevail.

(Ord. of 1-2-1990, art. 3, § E)

Sec. 50-40. Interpretation.

In the interpretation and application of this chapter all provisions shall be:

(1) Considered as minimum requirements;

(2) Liberally construed in favor of the governing body; and

(3) Deemed neither to limit nor repeal any other powers granted under state statutes.

(Ord. of 1-2-1990, art. 3, § F)

Sec. 50-41. Warning and disclaimer of liability.

The degree of flood protection required by this chapter is considered reasonable for regulatory purposes and is based on scientific and engineering consideration. Larger floods can and will occur on rare occasions. Flood heights may be increased by manmade or natural causes. This chapter does not imply that land outside the areas of special flood hazard or uses permitted within such areas will be free from flooding or flood damage. This chapter shall not create liability on the part of the city or by any officer or employee thereof for any flood damage that results from reliance on this chapter or any administrative decision lawfully made under this chapter.

(Ord. of 1-2-1990, art. 3, § G)

Sec. 50-42. Violation; penalty.

Violation of the provisions of this chapter, or failure to comply with any of the requirements of this chapter, including violation of conditions and safeguards established in connection with grants of variance or special exceptions, shall constitute a misdemeanor. Any person who violates this chapter or fails to comply with any requirements of this chapter shall, upon conviction thereof, shall be punished as set forth in section 1-12, and in addition, shall pay all costs and expenses involved in the case. Each day such violation continues shall be considered a separate offense. Nothing contained in this section shall prevent the city from taking such other lawful action as is necessary to prevent or remedy any violation of this chapter.

(Ord. of 1-2-1990, art. 3, § H)

Secs. 50-43? 50-65. Reserved.

DIVISION 2.
ADMINISTRATION*

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Cross references: Administration, ch. 2.

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Sec. 50-66. Designation of administrator.

The building official is appointed to administer and implement the provisions of this chapter.

(Ord. of 1-2-1990, art. 4, § A)

Sec. 50-67. Duties and responsibilities of administrator.

Duties of the building official as the administrator of this chapter shall include, but not be limited to:

(1) Review of all development permits to assure that the permit requirements of this division have been satisfied.

(2) Advise permittee that additional federal or state permits may be required, and if specific federal or state permit requirements are known, require that copies of such permits be provided and maintained on file with the development permit.

(3) Notify adjacent communities and the state department of natural resources prior to any alteration or relocation of a watercourse, and submit evidence of such notification to the Federal Emergency Management Agency.

(4) Assure that maintenance is provided within the altered or relocated portion of such watercourse so that the flood-carrying capacity is not diminished.

(5) Verify and record the actual elevation, in relation to mean sea level, of the lowest floor, including basement, of all new or substantially improved buildings, in accordance with section 50-68(2).

(6) Verify and record the actual elevation, in relation to mean sea level, to which the new or substantially improved buildings have been floodproofed, in accordance with section 50-68(2).

(7) In coastal high hazard areas, certification shall be obtained from a registered professional engineer or architect that the building is designed and securely anchored to adequately anchored pilings or columns in order to withstand velocity waters and hurricane wave wash.

(8) In coastal high hazard areas, the building official shall review plans for adequacy of breakaway walls.

(9) When floodproofing is utilized for a particular building, the building official shall obtain certification from a registered professional engineer or architect in accordance with section 50-68(2).

(10) Where interpretation is needed as to the exact location of boundaries of the areas of special flood hazard, for example, where there appears to be a conflict between a mapped boundary and actual field conditions, the building official shall make the necessary interpretation. The person contesting the location of the boundary shall be given a reasonable opportunity to appeal the interpretation as provided in this division.

(11) When base flood elevation data or floodway data have not been provided in accordance with section 50-68, then the building official shall obtain, review and reasonably utilize any base flood elevation and floodway data available from a federal, state or other source, in order to administer the provisions of division 3 of this chapter.

(12) All records pertaining to the provisions of this chapter shall be maintained in the office of the building official and shall be open for public inspection.

(Ord. of 1-2-1990, art. 4, § C)

Sec. 50-68. Permit procedures.

Application for a development permit shall be made to the building official on forms furnished by him prior to any development activities, and may include, but shall not be limited to, the following plans, in duplicate, drawn to scale, showing the nature, location, dimensions and elevations of the area in question, existing or proposed structures, earthen fill, storage of materials or equipment, drainage facilities and their location. The following information is specifically required:

(1) Application stage.

a. Elevation in relation to mean sea level of the proposed lowest floor, including basement, of all buildings.

b. Elevation in relation to mean sea level to which any nonresidential building will be floodproofed.

c. Certificate from a registered professional engineer or architect that the nonresidential floodproofed building will meet the floodproofing criteria in section 50-92(9).

d. A description of the extent to which any watercourse will be altered or relocated as a result of the proposed development.

(2) Construction stage. Provide a floor elevation or floodproofing certification after the lowest floor is completed, or in instances where the building is subject to the regulations applicable to coastal high hazard areas, after placement of the horizontal structural members of the lowest floor. Upon placement of the lowest floor, or floodproofing by whatever construction means, or upon placement of the horizontal structural members of the lowest floor, whichever is applicable, it shall be the duty of the permit holder to submit to the building official a certification of the elevation of the lowest floor, floodproofed elevation or the elevation of the lowest portion of the horizontal structural members of the lowest floor, whichever is applicable, as-built, in relation to mean sea level. The certification shall be prepared by or under the direct supervision of a registered land surveyor or professional engineer and certified by him. When floodproofing is utilized for a particular building, the certification shall be prepared by or under the direct supervision of a professional engineer or architect and certified by him. Any work undertaken prior to submission of the certification shall be at the permit holder's risk. The building official shall review the floor elevation survey data submitted. Deficiencies detected by such review shall be corrected by the permit holder immediately and prior to further progressive work being permitted to proceed. Failure to submit the survey or failure to make such required corrections shall be cause to issue a stop work order for the project.

(Ord. of 1-2-1990, art. 4, § B)

Sec. 50-69. Variance.

(a) The aldermanic board as established by the city shall hear and decide appeals and requests for variances from the requirements of this chapter.

(b) The aldermanic board shall hear and decide appeals when it is alleged there is an error in any requirement, decision or determination made by the building official in the enforcement or administration of this chapter.

(c) Any person aggrieved by the decision of the aldermanic board or any taxpayer may appeal such decision to the superior court as provided by state law.

(d) Variances may be issued for 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 an historic structure and the variance is the minimum to preserve the historic character and design of the structure.

(e) In passing upon such applications, the aldermanic board shall consider all technical evaluations, all relevant factors, all standards specified in other sections of this chapter, and the:

(1) Danger that materials may be swept onto other lands to the injury of others;

(2) Danger to life and property due to flooding or erosion damage;

(3) Susceptibility of the proposed facility and its contents to flood damage and the effect of such damage on the individual owner;

(4) Importance of the services provided by the proposed facility to the city;

(5) Necessity of the facility to a waterfront location, in the case of a functionally dependent facility;

(6) Availability of alternative locations, not subject to flooding or erosion damage, for the proposed use;

(7) Compatibility of the proposed use with existing and anticipated development;

(8) Relationship of the proposed use to the comprehensive plan and floodplain management program for that area;

(9) Safety of access to the property in times of flood for ordinary and emergency vehicles;

(10) Expected heights, velocity, duration, rate of rise and sediment transport of the floodwaters and the effects of wave action, if applicable, expected at the site; and

(11) Costs of providing governmental services during and after flood conditions, including maintenance and repair of public utilities and facilities such as sewer, gas, electrical and water systems, and streets and bridges.

(f) Upon consideration of the factors listed in subsection (e) of this section, and the purposes of this chapter, the city council may attach such conditions to the granting of variances as it deems necessary to further the purposes of this chapter.

(g) Variances shall not be issued within any designated floodway if any increase in flood levels during the base flood discharge would result.

(h) Conditions for variances shall be as follows:

(1) Variances shall only be issued upon a determination that the variance is the minimum necessary, considering the flood hazard, to afford relief; and in the instance of an historical building, a determination that the variance is the minimum necessary so as not to destroy the historic character and design of the building.

(2) Variances shall only be issued upon a:

a. Showing of good and sufficient cause;

b. Determination that failure to grant the variance would result in exceptional hardship; and

c. Determination that the granting of a variance will not result in increased flood heights, additional threats to public safety, extraordinary public expense, create a nuisance, cause fraud on or victimization of the public, or conflict with existing local laws or ordinances.

(3) Any applicant to whom a variance is granted shall be given written notice specifying the difference between the base flood elevation and the elevation to which the building is to be built, and stating that the cost of flood insurance will be commensurate with the increased risk resulting from the reduced lowest floor elevation.

(4) The building official shall maintain the records of all appeal actions and report any variances to the Federal Emergency Management Agency, upon request.

(Ord. of 1-2-1990, art. 4, § D)

Secs. 50-70? 50-90. Reserved.

DIVISION 3.
FLOOD HAZARD REDUCTION

Sec. 50-91. Generally.

The following provisions are required in all areas of special flood hazard:

(1) New construction and substantial improvements shall be anchored to prevent flotation, collapse or lateral movement of the structure;

(2) Manufactured homes shall be anchored to prevent flotation, collapse or lateral movement. Methods of anchoring may include, but are not limited to, use of over-the-top or frame ties to ground anchors. This standard shall be in addition to and consistent with applicable state requirements for resisting wind forces;

(3) New construction and substantial improvements shall be constructed with materials and utility equipment resistant to flood damage;

(4) New construction or substantial improvements shall be constructed by methods and practices that minimize flood damage;

(5) Electrical, heating, ventilation, plumbing, and air conditioning equipment and other service facilities (including ductwork) must be elevated or waterproofed to the base flood elevation plus free board (one inch above BFE). To be fully compliant with the minimum requirements of the City of Pooler Flood Damage Prevention Ordinance, this equipment and service facilities (including ductwork) must be elevated or waterproofed to the base flood elevation plus free board (one inch above BFE).

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

(7) New and replacement sanitary sewer systems shall be designed to minimize or eliminate infiltration of floodwaters into the systems and discharges from the systems into floodwaters;

(8) On-site waste disposal systems shall be located and constructed to avoid impairment to them or contamination from them during flooding;

(9) Any alteration, repair, reconstruction or improvement to a building which is in compliance with the provisions of this chapter shall meet the requirements of new construction; and

(10) Any alteration, repair, reconstruction or improvement to a building which is not in compliance with the provisions of this chapter shall be undertaken only if such nonconformity is not furthered, extended or replaced.

(Ord. of 1-2-1990, art. 5, § A; Ord. of 7-12-2003, § II)

Sec. 50-92. Specific standards.

In all areas of special flood hazard where base flood elevation data has been provided as set forth in section 50-36 or section 50-67(11), the following provisions are required:

(1) Residential construction. New construction or substantial improvement of any residential building, or manufactured home, shall have the lowest floor, including basement, elevated no lower than one foot above the base flood elevation. Should solid foundation perimeter walls be used to elevate a structure, openings sufficient to facilitate the unimpeded movement of floodwaters shall be provided in accordance with standards set forth in subsection (3) of this section.

(2) Nonresidential construction. New construction or substantial improvement of any commercial, industrial or nonresidential building, or manufactured home, shall have the lowest floor, including basement, elevated no lower than one foot above the level of the base flood elevation. Buildings located in all A zones may be floodproofed in lieu of being elevated, provided that all areas of the building below the required elevation are watertight with walls substantially impermeable to the passage of water, and use structural components having the capability of resisting hydrostatic and hydrodynamic loads and the effect of buoyancy. A registered professional engineer or architect shall certify that the standards of this subsection are satisfied. Such certification shall be provided to the building official as set forth in section 50-67(9).

(3) Elevated buildings. New construction or substantial improvements of elevated 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.

a. 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.

b. Access to the enclosed area shall be the minimum necessary to allow for parking of vehicles (garage door) or limited storage of maintenance equipment used in connection with the premises (standard exterior door) or entry to the living area (stairway or elevator); and

c. The interior portion of such enclosed area shall not be partitioned or finished into separate rooms.

(4) Manufactured homes and recreational vehicles.

a. All manufactured homes placed or substantially improved on individual lots or parcels, in expansions to existing manufactured home parks or subdivisions, or in substantially improved manufactured home parks or subdivisions, must meet all of the requirements for new construction, including elevation and anchoring.

b. All manufactured homes placed or substantially improved in an existing manufactured home park or subdivision must be elevated so that:

1. The lowest floor of the manufactured home is elevated no lower than one foot above the level of the base flood elevation; or

2. The manufactured home chassis is supported by reinforced piers or other foundation elements of at least an equivalent strength of no less than 36 inches in height above grade;

3. The manufactured home must be securely anchored to the adequately anchored foundation system to resist flotation, collapse and lateral movement;

4. In an existing manufactured home park or subdivision on which a manufactured home has incurred substantial damage as the result of a flood, any manufactured home placed or substantially improved must meet the standards of subsection (4)b.1. and 3. of this section.

c. All recreational vehicles placed on sites must either:

1. Be fully licensed and ready for highway use; or

2. Must meet all the requirements for new construction, including anchoring and elevation requirements of subsection (4)a. or b. of this section.

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 structures.

(5) Floodways. Located within areas of special flood hazard established in section 50-36, are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of floodwaters which carry debris, potential projectiles and has erosion potential, the following provisions shall apply:

a. Encroachments, including fill, new construction, substantial improvements and other developments shall be prohibited unless certification, with supporting technical data, by a registered professional engineer is provided demonstrating that encroachments shall not result in any increase in flood levels during occurrence of the base flood discharge;

b. If the requirement of subsection (5)a. of this section is satisfied, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of this division;

c. Prohibit the placement of manufactured homes (mobile homes), except in an existing manufactured home (mobile home) park or subdivision. A replacement manufactured home may be placed on a lot in an existing manufactured home park or subdivision provided the anchoring standards of section 50-91(2), the elevation standards of subsection (1) of this section and the encroachment standards of subsection (5)a. of this section are met.

(Ord. of 1-2-1990, art. 5, § B)

Sec. 50-93. Streams without established base flood elevation and/or floodways.

Located within the areas of special flood hazard established in section 50-36 where streams exist but no base flood data have been provided (A-Zones), or where base flood data have been provided but a floodway has not been delineated, the following provisions apply:

(1) When base flood elevation data or floodway data have not been provided in accordance with section 50-36, then the building official shall obtain, review, and reasonably utilize any scientific or historic base flood elevation and floodway data available from a federal, state, or other source, in order to administer the provisions of article IV. Only if data is not available from these sources, the following subsections (2) and (3) shall apply:

(2) No encroachments, including structures or fill material, shall be located within an area equal to the width of the stream of 20 feet, whichever is greater, measured from the top of the stream bank, unless certification by a registered professional engineer is provided demonstrating that such encroachment shall not result in any increase in flood levels during the occurrence of the base flood discharge.

(3) In special flood hazard areas without base flood elevation data, new construction and substantial improvements of existing structures shall have the lowest floor of the lowest enclosed area (including basement) elevated no less than three feet above the highest adjacent grade at the building site. Openings sufficient to facilitate the unimpeded movements of flood waters shall be provided in accordance with standards of section 50-92(3), Elevated buildings.

The building official shall certify the lowest floor elevation level and the record shall become a permanent part of the permit file.

(Ord. of 1-2-1990, art. 5, § C; Ord. of 7-21-2003, § III)

Sec. 50-94. Subdivision proposals.

(a) All subdivision proposals shall be consistent with the need to minimize flood damage.

(b) All subdivision proposals shall have public utilities and facilities such as sewer, gas, electrical and water systems located and constructed to minimize flood damage.

(c) All subdivision proposals shall have adequate drainage provided to reduce exposure to flood hazards.

(d) Base flood elevation data shall be provided for subdivision proposals and other proposed development, including manufactured home parks and subdivisions, which is greater than the lesser of 50 lots or five acres.

(Ord. of 1-2-1990, art. 5, § D)

Sec. 50-95. Areas of shallow flooding (AO zones).

Located within the areas of special flood hazard established in section 50-36 are areas designated as shallow flooding areas. These areas have special flood hazards associated with base flood depths of one to three feet where a clearly defined channel does not exist and where the path of flooding is unpredictable and indeterminate, to which the following provisions apply:

(1) All new construction and substantial improvements of residential buildings shall have the lowest floor, including basement, elevated to the depth number specified on the flood insurance rate map, in feet, above the highest adjacent grade. If no depth number is specified, the lowest floor, including basement, shall be elevated at least two feet above the highest adjacent grade.

a. The lowest floor, including basement, shall be elevated to the depth number specified on the flood insurance rate map, in feet, above the highest adjacent grade. If no depth number is specified, the lowest floor, including basement, shall be elevated at least two feet above the highest adjacent grade; or

b. Together with attendant utility and sanitary facilities be completely floodproofed to or above that level so that any space below that level 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.

(Ord. of 1-2-1990, art. 5, § E)