Chapter 18.56 — FLOOD DAMAGE PREVENTION

The legislature of the state has delegated the responsibility to local governmental units to adopt regulations designated to promote the public health, safety and general welfare of its citizenry. Therefore, the council does ordain the provisions set out in this chapter.

(Code 1987, § 18.48.010; Ord. No. 38-1980, § 1.1, 1980)

Sec. 18.56.020. - Findings of fact.

• (a) The flood hazard areas of the town 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) These flood losses are caused by the cumulative effect of obstructions in the areas of special flood hazards which increase flood heights and velocities, and, when inadequately anchored, damage uses in other areas. Uses that are inadequately floodproofed, elevated or otherwise protected from flood damage also contribute to the flood loss.

(Code 1987, § 18.48.020; Ord. No. 38-1980, § 1.2, 1980)

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 designated:

• (1) To protect human life and health;

• (2) To minimize expenditure of public money for costly flood-control projects;

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

• (4) To minimize prolonged business interruptions;

• (5) To minimize damage to public facilities and utilities, such as water and gas mains, electric, telephone and sewer lines, streets, and bridges located in areas of special hazard;

• (6) To help maintain a stable tax base by providing for the second use and development of areas of special flood hazard so as to minimize future flood blight areas;

• (7) To ensure that potential buyers are notified that property is in an area of special flood hazard; and

• (8) To ensure that those who occupy the areas of special flood hazard assume responsibility for their actions.

(Code 1987, § 18.48.030; Ord. No. 38-1980, § 1.3, 1980)

Sec. 18.56.040. - Methods of reducing flood losses.

In order to accomplish its purposes, this chapter includes methods and provisions for the following:

• (1) Restricting or prohibiting 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) Requiring that uses vulnerable to floods, including facilities which serve such uses, be protected against flood damage at the time of initial construction;

• (3) Controlling the alteration of natural floodplains, stream channels, and natural protective barriers, which help accommodate or channel floodwaters;

• (4) Controlling filling, grading, dredging and other development which may increase flood damage; and

• (5) Preventing or regulating the construction of flood barriers which will unnaturally divert floodwaters, or which may increase flood hazards in other areas.

(Code 1987, § 18.48.040; Ord. No. 38-1980, § 1.4, 1980)

Sec. 18.56.050. - Interpretation of provisions.

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.

• (Code 1987, § 18.48.070; Ord. No. 38-1980, § 3.2, 1980)

Sec. 18.56.060. - 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 ordinance, easement, covenant or deed restriction conflict or overlap, whichever imposes the more stringent restrictions shall prevail.

(Code 1987, § 18.48.090; Ord. No. 38-1980, § 3.4, 1980)

Sec. 18.56.070. - Warning and disclaimer of liability.

• (a) The degree of flood protection required for this chapter is considered reasonable for regulatory purposes and is based on scientific and engineering considerations.

• (b) Larger floods can and will occur in rare occasions.

• (c) Flood heights may be increased by manmade or natural causes. This chapter does not imply that land outside the areas of special flood hazards, or uses permitted within such areas, will be free from flooding or flood damages. This chapter shall not create liability on the part of the town, any officer or employee thereof, or the Federal Insurance Administration, for any flood damages that result from reliance on this chapter or any administrative decision lawfully made thereunder.

(Code 1987, § 18.48.100; Ord. No. 38-1980, § 3.6, 1980)

Sec. 18.56.080. - 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:

Appeal means a request for a review of the town clerk's interpretation of any provision of this chapter.

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

Area of special flood hazard. See Special flood hazard area.

Area of special flood-related erosion hazard is the area subject to severe flood-related erosion losses; the area designated as Zone E on the flood insurance rate map (FIRM).

Area of special mudslide (i.e., mudflow) hazard is the area subject to severe mudslides (i.e., mudflows).The area is designated as Zone M on the flood insurance rate map (FIRM).

Base flood means the flood having one percent chance of being equaled or exceeded in any given year (also called the 100-year flood).

Basement means any area of the building having its floor subgrade (below ground level) on all sides.

Breakaway walls are any type of walls whether solid lattice, and whether constructed of concrete, masonry, wood, metal, plastic or any other suitable building material which is not part of the structural support of the building and which is designated to break away under abnormally high tides or wave action without causing any damage to the structural integrity of the building on which they are used or any building to which they might be carried by floodwaters. A breakaway wall shall have a safe design loading resistance of not less than ten and no more than 20 pounds per square foot. Use of breakaway walls must be certified by a registered engineer or architect and shall meet the following conditions:

• (1) Breakaway wall collapse shall result from a water load less than that which would occur during the base flood; and

• (2) The elevated portion of the building shall not incur any structural damage due to the effects of wind and water loads acting simultaneously in the event of the base flood.

Coastal high hazard areas is the area subject to high velocity waters, including coastal and tidal inundation or tsunamis. The area is designated on a flood insurance rate map (FIRM) as Zones V1-V30, 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, excavation or drilling operations.

Flood or flooding means a general and temporary condition or partial or complete inundation of normally dry land areas from the overflow of floodwaters, the unusual and rapid accumulation or runoff of surface waters from any source, and or the collapse of subsidence of land along the shore of a lake or other body of water as a result of erosion or undermining caused by waves or currents of water exceeding anticipated cyclical levels or suddenly caused by and unusually high water level in a natural body of water, accompanied by a severe storm, or by an unanticipated force of nature, such as flash flood or an abnormal tidal surge, or by some similarly unusual and unforeseeable event which result in flooding as defined in this definition.

Flood boundary and floodway map means the official map on which the Federal Emergency Management Agency or Federal Insurance Administration has delineated both the areas of flood hazard and the floodway.

Flood insurance rate map (FIRM) means the official map on which the Federal Emergency Management Agency or Federal Insurance Administration has delineated both the areas of special flood hazards and the risk premium zone applicable to the community.

Flood insurance study means the official report provided by the Federal Insurance Administration that includes flood profiles, the FIRM, the flood boundary and floodway map, and the water surface elevation of the base flood.

Floodplain or floodprone area means any land area susceptible to being inundated by water from any source. See Flooding.

Floodplain management means the operation of an overall program of corrective and preventive measures for reducing flood damage, including, but not limited to, emergency preparedness plans, flood control works and floodplain management regulations.

Floodplain management regulations means zoning ordinances, subdivision regulations, building codes, health regulations, special purpose ordinances (such as floodplain ordinance, grading ordinance and erosion control ordinance) and other applications of police power. The term "floodplain management regulations" describes such state or local regulations in any combination thereof, which provide standards for the purpose of flood damage prevention and reduction.

Floodproofing means any combination of structural and nonstructural additions, changes, or adjustments to structures which reduce or eliminate flood damage to real estate or improved real property, water and sanitary facilities, structures and their contents.

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. Also referred to as "regulatory floodway."

Functionally dependent use means a use which cannot perform its intended purpose unless it is located or carried out in close proximity to water. The term "functionally dependent use" includes only docking facilities, port facilities that are necessary for the loading and unloading of cargo or passengers, and ship building and ship repair facilities, but does not include long-term storage related manufacturing facilities.

Highest adjacent grade means the highest natural elevation of the ground surface prior to construction nearest to the proposed walls of a structure.

Lowest floor means 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 basement area is not considered a building's lowest floor, provided that such an enclosure is not built so as to render the structure in violation of the applicable non-elevation design requirements of this chapter.

Manufactured home means 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 connected to the required utilities. For floodplain management purposes, the term "manufactured home" also includes park trailers, travel trailers, and other similar vehicles placed on the site for greater than 180 consecutive days.

Manufactured home park or subdivision means a parcel or contiguous parcels of land divided into two or more manufactured home lots for sale or rent.

Mean sea level, for purposes of the National Flood Insurance Program, means the National Geodetic Vertical Datum (NGVD) of 1929 or other datum, to which base flood elevations shown on a community's flood insurance rate map are referenced.

New construction, for floodplain management purposes, means structures for which the start of construction commenced on or after the effective date of a floodplain management regulation adopted by this community.

100-year flood means a flood which has a one percent annual probability of being equaled or exceeded. It is identical to the "base flood," which will be the term used throughout this chapter.

Remedy a violation means to bring the structure or other development into compliance with state or local floodplain management regulations, or, if this is not possible, to reduce the impacts of its noncompliance. Ways that impacts may be reduced include protecting the structure or other affected development from flood damages, implementing the enforcement provisions of this article or otherwise deterring future similar violations, or reducing federal financial exposure with regard to the structure or other development.

t regulations, or, if this is not possible, to reduce the impacts of its noncompliance. Ways that impacts may be reduced include protecting the structure or other affected development from flood damages, implementing the enforcement provisions of this article or otherwise deterring future similar violations, or reducing federal financial exposure with regard to the structure or other development.

Special flood hazard area means an area having special flood, mudflow or flood-related erosion hazards and shown on a flood hazard boundary map (FHBM) or a flood insurance rate map (FIRM) Zone A, AO, A1-A30, AE, A99, AH, AR, AR/A, AR/AE, AR/AH, AR/AO, AR/A1-A30, V1-V30, VE or V. The SFHA is the area where the National Flood Insurance Program's (NFIP's) floodplain management regulations must be enforced and the area where the mandatory purchase of flood insurance applies.

Violation means the failure of a structure or other development to be fully compliant with the community's floodplain management regulations. A structure or other development without the elevation certificate, other certifications, or other evidence of compliance required in this chapter is presumed to be in violation until such time as that documentation is provided.

(Code 1987, §§ 18.48.290, 18.48.410)

Sec. 18.56.090. - Development permit; required; application information.

A development permit shall be obtained before construction or development begins within any area of special flood hazard defined in section 18.56.080. Application for a development permit shall be made on forms furnished by the county department of public works, and may include, but not limited to, plans in duplicate drawn to scale showing the nature, location, dimensions and elevations of the area in question; existing or proposed structures, fill, storage of materials, drainage facilities; and the location of the foregoing. Specifically, the following information is required:

• (1) Proposed elevation in relation to mean sea level, of the lowest floor (including basement) of all structures; in Zone AO or DO, elevation of highest adjacent grade and proposed elevation of the lowest floor of all structures;

• (2) Proposed elevation in relation to mean sea level to which any structure will be floodproofed;

• (3) All reports and certifications required by this chapter; and

• (4) Description of the extent to which any watercourse will be altered or relocated as a result of proposed development.

(Code 1987, § 18.48.420)

Sec. 18.56.100. - Designation of the floodplain administrator.

The county department of public works is appointed to administer and implement this chapter by granting or denying development permits in accordance with its provisions.

(Code 1987, § 18.48.430)

Sec. 18.56.110. - Duties and responsibilities of the floodplain administrator.

The duties and responsibilities of the floodplain administrator shall include, but not be limited to, the following:

• (1) Permit review.

  • a. Review all development permits to determine that the permit requirements of this chapter have been satisfied;

  • b. All other required state and federal permits have been obtained;

• c. The site is reasonably safe from flooding;

  • d. The proposed development does not adversely affect the carrying capacity. For purposes of this chapter, the term "adversely affects" means that the cumulative effect of the proposed development when combined with all other existing and anticipated development will not increase the water surface elevation of the base flood more than one foot at any point.

• (2) Use of other base flood data. When base flood elevation data has not been provided, the floodplain administrator 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 subsection (4) of this section. Any such information shall be submitted to the council for adoption.

• (3) When a watercourse is to be altered or relocated:

  • a. Notify adjacent communities and the state department of water resources prior to such alteration or relocation of a watercourse, and submit evidence of such notification to the Federal Insurance Administration;

  • b. Require that the flood carrying capacity of the altered or relocated portion of the watercourse is maintained.

• (4) Obtain and maintain for public inspection and make available as needed: a. The certifications required in sections: 1. 18.56.080 (definitions); 2. 18.56.200 (nonresidential construction); 3. 18.56.230 (standards of construction); 4. 18.56.250 (standards for subdivisions); and 5. 18.56.270 (floodways);

• b. The information required in section 18.56.280 (coastal high hazard areas); and

  • c. The report required in section 18.56.290(d)(4) (mudslide prone areas).

• (5) Make interpretations where needed, as to the exact location of the boundaries of the areas of special flood hazards, areas of flood-related erosion hazards or areas of mudslide (i.e., mudflow) (for example, where there appears to be a conflict between a mapped boundary and actual field conditions). The person contesting the location of the boundary shall be given a reasonable opportunity to appeal the interpretation as provided in article IV of this chapter.

• (6) Take action to remedy violations of this chapter as defined in section 18.56.080 as provided in section 1.04.110.

(Code 1987, § 18.48.440)

In all areas of special flood hazard, the standards set out in this article are required.

(Code 1987, § 18.48.340(2); Ord. No. 38-1980, § 5.1, 1980; Res. No. 992, app. A, § 18.48.340, 1-10-2011)

• (a) All new construction and substantial improvements shall be anchored to prevent flotation, collapse, or lateral movement of the structure.

• (b) All manufactured homes shall be anchored to resist flotation, collapse, or lateral movement by providing over-the-top and frame ties to ground anchors. Specific requirements shall be that:

  • (1) 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 manufactured homes less than 50 feet long requiring one additional tie per side;

  • (2) 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;

  • (3) All components of the anchoring system be capable of carrying a force of 4,800 pounds; and

  • (4) Any additions to the manufactured home be similarly anchored.

(Code 1987, § 18.48.350(2); Ord. No. 38-1980, § 5.1.1, 1980; Res. No. 992, app. A, § 18.48.350, 1-10-2011)

Sec. 18.56.140. - Construction materials and methods.

• (a) All new construction and substantial improvements shall be constructed with materials and utility equipment resistant to flood damage.

• (b) All new construction and substantial improvements shall be constructed using methods and practices that minimize flood damage.

(Code 1987, § 18.48.360; Ord. No. 38-1980, § 5.1.2, 1980; Res. No. 992, app. A, § 18.48.360, 1-10-2011)

Sec. 18.56.150. - Utilities.

• (a) All new and replacement water-supply systems shall be designated to minimize or eliminate infiltration of floodwaters into the system.

• (b) New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltrations of floodwaters into the system and discharge from the systems into floodwaters.

• (c) On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.

(Code 1987, § 18.48.370; Ord. No. 38-1980, § 5.1.3, 1980; Res. No. 992, app. A, § 18.48.370, 1-10-2011)

Sec. 18.56.160. - Subdivision proposal requirements.

• (a) All subdivision proposals shall:

  • (1) Be consistent with the need to minimize flood damage.

  • (2) Have public utilities and facilities, such as sewer, gas, electrical and water systems, located and constructed to minimize flood damage.

  • (3) Have adequate drainage provided to reduce exposure to flood damage.

• (b) Base flood elevation data shall be provided for subdivision proposals and other proposed developments which contain at least 50 lots or five acres, whichever is less.

(Code 1987, § 18.48.380; Ord. No. 38-1980, § 5.1.4, 1980; Res. No. 992, app. A, § 18.48.380, 1-10-2011)

The cumulative effect of any development, when combined with all other existing and anticipated development, shall not increase the water surface elevation of the base flood more than one foot at any point.

(Code 1987, § 18.48.390; Ord. No. 38-1980, § 5.1.5, 1980)

Sec. 18.56.180. - Specific standards designated.

In all areas of special flood hazard where base flood elevation data has been provided as set forth in section 18.56.160 or 18.56.310(b), the provisions set out in sections 18.56.210 through 18.56.230 are required.

(Code 1987, § 18.48.400; Ord. No. 38-1980, § 5.1, 1980)

Sec. 18.56.190. - Residential construction.

New construction and substantial improvement of any residential structure shall have the lowest floor, including basement, elevated to or above base flood elevation.

(Code 1987, § 18.48.410; Ord. No. 38-1980, § 5.2-1, 1980)

Sec. 18.56.200. - Nonresidential construction.

New construction and substantial improvement of any commercial, industrial or other nonresidential structure shall either have the lowest floor, including basement, elevated to the level of the base flood elevation, or, together with attendant utility and sanitary facilities, shall:

• (1) Be floodproofed so that below the base flood level the structure is watertight, with walls substantially impermeable to the passage of water;

• (2) Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy; and

• (3) Be certified by a registered professional engineer or architect that the standards of this subsection are satisfied. Such certifications shall be provided to the official as set forth in section 18.56.230(c)(3)c.

(Code 1987, § 18.48.420; Ord. No. 38-1980, § 5.2-2, 1980)

Sec. 18.56.210. - Manufactured homes.

• (a) Manufactured homes shall be anchored in accordance with section 18.56.130(b).

• (b) For new manufactured home parks and manufactured home subdivisions; for expansions to existing manufactured homes parks and manufactured home subdivisions; for existing manufactured home parks and manufactured home subdivisions where the repair, reconstruction or improvement of the streets, utilities and pads equals or exceeds 50 percent of the value of the streets, utilities and pads before repair, reconstruction or improvement has commenced; and for manufactured homes not placed in a manufactured home park or manufactured home subdivision, it is required that:

  • (1) Stands or lots are elevated on compacted fill or on pilings so that the lowest floor of the manufactured home will be at or above the base flood level;

  • (2) Adequate surface drainage and access for a hauler are provided; and

  • (3) In the instance of elevation on pilings, that:

    • a. Lots are large enough to permit steps;

    • b. Piling foundations are placed in stable soil no more than ten feet apart; and

    • c. Reinforcement is provided for piling more than six feet above the ground level.

(Code 1987, § 18.48.430; Ord. No. 38-1980, § 5.2-3, 1980)

Located within the areas of special flood hazard defined in section 18.56.080 are areas designated as shallow flooding. These areas have special flood hazards associated with base flood depths on one to three feet where a clearly defined channel does not exist and where the path of flooding is unpredictable and indeterminate. Therefore, the following provisions apply:

• (1) All new construction and substantial improvements of residential structures have the lowest floor, including the basement, elevated above the crown of the nearest street to or above the depth number specified in the communities FIRM.

• (2) All new construction and substantial improvements of nonresidential structures shall:

  • a. Have the lowest floor, including the basement, elevated above the crown of the nearest street to or above the depth number specified in the communities FIRM; or

  • b. Together with the 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.

(Code 1987, § 18.48.440; Ord. No. 38-1980, § 5.2-4, 1980)

Sec. 18.56.230. - Standards of construction.

In all areas of special flood hazards the following standards are required:

• (1) Anchoring.

  • a. 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.

  • b. All manufactured homes shall meet the anchoring standards of section 18.56.130(b).

• (2) Construction material.

  • a. All new construction and substantial improvements shall be constructed with materials and utility equipment resistant to flood damage.

  • b. All new construction and substantial improvements shall be constructed using methods and practices that minimize flood damage.

  • c. All new construction and substantial improvements shall be constructed with electrical, heating, ventilation, plumbing and air conditioning equipment and other service facilities that are designed or located so as to prevent water from entering or accumulating within the components during conditions of flooding.

  • d. Required within Zones AH, AO or VO, adequate drainage paths around structures on slopes to guide floodwaters around and away from proposed structures.

• (3) Elevation and floodproofing.

  • a. New construction and substantial improvement of any structure shall have the lowest floor, including basement, elevated to or above the base flood elevation. Nonresidential structures may meet the standards in section 18.56.200. Upon the completion of the structure the elevation of the lowest floor including basement shall be certified by a registered professional engineer or surveyor or verified by the community building inspector to be properly elevated. Such certification or verification shall be provided to the floodplain administrator.

elevation. Nonresidential structures may meet the standards in section 18.56.200. Upon the completion of the structure the elevation of the lowest floor including basement shall be certified by a registered professional engineer or surveyor or verified by the community building inspector to be properly elevated. Such certification or verification shall be provided to the floodplain administrator.

• b. New construction and substantial improvement of any structure in Zone AH, AO or VO shall have the lowest floor, including basement, elevated above the highest adjacent grade at least as high as the depth number specified in feet on the FIRM, or at least two feet if no depth number is specified. Nonresidential structures may meet the standards in section 18.56.200. Upon the completion of the structure the elevation of the lowest floor including basement shall be certified by a registered professional engineer or surveyor or verified by the community building inspector to be properly elevated. Such certification or verification shall be provided to the floodplain administrator.

• c. Nonresidential construction shall either be elevated in conformance with section 18.56.200 or together with attendant utility and sanitary facilities:

  1. Be floodproofed so that below the base flood level the structure is watertight with walls substantially impermeable to the passage of water;

  2. Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy; and

  3. Be certified by a registered professional engineer or architect that the standards of this subsection are satisfied. Such certifications shall be provided to the floodplain administrator.

• d. Require, for all new construction and substantial improvements, that fully enclosed areas below the lowest floor that are subject to flooding shall be designated to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of floodwaters. Designs for meeting this requirement must either be certified by a registered professional engineer or architect or meet or exceed the following minimum criteria:

  1. Either 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 shall be provided. The bottom of all openings shall be no higher than one-foot above grade. Openings may be equipped with screens, louvers, valves or other coverings or devices provided that they permit the automatic entry and exit of floodwaters; or

  2. Be certified to comply with a local floodproofing standard approved by the Federal Insurance Administration.

• e. Manufactured homes shall also meet the standards in section 18.56.130(b).

(Code 1987, § 18.48.450)

Sec. 18.56.240. - Standards for utilities.

• (a) All new and replacement water supply and sanitary sewage systems shall be designed to minimize or eliminate infiltration of floodwaters into the system and discharge from systems into floodwaters.

• (b) On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.

(Code 1987, § 18.48.460)

Sec. 18.56.250. - Standards for subdivisions.

• (a) All preliminary subdivision proposals shall identify the flood hazard area and the elevation of the base flood.

• (b) All final subdivision plans will provide the elevation of proposed structures and pads. If the site is filled above the base flood, the final pad elevation shall be certified by a registered professional engineer or surveyor and provided to the floodplain administrator.

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

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

• (e) All subdivisions shall be provide adequate drainage to reduce exposure to flood hazards.

(Code 1987, § 18.48.470)

Sec. 18.56.260. - Standards for manufactured homes.

All new and replacement manufactured homes and additions to manufactured homes shall:

• (1) Be elevated so that the lowest floor is at or above the base flood elevation; and

(2) Be securely anchored to a permanent foundation system to resist flotation, collapse or lateral movement.

(Code 1987, § 18.48.480)

Located within areas of special flood hazard defined in section 18.56.080 are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of floodwater which carry debris, potential projectiles, and erosion potential, the following provisions apply:

• (1) Prohibit encroachments, including fill, new construction, substantial improvements, and other development unless certification by a registered professional engineer or architect is provided demonstrating that encroachments shall not result in any increase in flood levels during the occurrence of the base flood discharge.

• (2) If subsection (1) of this section is satisfied, all new construction and substantial improvements shall comply with all other applicable flood hazard reduction provisions of this article.

(Code 1987, § 18.48.490)

Sec. 18.56.280. - Coastal high hazard areas.

Within costal high hazard areas defined in section 18.56.080, the following standards shall apply:

• (1) All new construction and substantial improvements shall be elevated on adequately anchored pilings or columns so that the lowest horizontal portion of the structural members of the lowest floor (excluding the pilings or columns) is elevated to or above the base flood elevation.

• (2) All new construction shall be located on the landward side of the reach of mean high tide.

• (3) All new construction and substantial improvements shall have the space below the lowest floor free of obstructions or constructed with breakaway walls. Such temporarily enclosed space shall not be used for human habitation.

• (4) Fill shall not be used for structural support of the building.

• (5) Manmade alteration of sand dunes which would increase potential flood damage is prohibited.

• (6) The floodplain administrator shall obtain and maintain the following records:

  • a. Certification by a registered engineer or architect that a proposed structure complies with section 18.56.270(1).

  • b. The elevation (in relation to mean sea level) of the bottom of the lowest structural member of the lowest floor (excluding pilings or columns) of all new and substantially improved structures contain a basement.

(Code 1987, § 18.48.500)

Sec. 18.56.290. - Mudslide prone areas.

• (a) The floodplain administrator shall review permits for proposed construction or other development to determine if it is within a mudslide area.

• (b) Permits shall be reviewed to determine that the proposed development is reasonably safe from mudslide hazards. Factors to be considered in making this determination include, but are not limited to, the following:

  • (1) The type and quality of soils;

  • (2) Evidence of groundwater or surface water problems;

  • (3) The depth and quality of any fill;

  • (4) The overall slope of the site; and

  • (5) The weight that any proposed development will impose on the slope.

• (c) Within areas which have mudslide hazards, the following requirements apply:

  • (1) A site investigation and further review shall be made by persons qualified in geology and soils engineering;

• (2) The proposed grading, excavation, new construction and substantial improvements shall be adequately designed and protected against mudslide damages;

  • (3) The proposed grading, excavation, new construction and substantial improvements do not aggravate the existing hazard by creating either on-site or off-site disturbances; and

  • (4) Drainage, planting, watering and maintenance shall not endanger slope stability.

• (d) Within Zone M on the flood insurance rate map, the town shall adopt a drainage ordinance which at least complies with the standards of the most recent edition of the Building Standards Code §§ 7001 through 7006 and 7008 through 7015:

  • (1) The location of foundation and utility systems of new construction and substantial improvements;

  • (2) The location, drainage and maintenance of all excavations, cuts and fills and planted slopes;

  • (3) Protective measures, including, but not limited to, retaining walls, buttress fills, sub drains, diverter terraces, benchings, etc.; and

  • (4)

Engineering drawings and specifications to be submitted for all corrective measures, accompanied by supporting soils engineering and geology reports. (Code 1987, § 18.48.510)

Sec. 18.56.300. - Flood-related erosion-prone areas.

• (a) The floodplain administrator shall require permits for proposed construction and other developments within all flood-related erosion-prone areas as known to the community.

• (b) Such permits shall be reviewed to determine whether the proposed site alterations and improvements will be reasonably safe from flood-related erosion and will not cause flood-related erosion hazards or otherwise aggravate the existing hazard.

• (c) If a proposed improvement is found to be in a path of flood-related erosion and would increase the erosion hazard, such improvement shall be relocated, or adequate protective measures shall be taken to avoid aggravating the existing erosion hazard.

• (d) Within Zone E on the flood insurance rate map, a setback is required for all new development from the ocean, lake, bay, riverfront or other body of water to create a safety buffer consisting of a natural vegetative or contour strip. This buffer shall be designated according to the flood-related erosion hazard and erosion rate, in relation to the anticipated useful life of the structures, and depending upon the geologic, hydrologic, topographic and climatic characteristics of the land. The buffer may be used for suitable open space purposes, such as for agricultural, forestry, outdoor recreation and wildlife habitat areas, and for other activities using temporary and portable structures only.

(Code 1987, § 18.48.520)

• (a) The town council shall hear and decide appeals and requests for variances from the requirements of this chapter.

• (b) The town council shall hear and decide appeals when it is alleged there is an error in any requirement, decision, or determination made by the floodplain administrator in the enforcement or administration of this chapter.

• (c) In passing upon such applications, the town council shall consider all technical evaluations, all relevant factors, standards specified in other sections of this chapter, and:

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

• (2) The danger of life and property due to flooding or erosion damage;

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

• (4) The importance of the services provided by the facility to the community;

• (5) The necessity to the facility of a waterfront location, where applicable;

• (6) The availability of alternative locations for the proposed use which are not subject to flooding or erosion damage;

• (7) The compatibility of the proposed use with existing and anticipated development;

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

• (9) The safety of access to the property in time of flood for ordinary and emergency vehicles;

• (10) The expected heights, velocity, duration, rate of rise, and sediment transport of the floodwaters expected at the site; and

• (11) The 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.

• (d) Generally, variances may be issued for new construction and substantial improvements to be erected on a lot of one-half acre or less in size contiguous to and surrounded by lots with existing structures constructed the base flood level, providing items listed in subsection (c)(1) through (c)(11) of this section have been fully considered. As the lot size increases beyond one half acre, the technical justification required for issuing the variance increases.

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

• (f) The floodplain administrator shall maintain the records of all appeal actions and report any variances to the Federal Insurance Administration upon request.

(Code 1987, § 18.48.530)

Sec. 18.56.320. - Conditions for variances.

• (a) Variances may be issued for the reconstruction, rehabilitation or restoration of structures listed in the National Register of Historic Places or the State Inventory of Historic Places, without regard to the procedures set forth in the remainder of this section.

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

• (c) Variances shall only be issued upon a determination that the variance is the minimum necessary, considering the flood hazard, to afford relief.

• (d) Variances shall only be issued upon:

  • (1) A showing of good and sufficient cause;

  • (2) A determination that failure to grant the variance would result in exceptional hardship to the applicant; and

  • (3) A determination that the granting of a variance will not result in increased flood heights, additional threats to public safety, extraordinary public expense, create nuisances, cause fraud on or victimization of, the public, or conflict with existing local laws or ordinances.

• (e) Variances may be issued for new construction and substantial improvements and for other development necessary for the conduct of a functionally dependent use provided that the provisions of this section are satisfied and that the structure or other development is protected by methods that minimize flood damages during base flood and create no additional threats to public safety.

• (f) Any applicant to whom a variance is granted shall be given written notice that the structure will be permitted to be built with the lowest floor elevation below the regulatory flood elevation and that the cost of flood insurance will be commensurate with the increased risk resulting from the reduced lowest floor elevation. A copy of the notice shall be recorded by the town council in the office of the county recorder and shall be recorded in a manner so that it appears in the chain of title of the affected parcel of land.

(Code 1987, § 18.48.540)