Chapter 16.08
FLOOD DAMAGE PREVENTION
Sections:
Article I. Statutory Authorization, Findings of Fact, Purpose, and Objectives
16.08.010 Statutory authorization.
16.08.020 Findings of fact.
16.08.030 Statement of purpose.
16.08.040 Methods of reducing flood losses.
Article II. Definitions
16.08.050 Definitions.
Article III. General Provisions
16.08.060 Lands to which this chapter applies.
16.08.070 Basis for establishing the areas of special flood hazard.
16.08.080 Violations and penalties.
16.08.090 Abrogation and greater restrictions.
16.08.100 Interpretations.
16.08.110 Warning and disclaimer of liability.
Article IV. Administration
16.08.120 Development permit required.
16.08.130 Application for development permit.
16.08.140 Designation of the responsible official.
16.08.150 Duties and responsibilities of the building official.
Article V. Provisions for Flood Hazard Reduction
16.08.160 General standards.
16.08.170 Specific standards.
16.08.175 Recreational vehicles.
16.08.180 Repealed.
16.08.190 Wetlands management.
16.08.200 Encroachments.
16.08.210 Standards for shallow flooding areas (AO zones).
16.08.220 Coastal high hazard areas.
Article I. Statutory Authorization, Findings of Fact, Purpose, and Objectives
16.08.010 Statutory authorization.
The Legislature of the State of Washington has in Chapter 86-16 RCW, as amended, delegated the responsibility to local governmental units to adopt regulations designed to promote the public health, safety, and general welfare of its citizenry. (Ord. 2161 § 1.1, 1989).
16.08.020 Findings of fact.
A. The flood hazard areas of Port Townsend 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 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. (Ord. 2161 § 1.2, 1989).
16.08.030 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:
A. To protect human life and health;
B. To minimize expenditure of public money and costly flood control projects;
C. To minimize the need for rescue and relief efforts associated with flooding and generally undertaken at the expense of the general public;
D. To minimize prolonged business interruptions;
E. 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 flood hazard;
F. To help maintain a stable tax base by providing for the sound use and development of areas of special flood hazard so as to minimize future flood blight areas;
G. To ensure that potential buyers are notified that property is in an area of special flood hazard; and
H. To ensure that those who occupy the areas of special flood hazard assume responsibility for their actions. (Ord. 2161 § 1.3, 1989).
16.08.040 Methods of reducing flood losses.
In order to accomplish its purposes, this chapter includes methods and provisions for:
A. 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;
B. Requiring that uses vulnerable to floods, including facilities which serve such uses, be protected against flood damage at the time of initial construction;
C. Controlling the alteration of natural floodplains, stream channels, and natural protective barriers which help accommodate or channel floodwaters;
D. Controlling filling, grading, and other development which may increase flood damage; and
E. Preventing or regulating the construction of flood barriers which will unnaturally divert floodwaters or may increase flood hazards in other areas. (Ord. 2161 § 1.4, 1989).
Article II. Definitions
16.08.050 Definitions.
Unless specifically defined below, words or phrases used in this chapter shall be interpreted so as to give them the meaning they have in common usage and to give this chapter its most reasonable application.
A. “Appeal” means a request for review of the building department interpretation of any
provision of this chapter or a request for a variance.
B. “Area of shallow flooding” means a designated AO or AH 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. AO is characterized as sheet flow and AH indicates ponding.
C. “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. Designation on maps always includes the letter A or V.
D. “Breakaway wall” means a wall that is not a 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 supporting foundation system.
E. “Coastal high hazard area” means the area subject to high velocity waters, including but not limited to, storm surge or tsunamis. The area is designated on the FIRM as Zone V1-V30, VE or V.
F. “Critical facility” means a facility for which even a slight chance of flooding might be too great. Critical facilities include, but are not limited to schools, nursing homes, hospitals, police, fire and emergency response installations, installations which produce, use, or store hazardous materials or hazardous waste.
G. “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 located within the area of special flood hazard.
H. “Flood” or “flooding” means a general and temporary condition of partial or complete inundation of normally dry land areas from:
1. The overflow of inland or tidal waters; and/or
2. The unusual and rapid accumulation of runoff of surface waters from any source.
I. “Flood Insurance Rate Map (FIRM)” means the official map on which the Federal Insurance Administration has delineated both the areas of special flood hazards and the risk premium zones applicable to the community.
J. “Flood Insurance Study” means the official report provided by the Federal Insurance Administration that includes flood profiles, the Flood Boundary-Floodway Map, and the water surface elevation of the base flood.
K. “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.
L. “Lowest floor” means the lowest floor of the lowest enclosed area (including the basement). An unfinished or flood resistant enclosure, usable solely for parking of vehicles, building access or storage, in an area other than a basement area, is not considered a building’s lowest floor; provided, that such enclosure is not built so as to render the structure in violation of the applicable nonelevation design requirements of this chapter found at PTMC 16.08.170A.2.
M. “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 a site for greater than 180 consecutive days. For insurance purposes the term “manufactured home” does not include park trailers, travel trailers, and other similar vehicles.
N. “Manufactured home park or subdivision” means a parcel (or contiguous parcels) of land divided into two or more manufactured home lots for rent or sale.
O. “New construction” means structures for which the “start of construction” commenced on or after the effective date of the ordinance codified in this chapter.
P. “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 primarily not for use as a permanent dwelling but as temporary living quarters for recreational, camping, travel, or seasonal use.
Q. “Start of construction” includes substantial improvement, and means the date the building permit was issued, provided the actual start of construction, repair, reconstruction, placement or other improvement was within 180 days of the permit date. The actual start means either the first placement of permanent construction of a structure on a site, such as the pouring of slab or footings, the installation of piles, the 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 street and/or walkways; nor does it include excavation for a basement, footings, piers, or foundation 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 structure.
R. “Structure” means a walled or roofed building including a gas or liquid storage tank that is principally above ground.
S. “Substantial improvement” means any repair, reconstruction, or improvement of a structure, the cost of which equals or exceeds 50 percent of the market value of the structure either:
1. Before the improvement or repair is started; or
2. If the structure has been damaged and is being restored, before the damage occurred. For the purposes of this definition, “substantial improvement” is considered to occur when the first alteration of any wall, ceiling, floor, or other structural part of the building commences, whether or not that alteration affects the external dimensions of the structure.
The term does not, however, include either:
1. Any project for improvement of a structure to comply with existing state or local health, sanitary, or safety code specifications which are solely necessary to assure safe living conditions; or
2. Any alteration of a structure listed on the National Register of Historic Places or a State Inventory of Historic Places.
T. “Variances” means a grant of relief from the requirements of this chapter which permits construction in a manner that would otherwise be prohibited by this chapter.
U. “Water dependent” means a structure for commerce or industry which cannot exist in any other location and is dependent on the water by reason of the intrinsic nature of its operations. (Ord. 2854 § 5, 2004; Ord. 2161 § 2, 1989).
Article III. General Provisions
16.08.060 Lands to which this chapter applies.
This chapter shall apply to all areas of special flood hazards within the jurisdiction of the city of Port Townsend. (Ord. 2161 § 3.1, 1989).
16.08.070 Basis for establishing the areas of special flood hazard.
The areas of special flood hazard identified by the Federal Insurance Administration in a scientific and engineering report entitled “The Flood Insurance Study for the City of Port Townsend” dated September 15, 1981, with accompanying flood insurance maps and any revisions thereto is hereby adopted by reference and declared to be a part of this chapter. The Flood Insurance Study is on file with the city clerk at the office of the city administration. (Ord. 2854 § 1, 2004; Ord. 2161 § 3.2, 1989).
16.08.080 Violations and penalties.
A. Director’s Authority. Whenever the public works director or his or her designee (“director”) determines that a condition exists in violation of this chapter or any standard required to be adhered to by this chapter, or in violation of any permit issued hereunder, he or she is authorized to enforce the provisions of this chapter.
B. Chapter 1.20 PTMC Applicable. All violations of any provision of this chapter or incorporated standards, or of any permit issued hereunder, are made subject to the provisions of Chapter 1.20 PTMC. The director is authorized to order correction and discontinuance of any violative condition of the provisions of this chapter under the procedures of Chapter 1.20 PTMC, which provide for voluntary correction orders, formal notice and orders to correct the violation, abatement orders, stop work and emergency orders and assessment of civil penalties.
C. Order to Cease Violation. Whenever any such condition is found, pending commencement and completion of the voluntary correction and/or notice and order procedures of Chapter 1.20 PTMC, the director may order the cessation of activity causing the violative condition by notice in writing served on or mailed to the person(s) engaged in or causing such condition. The effect of such order shall be to require immediate cessation of any activity causing the violative condition. Such order shall not be affected by any right of appeal afforded by this or any other code provision.
D. Public Nuisance. All violations of this chapter and standards required thereby are determined to be detrimental to the public health, safety, and welfare and are public nuisances. All conditions which are determined by the director to be in violation of this chapter or standards required thereby shall be subject to the provisions of this chapter and shall be corrected by any reasonable and lawful means, as provided in Chapter 1.20 PTMC.
E. Alternative Remedies. As an alternative to any other judicial or administrative remedy provided in this chapter or by law or other ordinance, any person who willfully or knowingly violates or fails to comply with any stop work order or emergency order, issued pursuant to Chapter 1.20 PTMC is guilty of a misdemeanor and upon conviction shall be punished as provided in PTMC 1.20.060. Each day such violation or failure to comply continues shall be considered an additional misdemeanor offense. (Ord. 2952 § 1, 2008; Ord. 2510 § 1, 1996; Ord. 2161 § 3.3, 1989).
16.08.090 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. (Ord. 2161 § 3.4, 1989).
16.08.100 Interpretations.
In the interpretation and application of this chapter, all provisions shall be:
A. Considered as minimum requirements;
B. Liberally construed in favor of the governing body; and
C. Deemed neither to limit nor repeal any other powers granted under state statutes. (Ord. 2161 § 3.5, 1989).
16.08.110 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 considerations. 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 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 city of Port Townsend, 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 hereunder. (Ord. 2161 § 3.6, 1989).
Article IV. Administration
16.08.120 Development permit required.
A development permit shall be obtained before construction or development begins within any area of special flood hazard established in PTMC 16.08.070. The permit shall be for all structures including manufactured homes, as set forth in PTMC 16.08.050, and for all development including fill and other activities, also as set forth in PTMC 16.08.050. (Ord. 2161 § 4.1-1, 1989).
16.08.130 Application for development permit.
Application for a development permit shall be made on forms furnished by the building department and may include but not be 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:
A. Elevation in relation to mean sea level, of the lowest floor (including basement) of all structures;
B. Elevation in relation to mean sea level to which any structure has been floodproofed;
C. Certification by a registered professional engineer or architect that the floodproofing methods for any nonresidential structure meet the floodproofing criteria in PTMC 16.08.170B;
D. Description of the extent to which a watercourse will be altered or relocated as a result of proposed development. (Ord. 2161 § 4.1-2, 1989).
16.08.140 Designation of the responsible official.
The building official is designated to administer and implement this chapter by granting or denying development permit applications in accordance with its provisions. (Ord. 2161 § 4.2, 1989).
16.08.150 Duties and responsibilities of the building official.
Duties of the building official shall include, but not be limited to:
A. Permit Review.
1. Review all development permits to determine that the permit requirements of this chapter have been satisfied;
2. Review all development permits to determine that all necessary permits have been obtained from those federal, state, or local governmental agencies from which prior approval is required;
3. Review all development permits to determine if the proposed development is located in the floodway. If located in the floodway, assure that the provisions of PTMC 16.08.180 are met.
B. Use of Other Base Flood Data. When base flood elevation data has not been provided in accordance with PTMC 16.08.070, 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 PTMC 16.08.170 and 16.08.180.
C. Information to Be Obtained and Maintained.
1. Where base flood elevation data is provided through the Flood Insurance Study or required as in subsection B of this section, obtain and record the actual (as-built) elevation (in relation to mean sea level) of the lowest floor, including basement, of all new or substantially improved structures, and whether or not the structure contains a basement.
2. For all new or substantially improved floodproofed structures:
a. Verify and record the actual elevation (in relation to mean sea level) to which the structure was floodproofed; and
b. Maintain the floodproofing certifications required in PTMC 16.08.130(C).
3. Maintain for public inspection all records pertaining to the provisions of this chapter.
D. Alteration of Watercourses.
1. Notify adjacent communities and the Washington State Department of Ecology prior to any alteration or relocation of a watercourse, and submit evidence of such notification to the Federal Insurance Administration.
2. Require that maintenance is provided within the altered or relocated portion of said watercourse so that the flood-carrying capacity is not diminished.
E. Interpretation of FIRM Boundaries. Make interpretations where needed, as to exact location of the boundaries of the areas of special flood hazards (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. Such appeal shall be granted consistent with the standards of Section 60.6 of rules and regulations of the National Flood Insurance Program (44 CFR 59-76). (Ord. 2854 § 2, 2004; Ord. 2161 § 4.3, 1989).
Article V. Provisions for Flood Hazard Reduction
16.08.160 General standards.
In all areas of special flood hazards, the following standards are required.
A. Anchoring.
1. All new construction and substantial improvements shall be anchored to prevent flotation, collapse, or lateral movement of the structure.
2. All manufactured homes must likewise be anchored to prevent flotation, collapse or lateral movement, and shall be installed using methods and practices that minimize flood damage. Anchoring methods may include, but are not limited to, use of over-the-top or frame ties to ground anchors (Reference FEMA’s “Manufactured Home Installation in Flood Hazard Areas” guidebook for additional techniques).
B. Construction Materials and Methods.
1. All new construction and substantial improvement shall be constructed with materials and utility equipment resistant to flood damage.
2. All new construction and substantial improvements shall be constructed using methods and practices that minimize flood damage.
3. Electrical, heating, ventilation, plumbing, and air-conditioning equipment and other service facilities shall be designed and/or otherwise elevated or located so as to prevent water from entering or accumulating within the components during conditions of flooding.
C. Utilities.
1. All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of floodwaters into the system;
2. New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of floodwaters into the systems and discharge from the systems into floodwaters; and
3. On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.
D. Subdivision Proposals.
1. All subdivision proposals shall be consistent with the need to minimize flood damage;
2. All subdivision proposals shall have public utilities and facilities such as sewer, gas, electrical, and water systems located and constructed to minimize flood damage;
3. All subdivision proposals shall have adequate drainage provided to reduce exposure to flood damage; and
4. Where base flood elevation data has not been provided or is not available from another authoritative source, it shall be generated for subdivision proposals and other proposed developments which contain at least 50 lots or five acres (whichever is less).
E. Review of Building Permits. Where elevation data is not available either through the Flood Insurance Study or from another authoritative source (PTMC 16.08.150B), applications for building permits shall be reviewed to assure that proposed construction will be reasonably safe from flooding. The test of reasonableness is a local judgment and includes use of historical data, high water marks, photographs of past flooding, etc., where available. Failure to elevate at least two feet above grade in these zones may result in higher insurance rates. (Ord. 2161 § 5.1, 1989).
16.08.170 Specific standards.
In all areas of special flood hazards where base flood elevation data has been provided as set forth in PTMC 16.08.070 or 16.08.150(B), the following provisions are required:
A. Residential Construction.
1. New construction and substantial improvement of any residential structure shall have the lowest floor, including basement, elevated one foot or more above base flood elevation.
2. Fully enclosed areas below the lowest floor that are subject to flooding are prohibited, or shall be designed 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 must meet or exceed the following minimum criteria:
a. 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.
b. The bottom of all openings shall be no higher than one foot above grade.
c. Openings may be equipped with screens, louvers, or other coverings or devices provided that they permit the automatic entry and exit of floodwaters.
B. Nonresidential Construction. New construction and substantial improvement of any commercial, industrial or other nonresidential structure shall either have the lowest floor, including basement, elevated one foot or more above the level of the base flood elevation; or, together with attendant utility and sanitary facilities, shall:
1. Be floodproofed so that below one foot above 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;
3. Be certified by a registered professional engineer or architect that the design and methods of construction are in accordance with accepted standards of practice for meeting provisions of this subsection based on their development and/or review of the structural design, specifications and plans. Such certifications shall be provided to the official as set forth in PTMC 16.08.150(C)(2);
4. Nonresidential structures that are elevated, not floodproofed, must meet the same standards for space below the lowest floor as described in subsection (A)(2) of this section;
5. Applicants floodproofing nonresidential buildings shall be notified that flood insurance premiums will be based on rates that are one foot below the floodproofed level (e.g., a building floodproofed to one foot above the base flood level will be rated as at the base flood level).
C. Critical Facility. Construction of new critical facilities shall be, to the extent possible, located outside the limits of the base floodplain. Construction of new critical facilities shall be permissible within the base floodplain if no feasible alternative site is available. Critical facilities constructed within the base floodplain shall have the lowest floor elevated to three feet or more above the level of the base flood elevation at the site. Floodproofing and sealing measures must be taken to ensure that toxic substances will not be displaced by or released into floodwaters. Access routes elevated to or above the level of the base floodplain shall be provided to all critical facilities to the extent possible.
D. Manufactured Homes. All manufactured homes to be placed or substantially improved within the mapped 100-year floodplain on the community’s FIRM shall be elevated on a permanent foundation such that the lowest floor of the manufactured home is one foot or more above the base flood elevation; and be securely anchored to an adequately anchored foundation system in accordance with the provisions of PTMC 16.08.160(A)(2). (Ord. 2854 § 3, 2004; Ord. 2161 § 5.2, 1989).
16.08.175 Recreational vehicles.
Recreational vehicles placed on sites are required to either:
A. Be on the site for fewer than 180 consecutive days;
B. Be fully licensed and ready for highway use, on its wheels or jacking system, be attached to the site only by quick disconnect type utilities and security devices, and have no permanently attached additions; or
C. Meet the requirements of PTMC 16.08.170(D) pertaining to requirements for manufactured homes, including the elevation and anchoring requirements. (Ord. 2854 § 4, 2004).
16.08.180 Floodways.
Repealed by Ord. 2854. (Ord. 2161 § 5.3, 1989).
16.08.190 Wetlands management.
To the maximum extent possible avoid the short and long term adverse impacts associated with the destruction or modification of wetlands, especially those activities which limit or disrupt the ability of the wetland to alleviate flooding impacts. The following process should be implemented:
A. Review proposals for development within base floodplains for their possible impacts on wetlands located within the floodplain.
B. Ensure that development activities in or around wetlands do not negatively affect public safety, health, and welfare by disrupting the wetlands’ ability to reduce flood and storm drainage.
C. Request technical assistance from the Department of Ecology in identifying wetland areas. Existing wetland map information from the National Wetlands Inventory (NWI) can be used in conjunction with the community’s FIRM to prepare an overlay zone indicating critical wetland areas deserving special attention. (Ord. 2161 § 5.4, 1989).
16.08.200 Encroachments.
The cumulative effect of any proposed development, where 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. (Ord. 2161 § 5.5, 1989).
16.08.210 Standards for shallow flooding areas (AO zones).
Shallow flooding areas appear on FIRMs as AO Zones with depth designations. The base flood depths in these zones range from one to three feet above ground where a clearly defined channel does not exist, or where the path of flooding is unpredictable and where velocity flow may be evident. Such flooding is usually characterized as sheet flow. In these areas, the following provisions apply:
A. New construction and substantial improvements of residential structures within AO Zones shall have the lowest floor (including basement) elevated above the highest grade adjacent to the building, one foot or more above the depth number specified on the FIRM (at least two feet if no depth number is specified).
B. New construction and substantial improvements of nonresidential structures within AO Zones shall either:
1. Have the lowest floor (including basement) elevated above the highest adjacent grade of the building site, one foot or more above the depth number specified on the FIRM (at least two feet if no depth number is specified); or
2. 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. If this method is used, compliance shall be certified by a registered professional engineer or architect as in PTMC 16.08.170B.3.
C. Require adequate drainage paths around structures on slopes to guide floodwaters around and away from proposed structures. (Ord. 2161 § 5.6, 1989).
16.08.220 Coastal high hazard areas.
Located within areas of special flood hazard established in PTMC 16.08.070 are coastal high hazard areas, designated as Zones V1-V30, VE and/or V. These areas have special flood hazards associated with high velocity waters from surges and, therefore, in addition to meeting all provisions in this chapter, the following provisions shall also apply:
A. All new allowable construction and substantial improvements in Zones V1-V30 and VE (V if base flood elevation data is available) shall be elevated on pilings and columns so that:
1. The bottom of the lowest horizontal structural member of the lowest floor (excluding the pilings or columns) is elevated one foot or more above the base flood level; and
2. The pile or column foundation and structure attached thereto is anchored to resist flotation, collapse and lateral movement due to the effects of wind and water loads acting simultaneously on all building components. Wind and water loading values shall each have a one percent chance of being equaled or exceeded in any given year (100-year mean recurrence interval).
A registered professional engineer or architect shall develop or review the structural design, specifications and plans for the construction and shall certify that the design and methods of construction to be used are in accordance with accepted standards of practice for meeting the provisions of subdivisions (1) and (2) of this subsection.
B. Obtain the elevation (in relation to mean sea level), of the bottom of the lowest structural member of the lowest floor (excluding pilings and columns) of all new and substantially improved structures in Zones V1-V30 and VE, and whether or not such structures contain a basement. The local administrator shall maintain a record of all such information.
C. All new construction shall be located landward of the reach of mean high tide.
D. Provide that all new construction and substantial improvements 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 under wind and water loads without causing 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 safe loading resistance of not less than 10 and no more than 20 pounds per square foot. Use of breakaway walls which exceed a design safe 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 that which would occur during the base flood; and
2. The elevated portion of the building and supporting foundation system 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). Maximum wind and water loading values to be used in this determination shall each have a one percent chance of being equaled or exceeded in any given year (100-year mean recurrence interval).
E. If breakaway walls are utilized, such enclosed space shall be usable solely for parking of vehicles, building access, or storage. Such space shall not be used for human habitation.
F. Prohibit the use of fill for structural support of buildings.
G. Prohibit manmade alteration of sand dunes which would increase potential flood damage. (Ord. 2161 § 5.7, 1989).