Chapter 15.16
DEVELOPMENT IN FLOOD AREAS
Sections:
15.16.010 Statutory authorization, findings of fact, purpose and objectives.
15.16.040 Lands to which chapter applies.
15.16.050 Basis for establishing areas of special flood hazard.
15.16.060 Local administrator.
15.16.080 General standards for flood hazard reduction.
15.16.090 Specific standards for flood hazard reduction.
15.16.100 Regulatory floodway not designated.
15.16.110 Areas designated as floodways.
15.16.120 Standards for shallow flooding areas (AO zones).
15.16.130 Coastal high hazard areas.
15.16.140 Construction of new critical facilities.
15.16.150 Interpretation of FIRM boundaries.
15.16.160 Conditions for variances.
15.16.170 Abrogation and greater restrictions.
15.16.180 Warning and disclaimer of liability.
15.16.190 Violations and penalties.
15.16.010 Statutory authorization, findings of fact, purpose and objectives.
A. 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. Protect human life and health.
2. Maximize benefit from expenditure of public money.
3. Minimize the need for rescue and relief efforts associated with flooding.
4. Avoid or minimize prolonged business interruptions.
5. Avoid or minimize damage to public facilities and infrastructure located in areas of special flood hazard.
6. Help maintain a stable tax base by providing for sound use and development of areas of special flood hazard so as to avoid or minimize future flood damage.
7. Ensure potential buyers are notified that property is in an area of special flood hazard.
8. Ensure those who occupy areas of special flood hazard assume responsibility for their actions.
B. Methods of Reducing Flood Losses. In order to accomplish its purposes, this chapter includes methods and provisions for:
1. Restricting or prohibiting uses that 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 that 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.
5. Preventing or regulating construction of flood barriers that could divert floodwaters from their natural course or may increase flood hazards in other areas. (Ord. 794 § 2 (part), 2012)
15.16.020 Definitions.
“Appeal” means a request for a review of the interpretation of any provision of this chapter or a request for a variance.
“Area of shallow flooding” means designated as an AO or AH zone on the Flood Insurance Rate Map (FIRM). AO zones have base flood depths that range from one (1) to three (3) feet above the natural ground, 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. AH indicates ponding, and is shown with standard base flood elevations.
“Area of special flood hazard” means the land in the floodplain within a community that is subject to a one percent (1%) or greater chance of flooding in any given year. Designation on maps always includes the letter A or V.
“Base flood” means the flood having a one percent (1%) chance of being equaled or exceeded in any given year (also referred to as the “one hundred (100) year flood”). It is designated on Flood Insurance Rate Maps (FIRM) by the letter A or V.
“Basement” means any area of the building having its floor sub-grade (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 supporting foundation system.
“Coastal high hazard area” means an area of special flood hazard extending from offshore to the inland limit of a primary frontal dune along an open coast and any other area subject to high velocity wave action from storms or seismic sources. The area is designated on the FIRM as zone V1-30, VE or V.
“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 and installations that produce, use or store hazardous materials or hazardous waste.
“Development or development activity” means any human-made change to improved or unimproved real estate, including but not limited to:
1. Construction, clearing, grading, filling, excavating, paving, dredging, mining, drilling or otherwise significantly disturbing the soil of a site.
2. Building, installing, enlarging, replacing or substantially restoring a structure, impervious surface or water management system.
3. Subdividing land into two (2) or more parcels.
4. Construction of a permanent sign, unless expressly exempted by this title.
5. Alteration of a historic property for which authorization is required by this title.
6. Changing the use of a site so that the need for parking is increased.
7. Storage of equipment or materials located within the area of special flood hazards.
“Development permit” means any written authorization from the city that authorizes the commencement of a development activity.
“Elevated building” means, for insurance purposes, a non-basement building that has its lowest elevated floor raised above ground level by foundation walls, shear walls, post, piers, pilings or columns.
“Elevation certificate” means the official form (FEMA Form 81-31) used to track development, provide elevation information necessary to ensure compliance with community floodplain management chapters, and determine the proper insurance premium rate with Section B completed by the city building inspector.
“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 adopted floodplain management regulations.
“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:
1. The overflow of inland or tidal waters.
2. The unusual and rapid accumulation of runoff of surface waters from any source.
“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.
“Flood Insurance Study (FIS)” means the official report provided by the Federal Insurance Administration that includes flood profiles, the Flood Insurance Rate Maps and the water surface elevation of the base flood.
“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 (1) foot.
“Lowest floor” means the lowest floor of the lowest enclosed area (including basements). 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 non-elevation design requirements of this chapter found at Section 15.16.090A2 (i.e., provided there are adequate flood ventilation openings).
“Manufactured home” means a structure, transportable in one (1) or more sections, which is built on a permanent chassis and is designed for use with or without a permanent foundation when attached to the required utilities. The term “manufactured home” does not include a “recreational vehicle.”
“Manufactured home park or subdivision” means a parcel (or contiguous parcels) of land divided into two (2) or more manufactured home lots for rent or sale.
“New construction” means structures for which the “start of construction” commenced on or after the effective date of this chapter.
“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 either final site grading or the pouring of concrete pads) is completed on or after the effective date of adopted floodplain management regulations.
“Recreational vehicle” means (1) a vehicle built on a single chassis; (2) four hundred (400) 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,” including substantial improvements, means the date the building permit was issued, provided the actual start of construction, repair, reconstruction, placement or other improvement was within one hundred eighty (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 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 structure. 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, including a gas or liquid storage tank, that is principally above ground.
“Substantial damage” means damage of any origin sustained by a structure whereby the cost of restoring the structure to its before damaged condition would equal or exceed fifty percent (50%) of the market value of the structure before the damage occurred.
“Substantial improvement” means any repair, reconstruction or improvement of a structure, the cost of which equals or exceeds fifty percent (50%) 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 can exclude: (1) any project for improvement of a structure to correct pre-cited existing violations of state or local health, sanitary or safety code specifications that have been previously identified by the local code enforcement official and which are the minimum 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.
“Variance” means a grant of relief from the requirements of this chapter that permits construction in a manner that would otherwise be prohibited by this chapter.
“Water dependent” means a structure for commerce or industry that cannot exist in any other location and is dependent on the water by reason of the intrinsic nature of its operations. (Ord. 816 § 1 (part), 2013; Ord. 794 § 2 (part), 2012)
15.16.030 Interpretation.
In the interpretation and application of this chapter, all provisions shall be:
A. Considered as minimum requirements.
B. Deemed neither to limit nor repeal any other powers granted under state statutes. (Ord. 794 § 2 (part), 2012)
15.16.040 Lands to which chapter applies.
This chapter shall apply to all areas of special flood hazard within the jurisdiction of the city. (Ord. 794 § 2 (part), 2012)
15.16.050 Basis for establishing 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 (FIS) for Pacific County and Incorporated Areas” effective May 18, 2015, and any revisions thereto, with accompanying Flood Insurance Rate Maps (FIRMs), and any revisions thereto, are hereby adopted by reference and declared to be a part of this chapter. The FIRM is on file at Ilwaco City Hall, 120 First Ave. N., Ilwaco, WA. The best available information for flood hazard area identification as outlined in Section 15.16.060B2 shall be the basis for regulation until a new FIRM is issued that incorporates the data utilized under Section 15.16.060B2. (Ord. 843 § 1, 2015; Ord. 816 § 1 (part), 2013; Ord. 794 § 2 (part), 2012)
15.16.060 Local administrator.
A. Appointment. The mayor or mayor’s designee is hereby appointed to administer and implement this chapter by granting or denying development permit applications in accordance with its provisions.
B. Duties and Responsibilities. Duties of the local administrator shall include, but not be limited to:
1. Permit Threshold Review. Review all development permits to determine if the proposed development falls within areas covered by this chapter. If not, the review is complete. If so, conduct further permit review for developments in defined flood areas as follows:
a. Confirm that permit requirements of this chapter have been satisfied.
b. Review 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.
c. Review development permits to determine if proposed development is located in the floodway. If located in the floodway, ensure that encroachment provisions of Section 15.16.110A are met.
2. Use of Other Base Flood Data (in A and V Zones). When base flood elevation data have not been provided (A and V zones) in accordance with Section 15.16.050, the local 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 Sections 15.16.100 and 15.16.120.
3. Information to Be Obtained and Maintained.
a. Where base flood elevation data is provided through the Flood Insurance Study, FIRM or required as in subsection B2 of this section, obtain and record the actual 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.
b. For all new or substantially improved floodproofed structures where base flood elevation data is provided through the flood insurance study, FIRM or as required in subsection B2 of this section:
i. Obtain and record the elevation (in relation to mean sea level) to which the structure was floodproofed.
ii. Maintain the floodproofing certifications required in Section 15.16.070B3.
c. Maintain for public inspection all records pertaining to provisions of this chapter.
C. Alteration of Watercourses.
1. Notify adjacent communities and the 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.
D. Interpretation of FIRM Boundaries. Make interpretations where needed, as to exact location of the 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 person contesting the location of the boundary shall be given a reasonable opportunity to appeal the interpretation as provided in Section 15.16.150. (Ord. 816 § 1 (part), 2013; Ord. 794 § 2 (part), 2012)
15.16.070 Development permit.
A. Permit Required. A development permit shall be obtained before construction or development begins within any area of special flood hazard established in Section 15.16.050. The permit shall be for all structures including “manufactured homes,” as set forth in Section 15.16.020, and for all “development,” including fill and other activities, also as set forth in the definitions, Section 15.16.020.
B. Application for Development Permit. Application for a development permit shall be made on forms furnished by the city and shall include and 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, fill, storage of materials and drainage facilities. Specifically, the following information is required:
1. Elevation in relation to mean sea level, of the lowest floor (including basement) of all structures.
2. Elevation to which any structure has been floodproofed relative to mean sea level.
3. Certification by a registered professional engineer or architect that floodproofing methods for any nonresidential structure meet floodproofing criteria in Section 15.16.090.
4. Description of the extent to which a watercourse will be altered or relocated as a result of proposed development. (Ord. 794 § 2 (part), 2012)
15.16.080 General standards for flood hazard reduction.
In all areas of special flood hazard, 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. AH Zone Drainage. Adequate drainage paths are required around structures on slopes to guide floodwaters around and away from proposed structures.
C. Construction Materials and Methods.
1. All new construction and substantial improvements 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.
D. Utilities.
1. All new and replacement water supply systems shall be designed to avoid or minimize infiltration of floodwaters into the systems.
2. Any proposed water well shall be located on high ground that is not in the floodway (WAC 173-160-171).
3. New and replacement sanitary sewage systems shall be designed to avoid or minimize infiltration of floodwaters into the systems and discharges from the systems into floodwaters.
4. On-site waste disposal systems shall be located to avoid impairment of them or contamination from them during flooding.
E. 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 or eliminate flood damage.
3. All subdivision proposals shall have adequate drainage provided to reduce exposure to flood damage.
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 fifty (50) lots or five (5) acres (whichever is less).
F. Review of Building Permits. Where elevation data are not available either through the flood insurance study, FIRM or from another authoritative source (Section 15.16.050), 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 (2) feet above the highest adjacent grade in these zones may result in higher insurance rates. (Ord. 794 § 2 (part), 2012)
15.16.090 Specific standards for flood hazard reduction.
In all areas of special flood hazard where base flood elevation data have been provided as set forth in Section 15.16.050, 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 a minimum of one (1) foot above the 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 and below-grade crawlspaces will not be considered basements if the following conditions are met:
a. The interior grade of a crawlspace below the BFE must not be more than two (2) feet below the lowest adjacent exterior grade.
b. The height of the below-grade crawlspace, measured from the interior grade of the crawlspace to the top of the floor joist, must not exceed four (4) feet at any point.
c. There must be an adequate drainage system that removes floodwaters from the interior of the crawlspace. The enclosed area should be drained within a reasonable time after a flood event.
d. The velocity of floodwater at the site should not exceed five (5) feet per second.
e. Ductwork must either be placed above the BFE or sealed to prevent the entry of floodwaters.
f. Buildings that have below-grade crawlspaces will have higher flood insurance premiums than buildings that have the interior elevation at or above the lowest adjacent exterior grade. For additional information, refer to FEMA Technical Bulletin 11.
3. Or must meet or exceed the following minimum criteria:
a. A minimum of two (2) openings having a total net area of not less than one (1) square inch for every square foot of enclosed area subject to flooding shall be provided on different sides of each enclosed area.
b. The bottom of all openings shall be a maximum of one (1) foot above grade.
c. Openings may be equipped with screens, louvers or other coverings or devices provided such openings allow automatic entry and exit of floodwaters.
d. The interior grade of a crawlspace below the base flood elevation shall not be more than two (2) feet below the lowest adjacent exterior grade.
e. The height of a below-grade crawl space, measured from the interior grade of the crawlspace to the top of the crawlspace foundation wall shall not exceed four (4) feet at any point.
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 a minimum of one (1) foot above the base flood elevation; or, together with attendant utility and sanitary facilities, shall:
1. Be floodproofed so that beneath one (1) foot above 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 proposed design and methods of construction are in accordance with accepted standards of practice for meeting provisions of this subsection, based on the engineer’s or architect’s development and/or review of the structural design, specifications and plans. Such certifications shall be provided to the official as set forth in Section 15.16.060B3b.
4. Nonresidential structures that are elevated, not floodproofed, must meet the same standards for space below the lowest floor as described in subsection A2 of this section.
5. Applicants floodproofing nonresidential buildings shall be notified that flood insurance premiums will be based on rates that are one (1) foot below the floodproofed level (e.g., a building floodproofed to the base flood level will be rated as one (1) foot below).
6. Any below-grade crawlspace must comply with subsections A2d and e of this section.
C. Manufactured Homes.
1. All manufactured homes to be placed or substantially improved on sites outside of a manufactured home park or subdivision, in a new manufactured home park or subdivision, in an expansion to an existing manufactured home park or subdivision or in an existing manufactured home park or subdivision on which a manufactured home has incurred “substantial damage” as the result of a flood shall be elevated on a permanent foundation such that the lowest floor of the manufactured home is elevated a minimum of one (1) foot above the base flood elevation and be securely anchored to an adequately designed foundation system to resist flotation, collapse and lateral movement.
2. Manufactured homes to be placed or substantially improved on sites in an existing manufactured home park or subdivision that are not subject to the above manufactured home provisions shall be elevated so that either:
a. The lowest floor of the manufactured home is elevated a minimum of one (1) foot above the base flood elevation.
b. The manufactured home chassis is supported by reinforced piers or other foundation elements of at least equivalent strength that are no less than thirty-six (36) inches in height above grade and are securely anchored to an adequately designed foundation system to resist flotation, collapse and lateral movement.
3. Any below-grade crawlspace must comply with subsections A2d and e of this section.
D. Recreational Vehicles. Recreational vehicles placed on sites are required to either:
1. Be on the site for fewer than one hundred eighty (180) consecutive days, and 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.
2. Meet the requirements of subsection C of this section and the elevation and anchoring requirements for manufactured homes per Section 15.16.080A2. (Ord. 847 § 1, 2015; Ord. 816 § 1 (part), 2013; Ord. 794 § 2 (part), 2012)
15.16.100 Regulatory floodway not designated.
In areas where a regulatory floodway has not been designated, no new construction, substantial improvements or other development (including fill) shall be permitted within zones A1-30 and AE on the community’s FIRM, unless it is demonstrated 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 (1) foot at any point within the community. (Ord. 794 § 2 (part), 2012)
15.16.110 Areas designated as floodways.
Located within areas of special flood hazard established in Section 15.16.050 are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of floodwaters, which carry debris and potential projectiles, and which have erosion potential, the following provisions apply:
A. Encroachments Prohibited. Encroachments, including fill, new construction, substantial improvements and other development are prohibited unless certification by a registered professional engineer is provided demonstrating through hydrologic and hydraulic analyses performed in accordance with standard engineering practice that a proposed encroachment would not result in any increase in flood levels during the base flood discharge.
B. Construction or Reconstruction Prohibited. Construction or reconstruction of residential structures is prohibited within designated floodways, except for: (1) repairs, reconstruction or improvements to a structure which do not increase the ground floor area; and (2) repairs, reconstruction or improvements to a structure, the cost of which does not exceed fifty percent (50%) of the market value of the structure either (a) before the repair or reconstruction is started, or (b) if the structure has been damaged, and is being restored, before the damage occurred. Any project for improvement of a structure to correct existing violations of state or local health, sanitary or safety code specifications which have been identified by the local code enforcement official and which are the minimum necessary to assure safe living conditions or to structures identified as historic places shall not be included in the fifty percent (50%).
C. Compliance with Certain Provisions. If subsection A of this section is satisfied, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of Sections 15.16.080 through 15.16.140. (Ord. 794 § 2 (part), 2012)
15.16.120 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 (1) to three (3) 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. Residential Structures and Manufactured Homes. New construction and substantial improvements of residential structures and manufactured homes within AO zones shall have the lowest floor (including basement) elevated above the highest adjacent grade to the structure a minimum of one (1) foot above the depth number specified in feet on the community’s FIRM (at least two (2) feet above the highest adjacent grade to the structure if no depth number is specified).
B. Nonresidential Structures. 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 a minimum of one (1) foot or more above the depth number specified on the FIRM (at least two (2) feet if no depth number is specified).
2. Together with attendant utility and sanitary facilities, be completely floodproofed to or above the FIRM depth 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 Section 15.16.090B3.
C. Drainage. Adequate drainage paths shall be placed around structures on slopes to guide floodwaters around and away from proposed structures.
D. Recreational Vehicles. Recreational vehicles placed on sites within AO zones on the community’s FIRM are required to either:
1. Be on the site for fewer than one hundred eighty (180) consecutive days, and 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.
2. Meet the requirements of subsections A and C of this section and the anchoring requirements for manufactured homes (Section 15.16.080A2). (Ord. 794 § 2 (part), 2012)
15.16.130 Coastal high hazard areas.
Located within areas of special flood hazard established in Section 15.16.050 are coastal high hazard areas, designated as zones V1-30, 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. Design and Method of Construction.
1. All new construction and substantial improvements in zones V1-30 and VE (V if base flood elevation data is available) on the community’s FIRM shall be elevated on pilings and columns so that:
a. The bottom of the lowest horizontal structural member of the lowest floor (excluding the pilings or columns) is elevated a minimum of one (1) foot above the base flood level; and
b. The pile or column foundation and structure attached thereto is anchored to resist flotation, collapse and lateral movement resulting from wind and water loads acting simultaneously on all building components. Wind and water loading values shall each have a one percent (1%) chance of being equaled or exceeded in any given year (a one (1) in one hundred (100) chance, based on the one hundred (100) year mean recurrence interval as defined in Section 15.16.020, Definitions).
2. A registered professional engineer or architect shall develop or review the structural design, specifications and plans for construction, and shall certify the design and methods of construction to be used are in accordance with accepted standards of practice for meeting provisions of subsection A1 of this section.
B. Record of Elevation. 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 each new and substantially improved structure in zones V1-30, VE and V on the community’s FIRM, and ascertain whether or not each structure contains a basement. The local administrator shall maintain a record of all such information.
C. Location. All new construction within zones V1-30, VE and V on the community’s FIRM shall be located landward of the reach of mean high tide.
D. Breakaway Walls.
1. All new construction and substantial improvements within zones V1-30, VE and V on the community’s FIRM shall have the space below the lowest floor either free of obstructions or constructed with non-supporting 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 purposes of this section, a breakaway wall shall have a design safe loading resistance of not less than ten (10) and no more than twenty (20) pounds per square foot. Use of breakaway walls which exceed a design safe loading resistance of twenty (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 the design as proposed meets the following conditions:
a. Breakaway wall collapse shall result from water load less than that which would occur during the base flood.
b. 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 (1%) chance of being equaled or exceeded in any given year (a one (1) in one hundred (100) chance, based on the one hundred (100) year mean recurrence interval as defined in Section 15.16.020, Definitions).
2. If breakaway walls are utilized space enclosed or partially enclosed by such walls shall be useable solely for parking of vehicles, building access or storage. Such space shall not be used for human habitation.
E. Fill Prohibited. Use of fill for structural support of buildings within zones V1-30, VE and V on the community’s FIRM shall be prohibited.
F. Alteration of Sand Dunes Prohibited. Human-made alteration of sand dunes within zones V1-30, VE and V on the community’s FIRM that would increase potential flood damage shall be prohibited.
G. Manufactured Homes. All manufactured homes to be placed or substantially improved within zones V1-30, V and VE on the community’s FIRM on sites located outside of a manufactured home park or subdivision, in a new manufactured home park or subdivision, in an expansion to an existing manufactured home park or subdivision or in an existing manufactured home park or subdivision on which a manufactured home has incurred “substantial damage” as the result of a flood shall meet standards of subsections A through F of this section. Manufactured homes placed or substantially improved on other sites in an existing manufactured home park or subdivision within zones V1-30, V and VE on the FIRM shall meet requirements of Chapter 15.84.
H. Recreational Vehicles. RVs placed on sites within zones V1-30, V and VE on the community’s FIRM are required to either:
1. Be on the site for fewer than one hundred eighty (180) consecutive days, and 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.
2. Meet the requirements of Section 15.16.080A2, and subsections A through F of this section. (Ord. 794 § 2 (part), 2012)
15.16.140 Construction of new critical facilities.
A. Location. Construction of new critical facilities shall be, to the extent feasible, located outside the limits of the special flood hazard area (SFHA) (one hundred (100) year floodplain).
B. Site. Construction of new critical facilities shall be permissible within the SFHA if no feasible alternative site is available.
C. Lowest Floor Elevation. Critical facilities constructed within the SFHA shall have the lowest floor elevated a minimum three (3) feet above the base flood level or to the height of the five hundred (500) year flood, whichever is higher. Access to and from the critical facility should also be protected to the height utilized above.
D. Floodproofing and Sealing. Floodproofing and sealing measures must be taken to ensure that toxic substances will not be displaced by or released into floodwaters.
E. Access Routes. Access routes elevated to or above the level of the base flood elevation shall be provided to all critical facilities to the extent possible. (Ord. 794 § 2 (part), 2012)
15.16.150 Interpretation of FIRM boundaries.
Make interpretations where needed, as to exact location of the boundaries of the areas of special flood hazards (e.g., 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 appeals shall be granted consistent with the standards of Section 60.6 of the Rules and Regulations of the National Flood Insurance Program. (Ord. 794 § 2 (part), 2012)
15.16.160 Conditions for variances.
A. Generally, the only condition under which a variance from the elevation standard may be issued is for new construction and substantial improvements to be erected on a small or irregularly shaped lot contiguous to and surrounded by lots with existing structures constructed below the base flood level. As the lot size increases, the technical justification required for issuing the variance increases.
B. Variances shall not be issued within a 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.
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 as interpreted in the National Flood Insurance Program are based on the general zoning law principle that they pertain to a physical piece of property; they are not personal in nature and do not pertain to the structure, its inhabitants, economic or financial circumstances. They primarily address small lots in densely populated residential neighborhoods. As such, variances from flood elevations should be quite rare.
F. Variances may be issued for nonresidential buildings in very limited circumstances to allow a lesser degree of floodproofing than watertight or dry-floodproofing, where it can be determined that such action will have low damage potential, complies with all other variance criteria except subsection D1 of this section, and otherwise complies with Sections 15.16.080A, D and E of the general standards.
G. Any applicant to whom a variance is granted shall be given written notice that the permitted structure will be built with its lowest floor below the base flood elevation and that the cost of flood insurance will be commensurate with the increased risk. (Ord. 794 § 2 (part), 2012)
15.16.170 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. 794 § 2 (part), 2012)
15.16.180 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 hazard 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, 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. 794 § 2 (part), 2012)
15.16.190 Violations and penalties.
Penalties for violations of this chapter shall be assessed and enforced pursuant to Section 15.02.140, Violations and penalties. (Ord. 794 § 2 (part), 2012)