Chapter 23.40
FLOOD CONTROL1
Sections:
23.40.010 Statutory authorization.
23.40.030 Statement of purpose.
23.40.040 Methods of reducing flood losses.
23.40.060 Lands to which this chapter applies.
23.40.070 Basis for establishing the areas of special flood hazard.
23.40.080 Penalties for noncompliance.
23.40.090 Abrogation and greater restrictions.
23.40.110 Warning and disclaimer of liability.
23.40.115 Establishment of development permit.
23.40.117 Designation of the floodplain administrator.
23.40.120 Duties and responsibilities of the community development manager.
23.40.130 Provisions for flood hazard reduction.
23.40.170 Standards for shallow flooding areas (AO zones).
23.40.010 Statutory authorization.
The legislature of the state of Washington has delegated the responsibility to local governmental units to adopt floodplain management regulations designed to promote the public health, safety, and general welfare of its citizenry. (Ord. 2031 § 1 (Exh. A), 2020; Ord. 2018 § 3 (Exh. A), 2020; Ord. 1639 § 1, 2006).
23.40.020 Findings of fact.
A. The flood hazard areas of the city are subject to periodic inundation which results in loss of life and property, health and safety hazards, disruption of commerce and governmental services, extraordinary public expenditures for flood protection and relief, and impairment of the tax base, all of which adversely affect the public health, safety, and general welfare.
B. These flood losses may be caused by the cumulative effect of obstructions in flood hazard areas 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. 2031 § 1 (Exh. A), 2020; Ord. 2018 § 3 (Exh. A), 2020; Ord. 1639 § 1, 2006).
23.40.030 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 flooding in flood hazard 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 flood hazard areas so as to minimize future flood blight areas;
G. To notify potential buyers that the property is in a special flood hazard area;
H. To notify those who occupy flood hazard areas that they assume responsibility for their actions; and
I. To participate in and maintain eligibility for flood insurance and disaster relief. (Ord. 2031 § 1 (Exh. A), 2020; Ord. 2018 § 3 (Exh. A), 2020; Ord. 1639 § 1, 2006).
23.40.040 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 flood waters;
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 flood waters or may increase flood hazards in other areas. (Ord. 2031 § 1 (Exh. A), 2020; Ord. 2018 § 3 (Exh. A), 2020; Ord. 1639 § 1, 2006).
23.40.050 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 a review of the floodplain administrator’s interpretation of any provision of this chapter or a request for a variance.
B. “Area of shallow flooding” means a designated AO, AH, AR/AO or AR/AH (or VO) zone on the flood insurance rate map (FIRM) with a one percent or greater annual chance of flooding to an average depth of one to three feet where a clearly defined channel does not exist, where the path of flooding is unpredictable, and where velocity flow may be evident. Such flooding is characterized by ponding or sheet flow.
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. It is shown on the flood insurance rate map (FIRM) as Zone A, AO, AH, A1-30, AE, A99, AR (V, VO, V1-30, VE). “Special flood hazard area” is synonymous in meaning with the phrase “area of special flood hazard.”
D. “Base flood” means the flood having a one percent chance of being equaled or exceeded in any given year. “Base flood” is also referred to as the “100-year flood.” Designation on maps always includes the letter A or V.
E. “Basement” means any area of the building having its floor subgrade (below ground level) on all sides.
F. “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.
G. Building. See “Structure.”
H. “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 which produce, use, or store hazardous materials or hazardous waste.
I. “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 or storage of equipment or materials.
J. “Elevated building” means, for insurance purposes, a nonbasement building which has its lowest elevated floor raised above ground level by foundation walls, shear walls, posts, piers, pilings or columns.
K. “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 pouring of concrete pads) is completed before the effective date of the adopted floodplain management regulations.
L. “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 grading or the pouring of concrete pads).
M. Flood or Flooding.
1. A general and temporary condition of partial or complete inundation of normally dry land areas from:
a. The overflow of inland or tidal waters.
b. The unusual and rapid accumulation or runoff of surface waters from any source.
c. Mudslides (i.e., mudflows) which are proximately caused by flooding as defined in subsection (1)(b) of this definition and are akin to a river of liquid and flowing mud on the surfaces of normally dry land areas, as when earth is carried by a current of water and deposited along the path of the current.
2. The collapse or 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 an 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 results in flooding as defined in subsection (1)(a) of this definition.
N. “Flood elevation study” means an examination, evaluation and determination of flood hazards and, if appropriate, corresponding water surface elevations, or an examination, evaluation and determination of mudslide (i.e., mudflow) and/or flood-related erosion hazards.
O. “Flood insurance rate map (FIRM)” means the official map on which the Federal Insurance Administration has delineated both the areas of special flood hazard and the risk premium zones applicable to the community. A FIRM that has been made available digitally is called a digital flood insurance rate map (DFIRM).
P. Flood Insurance Study (FIS). See “flood elevation study.”
Q. “Floodplain” or “flood-prone area” means any land area susceptible to being inundated by water from any source. See “flood or flooding.”
R. “Floodplain administrator” means the community official designated by title to administer and enforce the floodplain management regulations.
S. “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.
T. “Floodplain management regulations” means zoning ordinances, subdivision regulations, building codes, health regulations, special purpose ordinances (such as floodplain ordinances, grading ordinances and erosion control ordinances) and other applications of police power. The term describes such state or local regulations, in any combination thereof, which provide standards for the purpose of flood damage prevention and reduction.
U. “Flood proofing” means any combination of structural and nonstructural additions, changes, or adjustments to structures which reduce or eliminate risk of flood damage to real estate or improved real property, water and sanitary facilities, structures, and their contents.
V. “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 a designated height. Also referred to as “regulatory floodway.”
W. “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 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, and does not include long-term storage or related manufacturing facilities.
X. “Highest adjacent grade” means the highest natural elevation of the ground surface prior to construction next to the proposed walls of a structure.
Y. “Historic structure” means any structure that is:
1. Listed individually in the National Register of Historic Places (a listing maintained by the Department of the Interior) or preliminarily determined by the Secretary of the Interior as meeting the requirements for individual listing on the National Register;
2. Certified or preliminarily determined by the Secretary of the Interior as contributing to the historical significance of a registered historic district or a district preliminarily determined by the Secretary to qualify as a registered historic district;
3. Individually listed on a state inventory of historic places in states with historic preservation programs which have been approved by the Secretary of the Interior; or
4. Individually listed on a local inventory of historic places in communities with historic preservation programs that have been certified either:
a. By an approved state program as determined by the Secretary of the Interior; or
b. Directly by the Secretary of the Interior in states without approved programs.
Z. “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 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 PMC 23.40.140(A)(2).
AA. “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. The term “manufactured home” does not include a recreational vehicle.
BB. “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.
CC. “Mean sea level” means, for purposes of the National Flood Insurance Program, 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.
DD. “New construction” means, for the purposes of determining insurance rates, structures for which the start of construction commenced on or after the effective date of an initial flood insurance rate map or after December 31, 1974, whichever is later, and includes any subsequent improvements to such structures. For floodplain management purposes, “new construction” means structures for which the start of construction commenced on or after the effective date of a floodplain management regulation adopted by a community and includes any subsequent improvements to such structures.
EE. “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.
FF. “Recreational vehicle” means a vehicle which is:
1. Built on a single chassis;
2. Four hundred square feet or less when measured at the largest horizontal projection;
3. Designed to be self-propelled or permanently towable by a light-duty truck; and
4. Designed primarily not for use as a permanent dwelling but as temporary living quarters for recreational, camping, travel or seasonal use.
GG. Regulatory Floodway. See “floodway.”
HH. “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 streets 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. 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.
II. “Structure” means a walled and roofed building including a gas or liquid storage tank that is principally above ground, as well as a manufactured home.
JJ. “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 50 percent of the market value of the structure before the damage occurred.
KK. “Substantial improvement” means any reconstruction, rehabilitation, addition, or other improvement of a structure, the cost of which equals or exceeds 50 percent of the market value of the structure before the start of construction of the improvement. This term includes structures which have incurred substantial damage, regardless of the actual repair work performed. The term does not, however, include either:
1. Any project for improvement of a structure to correct existing violations of state or local health, sanitary, or safety code specifications which have been identified by the local code enforcement official and which are the minimum necessary to assure safe living conditions; or
2. Any alteration of a historic structure; provided, that the alteration will not preclude the structure’s continued designation as a historic structure.
LL. “Variance” 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.
MM. “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.
NN. “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.
OO. “Water surface elevation” means the height, in relation to the National Geodetic Vertical Datum (NGVD) of 1929, or other datum, of floods of various magnitudes and frequencies in the floodplains of coastal or riverine areas. (Ord. 2031 § 1 (Exh. A), 2020; Ord. 2018 § 3 (Exh. A), 2020; Ord. 1639 § 1, 2006).
23.40.060 Lands to which this chapter applies.
This chapter shall apply to all areas of special flood hazard within the jurisdiction of the city. (Ord. 2031 § 1 (Exh. A), 2020; Ord. 2018 § 3 (Exh. A), 2020; Ord. 1639 § 1, 2006).
23.40.070 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 King County and Incorporated Areas,” dated August 19, 2020, with accompanying flood insurance maps, is adopted by reference and declared to be a part of this chapter. The flood insurance study flood insurance rate maps are on file at Pacific City Hall. (Ord. 2031 § 1 (Exh. A), 2020; Ord. 2018 § 3 (Exh. A), 2020; Ord. 1639 § 1, 2006).
23.40.080 Penalties for noncompliance.
No structure or land shall hereafter be constructed, located, extended, converted or altered without full compliance with the terms of this chapter and other applicable regulations. Violation of the provisions of this chapter by failure to comply with any of its requirements (including violations of conditions and safeguards established in connection with conditions) shall constitute a misdemeanor. Any person who violates this chapter or fails to comply with any of its requirements shall upon conviction thereof be fined not more than $5,000 or imprisoned for not more than one year, or both, for each violation, and in addition shall pay all costs and expenses involved in the case. Nothing herein contained shall prevent the city from taking such other lawful action as is necessary to prevent or remedy any violation. (Ord. 2031 § 1 (Exh. A), 2020; Ord. 2018 § 3 (Exh. A), 2020; Ord. 1639 § 1, 2006).
23.40.090 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. 2031 § 1 (Exh. A), 2020; Ord. 2018 § 3 (Exh. A), 2020; Ord. 1639 § 1, 2006).
23.40.100 Interpretation.
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. 2031 § 1 (Exh. A), 2020; Ord. 2018 § 3 (Exh. A), 2020; Ord. 1639 § 1, 2006).
23.40.110 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 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. 2031 § 1 (Exh. A), 2020; Ord. 2018 § 3 (Exh. A), 2020; Ord. 1639 § 1, 2006).
23.40.113 Severability.
This chapter and the various parts thereof are hereby declared to be severable. Should any section of this chapter be declared by the courts to be unconstitutional or invalid, such decision shall not affect the validity of the chapter as a whole, or any portion thereof other than the section so declared to be unconstitutional or invalid. (Ord. 2031 § 1 (Exh. A), 2020).
23.40.115 Establishment of development permit.
A. Development Permit Required (44 CFR 60.3(b)(1)). A development permit shall be obtained before construction or development begins within any area of special flood hazard established in PMC 23.40.070. The permit shall be for all structures including manufactured homes, as set forth in PMC 23.40.050 and for all development including fill and other activities, also as set forth in PMC 23.40.050.
B. Application for Development Permit. Application for a development permit shall be made on forms furnished by the floodplain administrator 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:
1. Elevation in relation to mean sea level of the lowest floor (including basement) of all structures recorded on a current elevation certificate with Section B completed by the floodplain administrator;
2. Elevation in relation to mean sea level to which any structure has been floodproofed;
3. Where a structure is to be floodproofed, certification by a registered professional engineer or architect that the floodproofing methods for any nonresidential structure meet floodproofing criteria in PMC 23.40.140(B);
4. Description of the extent to which a watercourse will be altered or relocated as a result of proposed development;
5. Where a structure is proposed in a V, V1-30, or VE zone, a V-zone design certificate;
6. Where development is proposed in a floodway, an engineering analysis indicating no rise of the base flood elevation; and
7. Any other such information that may be reasonably required by the floodplain administrator in order to review the application. (Ord. 2031 § 1 (Exh. A), 2020).
23.40.117 Designation of the floodplain administrator.
The community development manager is hereby appointed to administer, implement, and enforce this chapter by granting or denying development permits in accordance with its provisions. The floodplain administrator may delegate authority to implement these provisions. (Ord. 2031 § 1 (Exh. A), 2020).
23.40.120 Duties and responsibilities of the community development manager.
The duties of the community development manager shall include:
A. Permit Review.
1. Review all permit applications to determine that the permit requirements of this chapter have been satisfied;
2. Review all permit applications 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 permit applications to determine if the proposed development is located in the floodway. If located in the floodway, assure that the encroachment provisions of PMC 23.40.150(A) are met and the site is reasonably safe from flooding.
B. Use of Other Base Flood Data. When base flood elevation data has not been provided (in A or V zones) in accordance with PMC 23.40.070, the community development manager shall obtain, review, and reasonably utilize any base flood elevation data available from a federal, state, or other source, in order to administer PMC 23.40.140 and 23.40.150. Any such information shall be consistent with the requirements of the Federal Insurance Administrator.
C. Information to Be Obtained and Maintained.
1. Where base flood elevation data is provided through the flood insurance study or as required in subsection B 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;
2. For all new or substantially improved floodproofed nonresidential structures where base flood elevation data is provided through the FIS, FIRM, or as required in subsection B of this section:
a. Obtain and maintain a record of the elevation (in relation to mean sea level) to which the structure was floodproofed. (44 CFR 60.3(b)(5)(ii)); and
b. Maintain the floodproofing certifications required in PMC 23.40.115(B)(3) (44 CFR 60.3(b)(5)(iii));
3. Certification required by PMC 23.40.150 (44 CFR 60.3(d)(3));
4. Records of all variance actions, including justification for their issuance;
5. Improvement and damage calculations;
6. Maintain for public inspection all records pertaining to the provisions of this chapter.
D. 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 Administrator; and
2. Assure that the flood carrying capacity of the altered or relocated portion of said watercourse is maintained.
3. Base flood elevations may increase or decrease resulting from physical changes affecting flooding conditions. As soon as practicable, but not later than six months after the date such information becomes available, the floodplain administrator shall notify the Federal Insurance Administrator of the changes by submitting technical or scientific data in accordance with 44 CFR 65.3. Such a submission is necessary so that upon confirmation of those physical changes affecting flooding conditions, risk premium rates and floodplain management requirements will be based upon current data.
4. Notify the Federal Insurance Administrator in writing of acquisition by means of annexation, incorporation or otherwise, of additional areas of jurisdiction.
E. Interpretation of FIRM Boundaries. The director shall 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 may appeal the interpretation as provided in Chapter 16.90 PMC. Such appeals shall be granted consistent with the standards of Section 1910.6 of the rules and regulations of the National Flood Insurance program (24 CFR 1909, etc.), to the extent such rules and regulations are applicable.
F. Review of Building Permits (44 CFR 60.3(a)(3)). Where elevation data is not available either through the FIS, FIRM, or from another authoritative source (subsection B of this section), applications for floodplain development 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.
G. Changes to Special Flood Hazard Area.
1. If a project will alter the BFE or boundaries of the SFHA, then the project proponent shall provide the community with engineering documentation and analysis regarding the proposed change. If the change to the BFE or boundaries of the SFHA would normally require a letter of map change, then the project proponent shall initiate, and receive approval of, a conditional letter of map revision (CLOMR) prior to approval of the development permit. The project shall be constructed in a manner consistent with the approved CLOMR.
2. If a CLOMR application is made, then the project proponent shall also supply the full CLOMR documentation package to the floodplain administrator to be attached to the floodplain development permit, including all required property owner notifications. (Ord. 2031 § 1 (Exh. A), 2020; Ord. 2018 § 3 (Exh. A), 2020; Ord. 1639 § 1, 2006).
23.40.130 Provisions 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, including those related to manufactured homes, shall be anchored to prevent flotation, collapse, or lateral movement of the structure resulting from hydrodynamic and hydrostatic loads including the effects of buoyancy (44 CFR 60.3(a)(3)(i)).
2. All manufactured homes shall 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 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.
C. Storage of Materials and Equipment.
1. The storage or processing of materials that could be injurious to human, animal, or plant life if released due to damage from flooding is prohibited in special flood hazard areas.
2. Storage of other material or equipment may be allowed if not subject to damage by floods and if firmly anchored to prevent flotation, or if readily removable from the area within the time available after flood warning.
D. Utilities.
1. All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of flood waters into the system;
2. New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of flood waters into the system and discharge from the systems into flood waters;
3. On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding; and
4. Water wells shall be located on high ground that is not in the floodway (WAC 173-160-171).
E. Development Proposals. All new development proposals, including subdivisions and manufactured home parks or subdivisions, 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; and
4. Include base flood elevation data for all proposals greater than 50 lots or five acres, whichever is the lesser.
F. Review of Building Permits. Where elevation data is not available either through the flood insurance study or from another authoritative source (PMC 23.40.120(B)), 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. 2031 § 1 (Exh. A), 2020; Ord. 2018 § 3 (Exh. A), 2020; Ord. 1639 § 1, 2006).
23.40.140 Specific standards.
In all areas of special flood hazard where base flood elevation (BFE) data has been provided as set forth in PMC 23.40.070, Basis for establishing the areas of special flood hazard, or PMC 23.40.120(B), Use of Other Base Flood Data, the following provisions are required:
A. Residential Construction.
1. In AE and A1-30 zones or other A-zoned areas where the BFE has been determined or can be reasonably obtained, new construction and substantial improvement of any residential structure shall have the lowest floor, including basement, elevated one foot or more above the BFE. Mechanical equipment and utilities shall be waterproof or elevated at least one foot above the BFE.
2. Fully enclosed areas below the lowest floor usable solely for parking, access or storage and 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 flood waters. 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 flood waters.
3. New construction and substantial improvement of any residential structure in an AO zone shall meet the requirements in PMC 23.40.170.
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 PMC 23.40.120(C);
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);
6. If located in an AO zone, the structure shall meet the requirements in PMC 23.40.170.
C. Critical Facility. Construction of new critical facilities shall be, to the extent possible, located outside the limits of the special flood hazard area (SFHA) (100-year floodplain). Construction of new critical facilities shall be permissible within the SFHA if no feasible alternative site is available. Critical facilities constructed within the SFHA shall have the lowest floor elevated to three feet or more above the level of the base flood elevation (100-year flood) at the site. Floodproofing and sealing measures must be taken to ensure that toxic substances will not be displaced by or released into flood waters. 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.
1. All manufactured homes to be placed or substantially improved within Zone AE on the community’s FIRM on sites:
a. Outside of a manufactured home park or subdivision;
b. In a new manufactured home park or subdivision;
c. In an expansion to an existing manufactured home park or subdivision;
d. 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 one foot above the base flood elevation; and be securely anchored to an adequately anchored 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 within Zone AE on the community’s FIRM 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 one foot above the base flood elevation level; or
b. The manufactured home chassis is supported by reinforced piers or other foundation elements of at least equivalent strength that are no less than 36 inches in height above grade and be securely anchored to an adequately anchored foundation system to resist flotation, collapse, and lateral movement. At a minimum, a reinforced pier would have a footing adequate to support the weight of the manufactured home under saturated soil conditions such as occur during a flood. In addition, if stacked concrete blocks are used, vertical steel reinforcing rods should be placed in the hollows of the blocks and those hollows filled with concrete or high strength mortar. In areas subject to high velocity flood waters and debris impact, cast-in-place reinforced concrete piers may be appropriate.
E. Recreational Vehicles. Recreational vehicles placed on sites within Zones A1-30, AH, and AE on the community’s FIRM shall:
1. Be on the site for fewer than 180 consecutive days;
2. 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
3. Meet the requirements of subsection D of this section and the elevation and anchoring requirements for manufactured homes.
F. Enclosed Area Below the Lowest Floor. If buildings or manufactured homes are constructed or substantially improved with fully enclosed areas below the lowest floor, the areas shall be used solely for parking of vehicles, building access, or storage.
G. Appurtenant Structures (Detached Garages and Small Storage Structures). For A Zones (A, AE, A1-30, AH, AO):
1. Appurtenant structures used solely for parking of vehicles or limited storage may be constructed such that the floor is below the BFE, provided the structure is designed and constructed in accordance with the following requirements:
a. Use of the appurtenant structure must be limited to parking of vehicles or limited storage;
b. The portions of the appurtenant structure located below the BFE must be built using flood resistant materials;
c. The appurtenant structure must be adequately anchored to prevent flotation, collapse, and lateral movement;
d. Any machinery or equipment servicing the appurtenant structure must be elevated or floodproofed to or above the BFE;
e. The appurtenant structure must comply with floodway encroachment provisions in PMC 23.40.150(A);
f. The appurtenant structure must be designed to allow for the automatic entry and exit of flood waters in accordance with subsection (A)(2) of this section;
g. The structure shall have low damage potential;
h. If the structure is converted to another use, it must be brought into full compliance with the standards governing such use; and
i. The structure shall not be used for human habitation.
2. Detached garages, storage structures, and other appurtenant structures not meeting the above standards must be constructed in accordance with all applicable standards in subsection (A)(1) of this section.
3. Upon completion of the structure, certification that the requirements of this section have been satisfied shall be provided to the floodplain administrator for verification.
H. All Crawlspace Construction. All crawlspaces that have enclosed areas or floors below the BFE must be:
1. Designed and adequately anchored to resist flotation, collapse and lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy;
2. Have openings that allow for the automatic entry and exit of floodwaters. The bottom of the flood opening can be no more than one foot above the lowest adjacent exterior grade and meet the requirements in PMC 23.40.140(A)(2);
3. Constructed with materials resistant to flood damage, including foundation walls, joists, insulation or other materials that will be below BFE;
4. Located in areas where flood velocities do not exceed five feet per second; and
5. Any building utility systems within the crawlspace must be elevated above the BFE or designed so that floodwaters cannot enter or accumulate within the system components during flood conditions.
Crawlspace construction is not permitted in V zones.
I. Below-Grade Crawlspaces. In addition to the above requirements, below-grade crawlspaces must be constructed so that:
1. The interior grade of the crawlspace below the BFE is not more than two feet below the lowest adjacent exterior grade;
2. The height of the below-grade crawlspace, measured from the interior grade of the crawlspace to the top of the crawlspace foundation wall, does not exceed four feet at any point;
3. An adequate drainage system to remove floodwaters from the interior area of the crawlspace is installed. (Ord. 2031 § 1 (Exh. A), 2020; Ord. 2018 § 3 (Exh. A), 2020; Ord. 1639 § 1, 2006).
23.40.150 Floodways.
Located within areas of special flood hazard established in PMC 23.40.070 are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of flood waters which carry debris, potential projectiles, and erosion potential, the following provisions apply:
A. Encroachments are prohibited, including fill, new construction, substantial improvements, and other development, unless certification by a registered professional engineer or architect is provided demonstrating through hydrologic and hydraulic analyses performed in accordance with standard engineering practice that encroachments shall not result in any increase in flood levels during the occurrence of the base flood discharge;
B. 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 50 percent of the market value of the structure either (a) before the repair, reconstruction, or repair is started, or (b) if the structure has been damaged, and is being restored, before the damage occurred. Work done on structures to comply with existing health, sanitary, or safety codes, or to structures identified as historic places shall not be included in the 50 percent.
C. If subsection A of this section is satisfied, all new construction and substantial improvements shall comply with all applicable flood hazard provisions of PMC 23.40.130, Provisions for flood hazard reduction.
D. Substantially Damaged Residences in Floodway.
1. For all substantially damaged residential structures, other than farmhouses, located in a designated floodway, the floodplain administrator may make a written request that the Department of Ecology assess the risk of harm to life and property posed by the specific conditions of the floodway. Based on analysis of depth, velocity, flood-related erosion, channel migration, debris load potential, and flood warning capability, the Department of Ecology may exercise best professional judgment in recommending to the local permitting authority repair, replacement, or relocation of a substantially damaged structure consistent with WAC 173-158-076. The property owner shall be responsible for submitting to the local government and the Department of Ecology any information necessary to complete the assessment. Without a favorable recommendation from the Department for the repair or replacement of a substantially damaged residential structure located in the regulatory floodway, no repair or replacement is allowed per WAC 173-158-070(1).
2. Before the repair, replacement, or reconstruction is started, all requirements of the NFIP, the state requirements adopted pursuant to Chapter 86.16 RCW, and all applicable local regulations must be satisfied. In addition, the following conditions must be met:
a. There is no potential safe building location for the replacement residential structure on the same property outside the regulatory floodway.
b. A replacement residential structure is a residential structure built as a substitute for a legally existing residential structure of equivalent use and size.
c. Repairs, reconstruction, or replacement of a residential structure shall not increase the total square footage of floodway encroachment.
d. The elevation of the lowest floor of the substantially damaged or replacement residential structure is a minimum of one foot higher than the BFE.
e . New and replacement water supply systems are designed to eliminate or minimize infiltration of flood water into the system.
f. New and replacement sanitary sewerage systems are designed and located to eliminate or minimize infiltration of flood water into the system and discharge from the system into the flood waters.
g. All other utilities and connections to public utilities are designed, constructed, and located to eliminate or minimize flood damage. (Ord. 2031 § 1 (Exh. A), 2020; Ord. 2018 § 3 (Exh. A), 2020; Ord. 1639 § 1, 2006).
23.40.160 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. 2031 § 1 (Exh. A), 2020; Ord. 2018 § 3 (Exh. A), 2020; Ord. 1639 § 1, 2006).
23.40.170 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 and manufactured homes 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 PMC 23.40.140(B)(3).
C. Adequate drainage paths are required around structures on slopes to guide flood waters around and away from proposed structures.
D. Recreational vehicles placed on sites within AO zones on the community’s FIRM shall either:
1. Be on the site for fewer than 180 consecutive days; and
2. 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
3. Meet the requirements of subsection A of this section and the elevation and anchoring requirements for manufactured homes. (Ord. 2031 § 1 (Exh. A), 2020; Ord. 2018 § 3 (Exh. A), 2020; Ord. 1639 § 1, 2006).
23.40.180 Variances
The variance criteria set forth in this section are based on the general principle of zoning law that variances pertain to a piece of property and are not personal in nature. A variance may be granted for a parcel of property with physical characteristics so unusual that complying with the requirements of this chapter would create an exceptional hardship to the applicant or the surrounding property owners. The characteristics must be unique to the property and not be shared by adjacent parcels. The unique characteristic must pertain to the land itself, not to the structure, its inhabitants, or the property owners.
It is the duty of the city to help protect its citizens from flooding. This need is so compelling and the implications of the cost of insuring a structure built below the base flood elevation are so serious that variances from the flood elevation or from other requirements in the flood ordinance are quite rare. The long-term goal of preventing and reducing flood loss and damage can only be met if variances are strictly limited. Therefore, the variance guidelines provided in this chapter are more detailed and contain multiple provisions that must be met before a variance can be properly granted. The criteria are designed to screen out those situations in which alternatives other than a variance are more appropriate.
A. Requirements for Variances.
1. Variances shall only be issued:
a. Upon a determination that the granting of a variance will not result in increased flood heights, additional threats to public safety, or extraordinary public expense, create nuisances, cause fraud on or victimization of the public, or conflict with existing local laws or ordinances;
b. For the repair, rehabilitation, or restoration of historic structures, upon a determination that the proposed repair or rehabilitation will not preclude the structure’s continued designation as a historic structure and the variance is the minimum necessary to preserve the historic character and design of the structure;
c. Upon a determination that the variance is the minimum necessary, considering the flood hazard, to afford relief;
d. Upon a showing of good and sufficient cause;
e. Upon a determination that failure to grant the variance would result in exceptional hardship to the applicant;
f. Upon a showing that the use cannot perform its intended purpose unless it is located or carried out in close proximity to water. This includes only facilities defined in PMC 23.40.050(W), the definition of “functionally dependent use.”
2. Variances shall not be issued within any floodway if any increase in flood levels during the base flood discharge would result.
3. 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 below the BFE, provided the procedures of PMC 23.40.115 and 23.40.130 have been fully considered. As the lot size increases beyond one-half acre, the technical justification required for issuing the variance increases.
B. Variance Criteria. In considering variance applications, the city shall consider all technical evaluations, all relevant factors, all 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 to 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 proposed 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 flood waters 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, water system, and streets and bridges.
C. Additional Requirements for the Issuance of a Variance.
1. Any applicant to whom a variance is granted shall be given written notice over the signature of a community official that:
a. The issuance of a variance to construct a structure below the BFE will result in increased premium rates for flood insurance up to amounts as high as $25.00 for $100.00 of insurance coverage; and
b. Such construction below the BFE increases risks to life and property.
2. The floodplain administrator shall maintain a record of all variance actions, including justifications for their issuance.
3. The floodplain administrator shall condition the variance as needed to ensure that the requirements and criteria of this chapter are met.
4. Variances as interpreted in the NFIP 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. (Ord. 2031 § 1 (Exh. A), 2020).
23.40.190 Acronyms.
• (ASCE) American Society of Civil Engineers;
• (BFE) base flood elevation;
• (CFR) Code of Federal Regulations;
• (CLOMR) conditional letter of map revision;
• (DFIRM) digital flood insurance rate map;
• (FIRM) flood insurance rate map;
• (FIS) flood insurance study;
• (LOMA) letter of map amendment;
• (LOMR-F) letter of map revision based on fill;
• (NFIP) National Flood Insurance Rate Program;
• (PMC) Pacific Municipal Code;
• (RCW) Revised Code of Washington;
• (SFHA) special flood hazard area;
• (WAC) Washington Administrative Code. (Ord. 2031 § 1 (Exh. A), 2020).
Ord. 2018 is in effect from July 13, 2020, until January 13, 2021. Section 5 of the ordinance states, in part, “The interim Zoning Code amendments adopted by this Ordinance shall remain in effect for a period of six months from the effective date and shall automatically expire unless the same are extended as provided in RCW 36.70A.390 and RCW 35A.63.220 prior to that date, or unless the same are repealed or superseded by permanent amendments prior to that date.”