Chapter 3.20 FLOOD HAZARD DEVELOPMENT*

The legislature of the state of Washington has delegated the responsibility to local governmental units to adopt regulations designed to promote the public health, safety, and general welfare of its citizenry. Therefore, the Chelan County board of commissioners does ordain as follows. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.020 Title.

This chapter and amendments thereto shall be known and may be cited as “The Chelan County Flood Hazard Development Code.” (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.030 Applicability.

The provisions contained herein shall be applicable to land within the unincorporated areas of Chelan County that have been designated as special flood hazard areas as defined in Section 3.20.090. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.040 Exemptions.

The following uses and activities are exempt from the provisions of this chapter:

(1) The maintenance of aboveground utilities and facilities, such as replacing power lines and utility poles;

(2) Normal agricultural practices on existing agricultural areas involving plowing, storing of materials, etc., normal to operation of a farm (other than new structures);

(3) Removal of noxious weeds, hazard trees, and replacement of nonnative vegetation with native vegetation;

(4) Routine maintenance of existing landscaping that does not involve grading, excavation, or filling;

(5) Normal road maintenance, such as filling potholes, repaving, installing sign and traffic signals, but not including any expansion; and

(6) Normal maintenance of a levee or other flood control facility as prescribed in the operations and maintenance plan for the facility. Normal maintenance does not include repair from flood damage, any expansion of the prism, face or toe expansion, or the addition of material for protection or armor. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.050 Purpose.

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

(1) Protect human life and health;

(2) Minimize expenditure of public moneys and reduce the need for uneconomical flood control projects;

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

(4) Minimize prolonged business interruptions;

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

(6) Help maintain a stable tax base by providing for the sound use and development of flood hazard areas so as to minimize future flood loss;

(7) Ensure that potential buyers are aware that the property is located in a flood hazard area;

(8) Ensure that those who occupy the flood hazard areas assume responsibility for their own actions; and

(9) Satisfy the requirements established by the Federal Emergency Management Agency as failure to do so would jeopardize federal financial support to the county and its citizens. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.060 Warning and disclaimer of liability.

This chapter does not imply that the lands outside of flood hazard areas, or uses permitted within such areas, shall be free from flooding or flood damage, nor does this chapter imply that the compliance herewith or related resolutions will in all instances protect property from flood damage. This chapter shall not create liability on Chelan County, or any officer or employee thereof, for any flood damage that results from reliance on this chapter or any administrative decision lawfully made thereunder. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.070 Interpretation.

In the interpretation and application of this chapter, all provisions shall be considered as minimum requirements, shall be liberally construed in favor of Chelan County, and deemed neither to limit or repeal any other powers granted under state statutes. Further, this chapter is not intended to repeal, abrogate, or diminish the effect of any existing easement, covenant, or deed restriction. However, where conditions imposed by this chapter are less restrictive than comparable conditions imposed by any other resolutions or regulations, the provisions which are more restrictive shall apply. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.080 Floodplain administrator.

The director of the Chelan County department of community development, or designated representative, hereinafter referred to as the floodplain administrator, is vested with the duty of administration of the provisions of this chapter within the unincorporated area of Chelan County, and shall prepare and require the use of such forms deemed appropriate for the proper administration of these requirements. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.090 Flood hazard areas established.

The areas of special flood hazard identified by the Federal Insurance Administrator in a scientific and engineering report titled “The Flood Insurance Study for Chelan County, Washington, Unincorporated Areas” dated February 4, 1981, and revised September 30, 2004, with accompanying flood insurance rate maps dated February 4, 1981, June 5, 1989, July 2, 2002, and September 30, 2004, and any subsequent revisions thereto are hereby adopted by reference and declared to be part of this chapter. The flood insurance study is on file at the Department of Community Development, 316 Washington Street, Suite 301, Wenatchee, Washington 98801.

The best available information for flood hazard area identification as outlined in Section 3.20.100 shall be the basis for regulation until a new flood insurance rate map is issued that incorporates data utilized under Section 3.20.200.

The board of county commissioners adopts the Federal Emergency Management Agency’s modified base flood elevations and revised map panels 5300115 0625 D, 0779 D, 0800 D, 2730 D, 2740 D, 2745 D, 2763 D, 2764 D, and 2768 D, dated September 30, 2004, for the unincorporated areas of Chelan County, Washington. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.100 Use of other base flood data.

When base flood elevation data has not been provided in accordance with Section 3.20.090, Flood hazard areas established, the floodplain administrator shall obtain, review and reasonably utilize any base flood elevation data and floodway data available from a federal, state or other source, in order to administer Article IV of this chapter, Improvement Standards, Sections 3.20.220 through 3.20.320, including Section 3.20.300, Regulatory floodways. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.110 Severability.

Should any section, paragraph, sentence, or word of this chapter, or of any of the code and resolutions herein referenced, or the application to any person or circumstances be held invalid in a court of competent jurisdiction for any reason, the remainder of this chapter or the application of the provision to other persons or circumstances shall not be affected. (Res. 2020-63 (Att. A) (part), 6/9/20).

Article II. Definitions

3.20.120 Definitions.

Whenever the following words and phrases appear in this chapter, they shall be given the meanings attributed to them by this section. When not inconsistent with the context, words used in the present tense shall include the future; the singular shall include the plural, and the plural the singular; the word “shall” is always mandatory and the word “may” indicates a use of discretion in making a decision.

“Alteration of watercourse” means any action that will change the location of the channel occupied by water within the banks of any portion of a riverine water body.

“Appeal” means a request for review of the interpretation of any provisions of this chapter.

“Area of shallow flooding” shall mean a designated AO zone on the flood insurance rate map (FIRM). Those areas are characterized by base flood depths ranging from one to three feet; the lack of a clearly defined channel; the path of flooding is unpredictable and indeterminate; and velocity flow may be evident.

“Area of special flood hazard” is the land in the floodplain within unincorporated Chelan County subject to a one percent or greater chance of flooding in any given year. Designation on flood insurance rate maps (FIRMs) always includes the letter A. Also known as “special flood hazard area.”

“ASCE 24” means the most recently published version of ASCE 24, Flood Resistant Design and Construction, published by the American Society of Civil Engineers.

“Base flood” means the flood having a one percent chance of being equaled or exceeded in any given year (also referred to as the “one-hundred-year flood”).

“Base flood elevation (BFE)” means that elevation to which floodwater can be expected to rise during a base flood.

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

Building. See “Structure.”

“Critical facility” means a facility for which even a slight chance of flooding may be too great. Critical facilities include but are not limited to schools, nursing homes, hospitals, police, fire and emergency response installations, installations which produce, use, or store hazardous materials or hazardous waste.

“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 located within the area of special flood hazard.

“Elevation certificate” means an administrative tool of the National Flood Insurance Program (NFIP) that can be used to provide elevation information, to determine the proper insurance premium rate, and to support a request for a letter of map amendment (LOMA) or letter of map revision based on fill (LOMR-F).

“Essential facility” has the same meaning as “essential facility” defined in ASCE 24. Table 1-1 in ASCE 24-14 further identifies building occupancies that are essential facilities.

“Excavation” is the mechanical removal of earth material.

“Farmhouse” means a single-family dwelling located on a farm site where resulting agricultural products are not produced for the primary consumption or use by the occupants and the farm owner.

“Fill” is a deposit of earth material placed by artificial means.

“Flood or flooding” means:

(A) A general and temporary condition of partial or complete inundation of normally dry land areas from:

(i) The overflow of inland or tidal waters.

(ii) The unusual and rapid accumulation or runoff of surface waters from any source.

(iii) Mudslides (i.e., mudflows) which are proximately caused by flooding as defined in subsection (A)(ii) 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; or

(B) 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 (A)(i) of this definition.

“Flood damage” means harmful inundation, water erosion of soil, stream banks and beds, stream channel shifting and changes, harmful deposition by water of eroded and shifting soils and debris upon property or in the beds of streams or other bodies of water, damages by high water to public roads, highways, bridges, utilities and to works built for protection against floods or inundation, the interruption by floods of travel, communication and commerce, and all other high water influences and results which injuriously affect the public health and the safety of property.

Flood Elevation Study. See “Flood insurance study (FIS)”.

“Flood insurance rate map (FIRM)” means the official map on which the Federal Insurance Administrator has delineated both the flood hazard areas and the risk premium zones applicable to Chelan County. A FIRM that has been made available digitally is called a digital flood insurance rate map (DFIRM).

“Flood insurance study (FIS)” 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, also known as a flood elevation study.

“Floodplain or flood-prone area” means any land area susceptible to being inundated by water from any source. See “Flood or flooding.”

“Floodplain administrator” shall mean the director of the Chelan County department of community development, or designated representative, who is vested with the duty of administering the provisions of this chapter.

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

“Floodplain management regulations” means zoning ordinances, subdivision regulations, building codes, health regulations, special purpose ordinances (such as floodplain ordinance, grading ordinance and erosion control ordinance) and other application 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.

“Floodproofing” means any combination of structural and nonstructural additions, changes, or adjustments to structures which reduce or eliminate flood damage to real estate or improved real property, water and sanitary facilities, structures and their contents. Floodproofed structures are those that have the structural integrity and design to be impervious to floodwater below the base flood elevation.

“Floodway” means the channel of the 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 known as “regulatory floodway.”

“Functionally dependent use” means a use which cannot perform its intended purpose unless it is located or carried out in close proximity to water. The term 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.

“Highest adjacent grade” means the highest natural elevation of the ground surface prior to construction next to the proposed walls of the structure.

“Historic structure” means any structure that is:

(A) 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;

(B) 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;

(C) 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

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

(i) By an approved state program as determined by the Secretary of the Interior; or

(ii) Directly by the Secretary of the Interior in states without approved programs.

“Lowest floor” means the lowest floor of the lowest enclosed area, including basement. An unfinished or flood resistant enclosure, useable solely for parking of vehicles, building access, or storage, in an area other than a basement area, is not considered the lowest floor of a building; provided, that such enclosure is not built so as to render the structure in violation of the applicable nonelevation requirements of this chapter.

“Manufactured home” means a structure, transportable in one or more sections, which is built on a permanent chassis and is designed for use with or without a permanent foundation when 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 or more manufactured home lots for rent or sale.

“Mean sea level” means, for the purposes of the National Flood Insurance Program, the vertical datum to which base flood elevations shown on a community’s flood insurance rate map are referenced.

“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.

“Reasonably safe from flooding” means development that is designed and built to be safe from flooding based on consideration of current flood elevation studies, historical data, high water marks and other reliable data known to the community. In unnumbered A zones where flood elevation information is not available and cannot be obtained by practicable means, “reasonably safe from flooding” means that the lowest floor is at least three feet above the highest adjacent grade for residential structures or at least two feet above grade for nonresidential structures.

“Recreational vehicle” means a vehicle which is: (A) built on a single chassis; (B) four hundred square feet or less when measured at the largest horizontal projection; (C) designed to be self-propelled or permanently towable by a light duty truck; and (D) designed primarily not for use as a permanent dwelling but as a temporary living quarters for recreational, camping, travel, or seasonal use.

“Start of construction” includes substantial improvement, and means the date the building permit was issued, provided the actual start of construction, repair, reconstruction, rehabilitation, addition, placement or other improvement was within one hundred eighty 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, for floodplain management purposes, a walled and roofed building, including a gas or liquid storage tank, that is principally above ground, as well as a manufactured home.

“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 of the market value of the structure before the damage occurred.

“Substantial improvement” means any reconstruction, rehabilitation, addition, or other improvement of a structure, the cost of which equals or exceeds fifty 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:

(A) Any project for improvement of a structure to correct existing violations of state or local health, sanitary, or safety code specifications that have been previously identified by the local code enforcement official and that are the minimum necessary to assure safe living conditions; or

(B) Any alteration of a “historic structure,” provided that the alteration will not preclude the structure’s continued designation as a “historic structure.”

“Variance” means a grant of relief by a community from the terms of a floodplain management regulation.

“Violation” means the failure of a structure or other development to be constructed or implemented in conformance with the community’s applicable floodplain development regulations.

“Water surface elevation” means the height, in relation to the National Geodetic Vertical Datum (NGVD) of 1929 (or other datum, where specified) of floods of various magnitudes and frequencies in the floodplains of coastal or riverine areas. (Res. 2020-85 (Exh. A) (part), 8/25/20; Res. 2020-63 (Att. A) (part), 6/9/20).

Article III. Administration

3.20.130 Development permit required.

A development permit shall be obtained before construction or development begins within any area of special flood hazard established in this chapter. The permit shall be for all structures including manufactured homes, as set forth in Section 3.20.120, Definitions, and for all development including fill and other activities, also set forth in Section 3.20.120, Definitions. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.140 Floodplain delineation.

If there is any question as to the location of the boundaries of the special flood hazard area or floodway in relation to the proposed development, the floodplain administrator may require the applicant provide, at the expense of the applicant, a floodplain delineation prepared by a licensed professional land surveyor which shows the boundaries of the special flood hazard area and floodway and ground elevations on a site plan. However, all development shall be reasonably safe from flooding. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.150 Information to be submitted.

Application for a development permit shall be made on a form furnished by the community development department. The following information shall be submitted to the floodplain administrator in order to apply for a floodplain development permit prior to undertaking any development or substantial improvement in the special flood hazard area. These items shall be submitted in addition to that information necessary to obtain other permits, as well as for those developments and substantial improvements which require no other permit approvals. Other information may be reasonably required by the floodplain administrator in order to review the application.

(1) The nature, location, dimensions, and ground elevations of the project site;

(2) Typical cross-sections showing existing ground elevations, proposed ground elevations and proposed elevations of the crawlspace and/or finished floor, if applicable;

(3) Where appropriate, proposed land contours if development involves grading, cutting, filling or other alterations of land contours. When required, contours shall be at two-foot intervals for land with a slope of zero to five percent and five-foot intervals for land with a slope of five percent and greater;

(4) Dimensions and locations of existing structures which will be maintained;

(5) Dimensions and locations of proposed structures;

(6) Identify the source, composition and volume of fill materials;

(7) Identify composition and volume of any excavated materials and identify proposed disposal area;

(8) Location of existing and proposed utilities such as sewer, septic tank, drainfield, water, gas and electricity;

(9) An elevation certificate for all new or substantially improved structures, prepared by a licensed professional land surveyor;

(10) Description of the extent to which any watercourse is proposed for alteration or relocation as the result of a proposed development;

(11) Boundaries of the special flood hazard area and floodway in relation to the proposed structures or project;

(12) Where development is proposed in a floodway, an engineering analysis demonstrating no rise of the base flood elevation; and

(13) 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 Section 3.20.260(2). (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.160 Elevation certificates.

Three elevation certificates are required throughout the building process for all new and substantially improved structures, unless the floodplain administrator determines an elevation certificate is not necessary for a specific structure:

(1) For construction drawings prior to review of a building permit;

(2) For a building under construction prior to scheduling of an underfloor inspection, or equivalent, but always before vertical construction; and

(3) For finished construction prior to issuance of a certificate of occupancy or final approval. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.170 Administrative review.

The floodplain administrator shall review information submitted for development permits to determine the following:

(1) The requirements of this chapter have been satisfied;

(2) All necessary permits which require prior approval have been obtained from federal, state or local government agencies;

(3) If the proposed development is located in the floodway, assure that the provisions of Section 13.20.300 are met;

(4) In areas where a floodway has not been designated, require that no new construction, substantial improvements, or other development (including fill) shall be permitted within Zones A1-30 and AE unless it is demonstrated that the cumulative effect of the proposed development, when combined with all other existing and anticipated development, will not increase the water surface elevation of the base flood more than one foot at any point within the community. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.180 Floodplain administrator’s responsibilities.

It shall be the duty of the floodplain administrator or designee to:

(1) Grant or deny development permits;

(2) Make interpretations as to the exact location of the boundaries of special flood hazard areas;

(3) Obtain and record the actual (as-built) elevation (in relation to mean sea level) of the lowest floor (including basement) of all new or substantially improved structures, and whether or not the structure contains a basement, on the form provided by FEMA known as an elevation certificate;

(4) For all new or substantially improved floodproofed nonresidential structures;

(A) Verify and record the actual elevation (in relation to mean sea level) to which the structure was floodproofed;

(B) Maintain the floodproofing certifications required in this chapter;

(5) Maintain for public inspection all records pertaining to the provisions of this chapter.

(A) Improvement and damage calculations;

(B) Records of all variance actions, including justification for their issuance;

(6) Notify FEMA when annexations occur in the special flood hazard area;

(7) Notify FEMA within six months of technical or scientific data becoming available confirming the occurrence of physical changes that increase or decrease the base flood elevation. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.190 Alteration of watercourse.

Whenever a watercourse is to be altered or relocated, the floodplain administrator shall:

(1) Notify adjacent communities and the Washington State Department of Ecology prior to any alteration or relocation of a watercourse, and submit evidence of such notification to the Federal Insurance Administrator through appropriate notification means; and

(2) Assure that the flood carrying capacity of the altered or relocated portion of said watercourse is maintained. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.200 Review of building permits.

Where elevation data is not available either through the flood insurance study or from another authoritative source identified in this chapter, 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. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.210 Appeals.

When it is alleged that there is an error in a requirement, decision or determination made by the floodplain administrator in the enforcement or administration of this chapter, an appeal shall be filed following the administrative appeals provisions of Section 14.12.010. The administrative appeal shall be filed with the community development department and heard as an open record hearing by the Chelan County hearing examiner at a public meeting. In passing upon such applications, the hearing examiner shall consider all technical evaluations, all relevant factors, standards specified in other sections of this chapter, and the provisions of Sections 3.20.380(2)(A)(i) through (xi). (Res. 2020-63 (Att. A) (part), 6/9/20).

Article IV. Improvement Standards

3.20.220 General.

The standards contained herein are the minimum consistent with the protection of the general public health, safety, and welfare and shall apply to all special flood hazard areas. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.230 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 and shall be installed using methods and practices that minimize flood damage.

(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. For more detailed information, refer to guidebook, FEMA-85, “Manufactured Home Installation in Flood Hazard Areas.” (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.240 Construction materials and methods.

(1) All new construction and substantial improvements shall be constructed using methods and practices that minimize flood damage and shall be constructed with materials and utility equipment resistant to flood damage.

(2) All building utilities shall be protected from flooding and designed to prevent water from entering or accumulating within the components during conditions of flooding. Building machinery and equipment, such as elevators, furnaces, hot water heaters, heat pumps, and air conditioners, shall be elevated or floodproofed to the same elevation required of the lowest floor. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.250 Utilities.

The following standards shall apply to all utilities within the special flood hazard area:

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

(2) Water wells shall be located on high ground that is not in the floodway;

(3) Manhole covers shall be designed so as to seal themselves, thereby preventing infiltration of floodwaters;

(4) New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration by floodwaters into the system and prevent the discharge from the sewage systems into floodwaters and contamination during flooding. On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding. The compliance with these requirements shall be as directed by the Chelan-Douglas health district;

(5) All utility systems shall be underground except where the presence of bedrock or other obstructions makes undergrounding prohibitive; provided, that electric transmission lines in excess of fifteen KV are exempt from undergrounding. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.260 Specific standards for construction activities.

In all areas of special flood hazard where base flood elevation data has been provided as set forth in Section 3.20.090, Flood hazard areas established, or Section 3.20.100, Use of other base flood data, the following provisions are required:

(1) Residential Construction.

(A) New construction or substantial improvement of any residential structure shall require the lowest floor including basement to be elevated to three feet or higher above the base flood elevation.

(B) Where new construction or substantial improvement is to occur in a special flood hazard area designated as an AO zone, the lowest floor including basement shall be elevated above the highest adjacent grade of the building site, to three feet or more above the depth number specified on the FIRM (at least three feet if no depth number is specified). In an AO zone adequate drainage paths shall be provided on slopes to guide floodwaters around and away from proposed structures.

(C) Where velocities are noted on the FIRM consideration shall be given to mitigating the effects of these velocities in proper construction techniques and methods.

(D) New construction and substantial improvement of any residential structure in an unnumbered A zone for which a base flood elevation is not available and cannot be reasonably obtained shall be reasonably safe from flooding, but in all cases the lowest floor shall be at least three feet above the highest adjacent grade.

(E) Fully enclosed areas below the lowest floor that are useable 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 floodwaters. Designs must meet the following minimum criteria:

(i) A minimum of two openings on at least two sides of the enclosed area 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;

(ii) The bottom of all openings shall be no higher than one foot above grade;

(iii) Openings may be equipped with screens, louvers or other coverings or devices; provided, that they permit the automatic entry and exit of floodwaters; and

(iv) A garage attached to a residential structure, used only for parking, storage, or building entry, may be constructed with the garage floor slab below the base flood elevation and must be designed to allow for the automatic entry and exit of floodwaters.

(F) The elevation of the interior crawlspace grade must be at or above the lowest elevation of the exterior grade; provided, that below-grade crawlspace foundations may be allowed when all of the following conditions are met:

(i) The interior grade of the crawlspace below the base flood elevation is no more than two feet below the lowest adjacent exterior grade; and

(ii) 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; and

(iii) The crawlspace contains an adequate drainage system that removes floodwaters from the interior of the crawlspace, such as natural drainage through porous, well-drained soils, and/or constructed drainage systems such as perforated pipes, drainage tiles or gravel or crushed stone drainage by gravity or mechanical means; and

(iv) Any building utility systems within the crawlspace are elevated to the flood protection elevation or designed so that floodwaters cannot enter or accumulate within the system components during flood conditions. In particular, all ductwork is elevated above the flood protection elevation or sealed from floodwaters; and

(v) The velocity of floodwaters at the site does not exceed five feet per second for any crawlspace; and

(vi) All other minimum criteria set forth in this section are satisfied.

(2) Nonresidential Construction.

(A) New construction or the substantial improvement of any commercial, industrial or other nonresidential structure shall require the lowest floor, including basement, to be elevated to or above one foot higher than the base flood elevation.

(B) Where new construction or substantial improvement is to occur in a special flood hazard area designated as an AO zone, the lowest floor including basement shall be elevated above the highest adjacent grade of the building site, to one foot or more above the depth number specified on the FIRM (at least two feet if no depth number is specified). In an AO zone adequate drainage paths shall be provided on slopes to guide floodwaters around and away from proposed structures.

(C) Where velocities are noted on the FIRM, consideration shall be given to mitigating the effects of these velocities in proper construction techniques and methods.

(D) New construction and substantial improvement of any nonresidential structure in an unnumbered A zone for which a base flood elevation is not available and cannot be reasonably obtained shall be either floodproofed or have the lowest floor be at least two feet above the highest adjacent grade.

(E) Fully enclosed areas below the lowest floor that are useable solely for parking, access or storage and that are subject to flooding shall be prohibited, or shall be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of floodwaters. Designs shall meet or exceed the following criteria:

(ii) The bottom of all openings shall be no higher than one foot above grade;

(iii) Openings may be equipped with screens, louvers or other coverings or devices; provided, that they permit the automatic entry and exit of floodwaters; and

(F) As an alternative to the elevation of nonresidential structures, such structures, with attendant utility and sanitary facilities, shall:

(i) Be floodproofed so that below one foot above the base flood elevation the structure is watertight with walls substantially impermeable to the passage of water;

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

(iii) 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 the provisions of this section based on their development and/or review of the structural design, specifications and plans. Such certifications shall be provided to and maintained by the floodplain administrator;

(iv) Applicants who are 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 the base flood level will be rated as one foot below).

(3) Accessory Structures.

(A) Accessory structures used solely for parking of vehicles or limited storage may be constructed such that the lowest floor is below the base flood elevation, provided the structure is designed and constructed in accordance with the following requirements:

(i) Use of the accessory structure must be limited to parking of vehicles or limited storage;

(ii) The portions of the accessory structure located below the base flood elevation must be built using flood resistant materials;

(iii) The accessory structure must be adequately anchored to prevent flotation, collapse, and lateral movement;

(iv) Any machinery or equipment servicing the accessory structure must be elevated or floodproofed to or above the base flood elevation;

(v) The accessory structure must comply with floodway encroachment provisions in Section 3.20.300;

(vi) The accessory structure must be designed to allow for the automatic entry and exit of floodwaters in accordance with subsections (1)(E)(i) through (iii) of this section;

(vii) The structure shall have low damage potential;

(viii) If the structure is converted to another use, it must be brought into full compliance with the standards governing such use; and

(ix) The structure shall not be used for human habitation.

(B) Detached garages, storage structures, and other accessory structures not meeting the above standards must be constructed in accordance with all applicable standards in subsection (2) of this section.

(C) Upon completion of the structure, certification that the requirements of this section have been satisfied shall be provided to the floodplain administrator for verification. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.270 Grading and filling.

If grading or other activity will displace any effective flood storage volume, compensatory storage shall be created on site, or off site if legal arrangements can be made, to assure that the effective compensatory storage volume will be preserved over time, in equivalent volume, at equivalent elevations to that being displaced. Compensatory storage areas must be hydraulically connected to the source of flooding. Filling and grading shall be in compliance with the most current version of FEMA Technical Bulletin No. 10, “Ensuring That Structures Built on Fill In or Near Special Flood Hazard Areas Are Reasonably Safe From Flooding.” (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.280 Manufactured homes.

The following standards shall be applicable for all new, replacement, or substantially improved manufactured home installations and for any existing manufactured home which has incurred substantial damage as the result of flood.

(1) Manufactured homes in special flood hazard areas shall be elevated on a permanent foundation consisting of a minimum of reinforced concrete footings and piers such that the lowest floor of the manufactured home is elevated to at least three feet above the base flood elevation and adequately anchored to resist flotation, collapse and lateral movement. In flood hazard areas designated as an AO zone the lowest floor of the manufactured home shall be elevated above the highest adjacent grade of the building site, to three feet or more above the depth number specified on the FIRM. Where hazardous velocities are noted on the FIRM, consideration shall be given to mitigating the effects of these velocities through engineering design.

(2) Manufactured homes constructed with a block skirting or other solid perimeter wall shall meet the same standards for space below the lowest floor as provided in Section 3.20.260(1)(E). (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.290 Recreational vehicles.

All recreational vehicles located in the special flood hazard area shall not be on site for more than one hundred eighty consecutive days and must be licensed and ready for highway use, on its wheels or jacking system, attached to sites only by quick disconnect type utilities and security devices, and have no permanently attached additions. Recreational vehicles that do not meet these requirements must meet the elevation and anchoring requirements for manufactured homes. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.300 Regulatory floodways.

Located within areas of special flood hazard established in Section 3.20.090 are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of floodwaters that can carry debris, and increase erosion potential, the following provisions apply:

(1) No Rise Standard. Prohibit encroachments, including fill, new construction, substantial improvements, and other development, unless certification by a registered professional engineer is provided demonstrating through hydrologic and hydraulic analyses performed in accordance with standard engineering practice that the proposed encroachment would not result in any increase in flood levels during the occurrence of the base flood discharge.

(2) Residential Construction in Floodways. Construction or reconstruction of residential structures is prohibited within designated floodways, except for (A) repairs, reconstruction, or improvements to a structure that do not increase the ground floor area; and (B) repairs, reconstruction, or improvements to a structure, the cost of which does not exceed fifty percent of the market value of the structure either (i) before the repair or reconstruction is started, or (ii) 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 that have been identified by the local code enforcement official and that are the minimum necessary to assure safe living conditions, or to structures identified as historic places, may be excluded from the fifty percent.

(A) Replacement of Farmhouses in Floodway. Repairs, reconstruction, replacement, or improvements to existing farmhouse structures located in designated floodways and that are located on lands designated as agricultural lands of long-term commercial significance under RCW 36.70A.170 may be permitted subject to the following:

(i) The new farmhouse is a replacement for an existing farmhouse on the same farm site;

(ii) There is no potential building site for a replacement farmhouse on the same farm outside the designated floodway;

(iii) Repairs, reconstruction, or improvements to a farmhouse shall not increase the total square footage of encroachment of the existing farmhouse;

(iv) A replacement farmhouse shall not exceed the total square footage of encroachment of the farmhouse it is replacing;

(v) A farmhouse being replaced shall be removed, in its entirety, including foundation, from the floodway within ninety days after occupancy of a new farmhouse;

(vi) For substantial improvements and replacement farmhouses, the elevation of the lowest floor of the improvement and farmhouse respectively, including basement, is a minimum of three feet higher than the base flood elevation;

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

(viii) New and replacement sanitary sewerage systems are designed and located to eliminate or minimize infiltration of floodwater into the system and discharge from the system into the floodwaters; and

(ix) All other utilities and connections to public utilities are designed, constructed, and located to eliminate or minimize flood damage.

(B) Substantially Damaged Residences in Floodway.

(i) 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).

(ii) 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 three feet higher than the base flood elevation.

(e) New and replacement water supply systems are designed to eliminate or minimize infiltration of floodwater into the system.

(f) New and replacement sanitary sewerage systems are designed and located to eliminate or minimize infiltration of floodwater into the system and discharge from the system into the floodwaters.

(g) All other utilities and connections to public utilities are designed, constructed, and located to eliminate or minimize flood damage.

(3) All other building standards apply in the floodway.

If subsection (1) of this section is satisfied or construction is allowed pursuant to subsection (2) of this section, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of this article. (Res. 2020-85 (Exh. A) (part), 8/25/20; Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.310 Critical facilities.

Construction of new critical facilities shall be, to the extent possible, located outside the limits of the base floodplain. Construction of new critical facilities shall be permissible within the base floodplain if no feasible alternative site is available. Critical facilities constructed within the base floodplain shall have the lowest floor elevated to three feet or more above the level of the same flood elevation at the site. Floodproofing and sealing measures must be taken to ensure that toxic substances will not be displaced by or released into floodwaters. Access routes elevated to or above the level of the base floodplain shall be provided to all critical facilities to the extent possible. Compliance with these requirements must be certified by a registered professional engineer or architect. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.320 Livestock sanctuaries.

Elevated areas for the purpose of creating a flood sanctuary for livestock are allowed on farm units where livestock is allowed. Livestock flood sanctuaries shall be sized appropriately for the expected number of livestock and be elevated sufficiently to protect livestock. Proposals for livestock flood sanctuaries shall meet all procedural and substantive requirements of this chapter. (Res. 2020-63 (Att. A) (part), 6/9/20).

Article V. Development Proposals

3.20.330 Development proposals.

All new development proposals, including subdivisions and manufactured home parks, shall comply with the following:

(1) The development shall be consistent with the need to minimize flood damage;

(2) The development shall locate and construct public/private utilities to minimize flood damage;

(3) The development 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 authorized source, it shall be generated for subdivision proposals and other proposed development of fifty lots or five acres, whichever is the lesser;

(5) For subdivisions, a designated buildable area in each lot shall be provided for outside the floodway and be identified on the face of the final plat, short plat, survey or binding site plan mylar, unless the lot is designated for open space or protected by a conservation easement;

(6) Roads necessary to access permitted improvements may cross the floodway if no reasonable route exists outside the floodway;

(7) Open space lots may be located within the one-hundred-year floodplain;

(8) Pursuant to Section 12.08.100, no development or subdivision or part thereof shall be approved if related improvements such as levees, fills, or other features will individually or collectively significantly increase flood flows, heights, velocities or potential for damage. All development and subdivisions shall be consistent with and in conformance with the requirements of this chapter;

(9) If a development or subdivision or portion thereof lies within the one-hundred-year floodplain, conformance with all applicable local, state and federal requirements shall be required including, but not limited to, this chapter, the Chelan County zoning resolution, the Chelan County subdivision resolution, the Chelan County critical areas overlay districts, and the Chelan County shoreline master program;

(10) If a development proposal will alter the base flood elevation or boundaries of the special flood hazard area, then the project proponent shall provide the floodplain administrator with engineering documentation and analysis regarding the proposed change. If the change to the base flood elevation or boundaries of the special flood hazard area 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.

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. (Res. 2020-63 (Att. A) (part), 6/9/20).

Article VI. Enforcement, Variances and Penalties

3.20.340 Violations and fines.

It is unlawful for a person, firm, or corporation to erect, construct, enlarge, alter, repair, move, improve, remove, convert, equip, use, occupy, or maintain any building, structure, or activity or cause or permit the same to be done, in violation of this chapter. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.350 Action to restrain violations.

Whenever any development is being undertaken contrary to the provisions of this chapter, the floodplain administrator shall order the work stopped on the development by serving notice in writing on any persons engaged in or causing such work to be done; and any such person shall stop such work until authorized by the floodplain administrator to proceed. If the violation still continues or is still in effect, the matter shall be referred to the Chelan County code enforcement officer, hearing examiner, and/or prosecuting attorney who shall commence action to restrain and enjoin further activities in violation of this chapter. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.360 Permits prohibited.

No building permit, septic tank permit, or land use permit shall be issued, nor shall service from the Chelan County Public Utility District No. 1 be connected, to any development or activity in violation of this chapter. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.370 Penalties.

Any person, firm or corporation violating any provisions of this chapter shall be subject to enforcement action and penalties pursuant to the enforcement and violation provisions of the Chelan County Code. (Res. 2020-63 (Att. A) (part), 6/9/20).

3.20.380 Variance procedure.

The hearing examiner is authorized to grant variances from the requirements of this chapter subject to the following general and specific requirements. The hearing examiner may attach such conditions to the granting of variances as deemed necessary to further the purposes of this chapter.

(1) General Requirements.

(A) No variance shall be granted unless it can be shown that all of the following conditions exist:

(i) The plight of the applicant is due to unique physical characteristics such as topography, lot size or shape, over which the applicant has no control.

(ii) The hardship asserted by the applicant is not the result of the applicant’s or the owner’s action.

(iii) The authorization of the variance shall not be materially detrimental to the public welfare and safety, to the purposes of this chapter, be injurious to the property in the same district or neighborhood in which the property is located, or be otherwise detrimental to the objectives of the comprehensive plan.

(iv) The hardship asserted by the applicant results from the application of this chapter to the property.

(2) Specific Requirements.

(A) In considering variance applications, the hearing examiner shall consider all technical evaluations, all relevant factors, all standards specified in other sections of this chapter, and

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

(ii) The danger to life and property due to flooding or erosion damage;

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

(iv) The importance of the services provided by the proposed facility to the community;

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

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

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

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

(ix) The safety of access to the property in times of flood for ordinary and emergency vehicles;

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

(xi) The costs of providing government services during and after flood conditions, including maintenance and repair of public utilities and facilities such as sewer, gas, electrical, and water systems, and streets and bridges.

(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:

(i) Upon 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;

(ii) 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;

(iii) Upon a determination that the variance is the minimum necessary, considering the flood hazard, to afford relief;

(iv) Upon a showing of good and sufficient cause;

(v) Upon a determination that failure to grant the variance would result in exceptional hardship to the applicant;

(vi) 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 Section 3.20.100 in the definition of “functionally dependent use”;

(vii) Upon 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) 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 base flood elevation, provided the procedures of Articles III and IV of this chapter have been fully considered. As the lot size increases beyond one-half acre, the technical justification required for issuing the variance increases.

(3) Additional Requirements for the Issuance of a Variance.

(A) Any applicant to whom a variance is granted shall be given written notice over the signature of a community official that:

(i) The issuance of a variance to construct a structure below the base flood elevation will result in increased premium rates for flood insurance up to amounts as high as twenty-five dollars for one hundred dollars of insurance coverage; and

(ii) Such construction below the base flood elevation increases risks to life and property.

(B) The floodplain administrator shall maintain a record of all variance actions, including justification for their issuance.

(C) The floodplain administrator shall condition the variance as needed to ensure that the requirements and criteria of this chapter are met.

(D) 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 the flood elevations should be quite rare. (Res. 2020-63 (Att. A) (part), 6/9/20).