Division 3. Environment
Chapter 18.19
FLOOD DAMAGE PREVENTION
Sections:
18.19.010 Authorization, findings of fact, purpose, and objectives.
18.19.040 Provisions for flood hazard reduction.
18.19.010 Authorization, findings of fact, purpose, and objectives.
A. Statutory Authorization. The Legislature of the State of Washington has delegated the responsibility to local communities to adopt floodplain management regulations designed to promote the public health, safety, and general welfare of its citizenry. Therefore, the city council of the city of Yelm does ordain as follows:
B. Findings of Fact. The flood hazard areas of the city of Yelm are subject to periodic inundation, which may result 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.
These flood losses may be caused by the cumulative effect of obstructions in areas of special flood hazards that 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.
C. Statement of Purpose. It is the purpose of this chapter to promote the public health, safety, and general welfare; reduce the annual cost of flood insurance; and minimize public and private losses due to flood conditions in specific areas by provisions designed to:
1. Protect human life and health;
2. Minimize expenditure of public money for costly flood control projects;
3. Minimize the need for rescue and relief efforts associated with flooding and generally 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 blight areas caused by flooding;
7. Notify potential buyers that the property is in a special flood hazard area;
8. Notify those who occupy flood hazard areas that they assume responsibility for their actions; and
9. Participate in and maintain eligibility for flood insurance and disaster relief.
D. Methods of Reducing Flood Losses. In order to accomplish its purposes, this chapter includes methods and provisions for:
1. Restricting or prohibiting development that is dangerous to health, safety, and property due to water or erosion hazards, or which result in damaging increases in erosion or in flood heights or velocities;
2. Requiring that development vulnerable to floods be protected against flood damage at the time of initial construction;
3. Controlling the alteration of natural floodplains, stream channels, and natural protective barriers, which help accommodate or channel flood waters;
4. Controlling filling, grading, dredging, and other development, which may increase flood damage; and
5. Preventing or regulating the construction of flood barriers that unnaturally divert floodwaters or may increase flood hazards in other areas. (Ord. 1107 § 1, 2023).
18.19.020 General provisions.
A. Lands to Which This Chapter Applies. This chapter shall apply to all special flood hazard areas within the boundaries of the city of Yelm.
B. Basis for Establishing the Areas of Special Flood Hazard. The special flood hazard areas identified by the Federal Insurance Administrator in a scientific and engineering report entitled “The Flood Insurance Study (FIS) for Thurston County, WA and Incorporated Areas” dated October 19, 2023, and any revisions thereto, with accompanying flood insurance rate maps (FIRMs) dated October 19, 2023, and any revisions thereto, are hereby adopted by reference and declared to be a part of this chapter. The FIS and the FIRM are on file with the city clerk. The best available information for flood hazard area identification as outlined in YMC 18.19.030(C)(2) shall be the basis for regulation until a new FIRM is issued that incorporates data utilized under YMC 18.19.030(C)(2).
C. Compliance. All development within special flood hazard areas is subject to the terms of this chapter and other applicable regulations.
D. 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. Violations 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 punished by imprisonment in jail for a term of up to 90 days, or by a fine of up to $1,000, or both, and in addition shall pay all costs and expenses involved in the case. Nothing herein contained shall prevent the city of Yelm from taking such other lawful action as is necessary to prevent or remedy any violation.
E. 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.
F. Severability. This chapter and the various parts thereof are hereby declared to be severable. Should any provision 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 provision so declared to be unconstitutional or invalid. (Ord. 1107 § 1, 2023).
18.19.030 Administration.
A. Establishment of Land Use Application.
1. Land Use Application Required. A completed land use application shall be submitted and all applicable permits shall be obtained before construction or development begins within any area of special flood hazard established in YMC 18.19.020(B). The permit shall be for all structures including manufactured homes, as set forth in Chapter 18.02 YMC, Definitions, and for all development including fill and other activities, also as set forth in Chapter 18.02 YMC.
2. Land Use Application. An application for land use shall be made on forms furnished by the city 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. Where development is proposed in or adjacent to a special flood hazard area, the following additional information is required:
a. 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;
b. Elevation in relation to mean sea level to which any structure has been floodproofed;
c. 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 YMC 18.19.040(B)(2);
d. Description of the extent to which a watercourse will be altered or relocated as a result of proposed development;
e. Where development is proposed in a floodway, an engineering analysis indication no rise of the base flood elevation; and
f. Any other such information that may be reasonably required by the floodplain administrator in order to review the application.
B. Designation of the Floodplain Administrator. The city engineer is hereby appointed to administer, implement, and enforce this chapter by granting or denying land use permits in accordance with its provisions. The floodplain administrator may delegate authority to implement these provisions.
C. Duties and Responsibilities of the Floodplain Administrator. Duties of the floodplain administrator shall include, but not be limited to:
1. Permit Review. Review all land use permits to determine that:
a. The permit requirements of this chapter have been satisfied;
b. All other required state and federal permits have been obtained;
c. The site is reasonably safe from flooding;
d. The proposed development is not located in the floodway. If located in the floodway, ensure that the encroachment provisions of YMC 18.19.040(D)(1) are met;
e. Notify FEMA when annexations occur in the special flood hazard area.
2. Use of Other Base Flood Data (In A Zones). When base flood elevation data has not been provided (in A zones) in accordance with YMC 18.19.020(B), Basis for Establishing the Areas of Special Flood Hazard, the floodplain administrator shall obtain, review, and reasonably utilize any base flood elevation and floodway data available from a federal, state, or other source, in order to administer YMC 18.19.040(B), Specific Standards, and YMC 18.19.040(D), Floodways.
3. Information to Be Obtained and Maintained.
a. Where base flood elevation data is provided through the FIS, FIRM, or required as in subsection (C)(2) of this section, obtain and maintain a record of 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.
b. 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 (C)(2) of this section:
i. Obtain and maintain a record of the elevation (in relation to mean sea level) to which the structure was floodproofed.
ii. Maintain the floodproofing certifications required in subsection (A)(2)(c) of this section.
4. Certification required by YMC 18.19.040(D)(1).
5. Records of all variance actions, including justification for their issuance.
6. Improvement and damage calculations.
7. Maintain for public inspection all records pertaining to the provisions of this chapter.
D. Alteration of Watercourse. Whenever a watercourse is to be altered or relocated:
1. Notify adjacent communities and the Department of Ecology prior to such alteration or relocation of a watercourse, and submit evidence of such notification to the Federal Insurance Administrator through appropriate notification means.
2. Assure that the flood carrying capacity of the altered or relocated portion of said watercourse is maintained.
E. Review of Building Permits. Where elevation data is not available either through the FIS, FIRM, or from another authoritative source (subsection (C)(2) 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.
F. Changes to Special Flood Hazard Area. 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 conditional letter of map change and/or a letter of map change, then the project approval shall be conditioned accordingly. (Ord. 1107 § 1, 2023).
18.19.040 Provisions for flood hazard reduction.
A. General Standards. In all areas of special flood hazards, the following standards are required:
1. Anchoring.
a. 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.
b. 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.”
2. Construction Materials and Methods.
a. All new construction and substantial improvements shall be constructed with materials and utility equipment resistant to flood damage.
b. All new construction and substantial improvements shall be constructed using methods and practices that minimize flood damage.
c. 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.
3. Storage of Materials and Equipment.
a. 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.
b. 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.
4. Utilities.
a. All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of flood waters into the systems;
b. Water wells shall be located on high ground that is not in the floodway (WAC 173-160-171);
c. New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of flood waters into the systems and discharges from the systems into flood waters;
d. On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.
5. Development and Subdivision Proposals. All development, including subdivisions, shall:
a. Be consistent with the need to minimize flood damage;
b. Have public utilities and facilities, such as sewer, gas, electrical, and water systems located and constructed to minimize or eliminate flood damage;
c. Have adequate drainage provided to reduce exposure to flood damage;
d. Where subdivision proposals and other proposed developments contain greater than 50 lots or five acres (whichever is the lesser) base flood elevation data shall be included as part of the application.
B. Specific Standards. In all areas of special flood hazards where base flood elevation data has been provided as set forth in YMC 18.19.020(B), Basis for Establishing the Areas of Special Flood Hazard, or YMC 18.19.030(C)(2), Use of Other Base Flood Data, the following provisions are required:
1. Residential Construction.
a. In AE 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 least one foot above the BFE.
b. New construction and substantial improvement of any residential structure in an A zone for which a BFE 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 two feet above the highest adjacent grade.
c. Fully enclosed areas below the lowest floor that are subject to flooding are prohibited, or shall be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of floodwaters. Designs must meet or exceed the following minimum criteria:
i. Have a minimum of two openings with a total net area of not less than one square inch for every square foot of enclosed area subject to flooding.
ii. The bottom of all openings shall be no higher than one foot above grade.
iii. Openings may be equipped with screens, louvers, valves, or other coverings or devices; provided, that they permit the automatic entry and exit of floodwater.
iv. A garage attached to a residential structure, constructed with the garage floor slab below the BFE, must be designed to allow for the automatic entry and exit of flood waters.
Alternatively, a registered engineer or architect may design and certify engineered openings.
2. Nonresidential Construction. New construction and substantial improvement of any commercial, industrial or other nonresidential structure shall meet the requirements of subsections (B)(2)(a) or (b) of this section.
a. New construction and substantial improvement of any commercial, industrial or other nonresidential structure shall meet all of the following requirements:
i. In AE zones or other A zoned areas where the BFE has been determined or can be reasonably obtained, new construction and substantial improvement of any commercial, industrial, or other nonresidential structure shall have the lowest floor, including basement, elevated one foot or more above the BFE, or elevated as required by ASCE 24, whichever is greater. Mechanical equipment and utilities shall be waterproofed or elevated least one foot above the BFE, or as required by ASCE 24, whichever is greater.
ii. If located in an A zone for which a BFE is not available and cannot be reasonably obtained, the structure shall be reasonably safe from flooding, but in all cases the lowest floor shall be at least two feet above the highest adjacent grade.
iii. Fully enclosed areas below the lowest floor that are subject to flooding are prohibited, or shall meet the requirements of YMC 18.19.030(C)(3)(b).
b. If the requirements of subsection (B)(2)(a) of this section are not met, then new construction and substantial improvement of any commercial, industrial or other nonresidential structure shall meet all of the following requirements:
i. Be dry floodproofed so that below one foot or more above the base flood level the structure is watertight with walls substantially impermeable to the passage of water or dry floodproofed to the elevation required by ASCE 24, whichever is greater;
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 provisions of this subsection (B)(2)(b) based on their development and/or review of the structural design, specifications and plans. Such certifications shall be provided to the floodplain administrator as set forth in YMC 18.19.030(C)(1)(c).
3. Manufactured Homes.
a. All manufactured homes to be placed or substantially improved on sites shall be elevated on a permanent foundation such that the lowest floor of the manufactured home and nonfloodproofed utilities serving the manufactured home are elevated one foot or more above the base flood elevation and be securely anchored to an adequately anchored foundation system to resist flotation, collapse and lateral movement.
b. Manufactured homes to be placed or substantially improved on sites in an existing manufactured home park or subdivision that are not subject to the above manufactured home provisions shall be elevated so that either:
i. The lowest floor of the manufactured home is elevated one foot or more above the base flood elevation; or
ii. 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 are securely anchored to an adequately anchored foundation system to resist flotation, collapse, and lateral movement.
4. Recreational Vehicles. Recreational vehicles placed on sites are required to either:
a. Be on the site for fewer than 180 consecutive days; or
b. Be fully licensed and ready for highway use, on wheels or jacking system, attached to the site only by quick disconnect type utilities and security devices, and have no permanently attached additions; or
c. Meet the requirements of subsection (B)(3) of this section.
5. 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.
6. Detached Accessory Structures (Detached Garages and Small Storage Structures).
a. Detached accessory 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:
i. In special flood hazard areas, the structure is not larger than a one-story two-car garage;
ii. The portions of the structure located below the BFE must be built using flood resistant materials;
iii. The structure must be adequately anchored to prevent flotation, collapse, and lateral movement;
iv. Any machinery or equipment servicing the structure must be elevated or floodproofed to or above the BFE;
v. The structure must comply with floodway encroachment provisions in subsection (D)(1) of this section;
vi. The structure must be designed to allow for the automatic entry and exit of floodwaters in accordance with subsection (B)(1) 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 appurtenant structures not meeting the above standards must be constructed in accordance with all applicable standards in subsection (B)(1) 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.
7. Agricultural Structures Damaged by Flooding. Agricultural structures that are substantially damaged by flooding and agricultural structures that are repetitive loss structures are permitted to be repaired or restored to predamage condition, provided the following are satisfied:
a. If substantially damaged, the substantial damage determination is based only on the cost to repair damage caused by flooding to predamage conditions.
b. The proposed repair or restoration does not change the size of the structure and does not significantly alter the nature of the building. With the exception of costs associated with wet floodproofing in accordance with subsection (B)(7)(e) of this section, proposals that include work beyond or in addition to that necessary to repair or restore the structure to predamage condition must be regulated as substantial improvements.
c. The repaired or restored structure will continue to be an agricultural structure, as defined in these regulations.
d. Owners are notified, in writing, that agricultural structures approved under this section:
i. Will not be eligible for disaster relief under any program administered by the Federal Emergency Management Agency or any other federal agency.
ii. Will have National Flood Insurance Program flood insurance policies rated based on the structure’s risk.
iii. May be denied National Flood Insurance Program flood insurance policies if repairs do not include the wet floodproofing construction requirements of subsection (B)(7)(e) of this section.
e. Wet Floodproofing Construction Requirements. When owners elect to wet floodproof flood-damaged agricultural structures as part of repair or restoration to predamage condition, the structure shall:
i. Be anchored to resist flotation, collapse, and lateral movement.
ii. Have flood damage-resistant materials below the base flood elevation.
iii. Have mechanical, electrical, and utility equipment elevated or floodproofed to or above the BFE.
iv. In special flood hazard areas, have flood openings in compliance with the requirements of subsection (B)(1) of this section.
C. AE Zone With Base Flood Elevations But No Floodways. In areas with BFEs (but a regulatory floodway has not been designated), no new construction, substantial improvements, or other development (including fill) shall be permitted within zone AE on the FIRM, 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.
D. Floodways. Located within areas of special flood hazard established in YMC 18.19.020(B) 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 50 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 in the 50 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 90 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 one foot higher than the BFE;
vii. New and replacement water supply systems are designed to eliminate or minimize infiltration of flood waters into the system;
viii. 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; 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 of Ecology 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 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.
3. All Other Building Standards Apply in the Floodway. If subsection (D)(1) of this section is satisfied or construction is allowed pursuant to subsection (D)(2) of this section, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of this section.
E. General Requirements for Other Development. All development, including manmade changes to improved or unimproved real estate for which specific provisions are not specified in this ordinance or the state building codes with adopted amendments and any city of Yelm amendments, shall:
1. Be located and constructed to minimize flood damage;
2. Meet the encroachment limitations of this chapter if located in a regulatory floodway;
3. Be anchored to prevent flotation, collapse, or lateral movement resulting from hydrostatic loads, including the effects of buoyancy, during conditions of the design flood;
4. Be constructed of flood damage-resistant materials;
5. Meet the flood opening requirements of subsection (B)(1) of this section; and
6. Have mechanical, plumbing, and electrical systems above the design flood elevation or meet the requirements of ASCE 24, except that minimum electric service required to address life safety and electric code requirements is permitted below the design flood elevation, provided it conforms to the provisions of the electrical part of building code for wet locations. (Ord. 1107 § 1, 2023).
18.19.050 Variances.
Variances from the floodplain management standards shall only be issued if meeting all of the applicable criteria in subsections A and B of this section. 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.
A. Requirements for Variances.
1. General Variances Criteria.
a. Variances shall not be issued within any floodway if any increase in flood levels during the base flood discharge would result;
b. Upon a determination that the variance is the minimum necessary, considering the flood hazard, to afford relief;
c. Upon a showing of good and sufficient cause;
d. Upon a determination that failure to grant the variance would result in exceptional hardship to the applicant;
e. 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 state laws or local ordinances.
2. Special Circumstances.
a. 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 Chapter 18.02 YMC in the definition of “functionally dependent use.” In order to approve a variance for a functionally dependent use, the criteria in subsection (A)(1) of this section must be met.
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. In order to approve a variance for the repair, rehabilitation, or restoration of a historic structure, the criteria in subsection (A)(1) of this section must be met.
c. Accessory Structures and Agricultural Structures. A variance is authorized to be issued for the construction or substantial improvement of accessory structures and agricultural structures, provided the requirements of this section and the following are satisfied:
i. Accessory Structures. A determination that the proposed accessory structure:
(A) Represents minimal investment and has low damage potential (amount of physical damage, contents damage, and loss of function).
(B) Is not larger than the size limits specified in YMC 18.19.040(B)(6).
(C) Complies with the wet floodproofing construction requirements of subsection (A)(2)(c)(iii) of this section.
ii. Agricultural Structures. A determination that the proposed agricultural structure:
(A) Is used exclusively in connection with the production, harvesting, storage, raising, or drying of agricultural commodities and livestock, or storage of tools or equipment used in connection with these purposes or uses, and will be restricted to such exclusive uses.
(B) Has low damage potential (amount of physical damage, contents damage, and loss of function).
(C) Does not increase risks and pose a danger to public health, safety, and welfare if flooded and contents are released, including but not limited to the effects of flooding on manure storage, livestock confinement operations, liquefied natural gas terminals, and production and storage of highly volatile, toxic, or water-reactive materials.
(D) Complies with the wet floodproofing construction requirements of subsection (A)(2)(c)(iii) of this section.
iii. Wet Floodproofing Construction Requirements. Wet floodproofed structures shall:
(A) Be anchored to resist flotation, collapse, and lateral movement.
(B) Have flood damage-resistant materials below the base flood elevation.
(C) Have mechanical, electrical, and utility equipment elevated or floodproofed to or above the BFE.
(D) In special flood hazard areas other than coastal high hazard areas, have flood openings in compliance with YMC 18.19.040(B)(1)(c).
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 YMC 18.19.030 and 18.19.040 have been fully considered. As the lot size increases beyond one-half acre, the technical justification required for issuing the variance increases. In order to approve a variance pursuant to this subsection, the criteria in subsection (A)(1) of this section must be met.
B. Additional Variance Considerations. In considering variance applications, the city of Yelm 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 that are not subject to flooding or erosion damage;
7. The compatibility of the proposed use with existing and anticipated development;
8. The relationship of the proposed use to the comprehensive plan and floodplain management program for that area;
9. The safety of access to the property in time of flood for ordinary and emergency vehicles;
10. The expected heights, velocity, duration, rate of rise, and sediment transport of the floodwaters expected at the site; and
11. The costs of providing governmental services during and after flood conditions, including maintenance and repair of public utilities and facilities, such as sewer, gas, electrical, water system, reclaimed water system, drainage, and streets and bridges.
C. Flood Damage Prevention Appeal.
1. Determination. The hearing examiner shall process an appeal as provided in YMC 18.14.110 considering the criteria below.
2. Criteria. The hearing examiner shall consider all technical evaluations, all relevant factors, standards specified in other sections of this chapter.
a. The danger that materials may be swept onto other lands to the injury of others;
b. The danger to life and property due to flooding or erosion damage;
c. The susceptibility of the proposed facility and its contents to flood damage and the effect of such damage on the individual owner;
d. The importance of the services provided by the proposed facility to the community;
e. The necessity to the facility of a waterfront location, where applicable;
f. The availability of alternative locations for the proposed use which are not subject to flooding or erosion damage;
g. The compatibility of the proposed use with existing and anticipated development;
h. The relationship of the proposed use to the comprehensive plan and floodplain management program for that area;
i. The safety of access to the property in times of flood for ordinary and emergency vehicles;
j. 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
k. The cost of providing governmental services during and after flood conditions, including maintenance and repair of public utilities and facilities such as sewer, gas, electrical, and water systems, and streets and bridges.
3. Upon consideration of the criteria factors of this section and the purposes of this chapter, the hearing examiner may attach such conditions to the granting of variances as it deems necessary to further the purposes of this chapter.
4. The floodplain administrator, as designated in YMC 18.19.030(B), shall maintain the records of all appeal actions and report any variances to the National Flood Insurance Program upon request. (Ord. 1107 § 1, 2023).