14.270.070 General Standards for Flood Hazard Reduction.
In all areas of special flood hazards, the following standards are required:
A. Anchoring (44 CFR 60.3(a) and (b)).
1. All new construction and substantial improvements, including those related to manufactured homes, shall be anchored to prevent flotation, collapse, or lateral movement of the structure resulting from hydrodynamic and hydrostatic loads including the effects of buoyancy (44 CFR 60.3(a)(3)(i)).
2. All manufactured homes shall be anchored to prevent flotation, collapse, or lateral movement, and shall be installed using methods and practices that minimize flood damage. Anchoring methods may include, but are not limited to, use of over-the-top or frame ties to ground anchors (44 CFR 60.3(b)(8)). For more detailed information, refer to guidebook, FEMA-85, “Manufactured Home Installation in Flood Hazard Areas.”
B. Construction Materials and Methods (44 CFR 60.3(a)(3)(ii) – (iv)).
1. All new construction and substantial improvements shall be constructed with materials and utility equipment resistant to flood damage.
2. All new construction and substantial improvements shall be constructed using methods and practices that minimize flood damage.
3. Electrical, heating, ventilation, plumbing, and air-conditioning equipment and other service facilities shall be designed and/or otherwise elevated or located so as to prevent water from entering or accumulating within the components during conditions of flooding.
C. Storage of Materials and Equipment.
1. The storage or processing of materials that could be injurious to human, animal, or plant life if released due to damage from flooding is prohibited in special flood hazard areas.
2. Storage of other material or equipment may be allowed if not subject to damage by floods and if firmly anchored to prevent flotation, or if readily removable from the area within the time available after flood warning.
D. Utilities (44 CFR 60.3(a)(5) and (6)).
1. All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of flood waters into the systems;
2. Water wells shall be located on high ground that is not in the floodway (WAC 173-160-171);
3. New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of flood waters into the systems and discharges from the systems into flood waters;
4. On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.
E. Subdivision and Development Proposals (44 CFR 60.3(a)(4) and (b)(3)). All subdivisions, including manufactured home parks, as well as any new development or redevelopment shall:
1. Be consistent with the need to minimize flood damage;
2. Have public utilities and facilities, such as sewer, gas, electrical, and water systems, located and constructed to minimize or eliminate flood damage;
3. Have adequate drainage provided to reduce exposure to flood damage;
4. Where subdivision proposals and other proposed developments contain greater than fifty (50) lots or five (5) acres (whichever is the lesser) base flood elevation data shall be included as part of the application. (Ord. 2400, 2020)