A. Applicability: All permit applications will be reviewed to determine whether proposed building sites will be reasonably safe from flooding. If a proposed building site is in a flood prone area, all new construction and substantial improvements shall: 1) be designed (or modified) and adequately anchored to prevent flotation, collapse, or lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy, 2) be constructed with materials resistant to flood damage, 3) be constructed by methods and practices that minimize flood damages, and 4) be constructed with electrical, heating, ventilation, plumbing, and air conditioning equipment and other service facilities that are designed and/or located so as to prevent water from entering or accumulating within the components during conditions of flooding.
This section's protection requirement applies to all new structures and substantial improvements, which include:
1. Construction or placement of a new structure.
2. Reconstruction, rehabilitation, or other improvement that will result in a substantially improved building.
3. Repairs to an existing building that has been substantially damaged.
4. Placing a manufactured home on a site.
5. Placing a recreational vehicle or travel trailer on a site for more than one hundred eighty (180) days.
B. Flood Protection Standards:
1. All new structures and substantial improvements shall have the lowest floor, including basement, elevated above the FPE.
2. The structure shall be aligned parallel with the direction of flood flows where practicable.
3. The structure shall be anchored to prevent flotation, collapse, or lateral movement of the structure.
4. The structure shall be aligned parallel with the direction of flood flows where practicable.
5. The structure shall be anchored to prevent flotation, collapse, or lateral movement of the structure.
6. All materials below the FPE shall be resistant to flood damage and firmly anchored to prevent flotation.
7. Materials harmful to aquatic wildlife, such as creosote, are prohibited below the FPE.
8. Electrical, heating, ventilation, ductwork, plumbing, and air conditioning equipment and other service facilities shall be elevated above the FPE. Water, sewage, electrical, and other utility lines below the FPE shall be constructed so as to prevent water from entering or accumulating within them during conditions of flooding.
9. Fully enclosed areas below the lowest floor that are subject to flooding shall be used only for parking, storage, or building access and shall be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of floodwaters. Designs for meeting this requirement shall either be certified by a registered professional engineer or licensed architect and/or meet or exceed the following minimum criteria:
a. A minimum of two (2) openings having a total net area of not less than one square inch for every square foot of enclosed area subject to flooding shall be provided.
b. The bottom of all openings shall be no higher than one foot (1') above grade.
c. Openings may be equipped with screens, louvers, or other coverings or devices provided that they permit the automatic entry and exit of floodwaters.
C. Nonresidential Construction: New construction and substantial improvement of any commercial, industrial or other nonresidential structure shall be elevated in accordance with this chapter. As an alternative to elevation, a new or substantial improvement to a nonresidential structure and its attendant utility and sanitary facilities, may be dry floodproofed in A zones. The project must meet the following:
1. The structure is not located in zones V, V1-30, or VE; and
2. Below the FPE the structure is watertight with walls substantially impermeable to the passage of water; and
3. The structural components are capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy; and
4. The plans are certified by a registered professional engineer or licensed architect that the design and methods of construction are in accordance with accepted standards of practice for meeting provisions of this subsection based on their development and/or review of the structural design, specifications and plans. Such certifications shall be provided to the floodplain administrator as set forth in this chapter.
D. Manufactured Homes: All manufactured homes to be placed or substantially improved on sites shall be:
1. Elevated on a permanent foundation in accordance with this chapter, and
2. Securely anchored to an adequately anchored foundation system to resist flotation, collapse and lateral movement. Methods of anchoring may include, but are not to be limited to, use of over the top or frame ties to ground anchors. This requirement is in addition to other applicable anchoring requirements for resisting wind forces. (For more detailed information, see the "FEMA Guidebook" p-85.)
E. Recreational Vehicles: Recreational vehicles placed on sites shall:
1. Be on the site for fewer than one hundred eighty (180) consecutive days, or
2. Be fully licensed and ready for highway use, on their wheels or jacking system, attached to the site only by quick disconnect type utilities and security devices, and have no permanently attached additions.
F. Appurtenant Structures: A structure which is on the same parcel of property as the principal structure and the use of which is incidental to the use of the principal structure and is not used for human habitation may be exempt from the elevation requirement of this chapter, provided:
1. It is used only for parking or storage;
2. It is constructed and placed on the building site so as to offer minimum resistance to the flow of floodwaters;
3. It is anchored to prevent flotation which may result in damage to other structures;
4. All portions of the structure below the FPE must be constructed of flood resistant materials;
5. Service utilities such as electrical and heating equipment meet the standards of this chapter;
6. It has openings to allow free flowage of water that meet the criteria in this chapter;
7. The project meets all the other requirements of this chapter.
G. Utilities:
1. All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of floodwaters into the systems;
2. Water wells shall be located outside the floodway and shall be protected to the FPE;
3. New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of floodwaters into the systems and discharges from the systems into floodwaters;
4. New on site waste disposal systems are prohibited in the city.
H. Subdivision Proposals:
1. All subdivision proposals shall be consistent with the need to minimize flood damage;
2. All subdivision proposals shall have public utilities and facilities, such as sewer, gas, electrical, and water systems located and constructed to minimize or eliminate flood damage;
3. All subdivision proposals shall have adequate drainage provided to reduce exposure to flood damage;
4. Where base flood elevation data has not been provided or is not available from another authorized source, it shall be generated for subdivision proposals and other proposed developments which contain at least fifty (50) lots or five (5) acres (whichever is less). (Ord. 2017-1009, 3-1-2017)