In all areas of special flood hazards the following provisions are required for all new construction and substantial improvements:
(1) 
All new construction or substantial improvements shall 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) 
All new construction or substantial improvements shall be constructed by methods and practices that minimize flood damage;
(3) 
All new construction or substantial improvements shall be constructed with materials and utility resistant to flood damage;
(4) 
All new construction or substantial improvements shall 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;
(5) 
All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of flood waters into the system;
(6) 
New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of flood waters into the system and discharge from the systems into flood waters, and,
(7) 
On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.
(8) 
New construction and substantial improvements, when located in multiple flood zones with varying base flood elevations or in the same flood zone with multiple base flood elevations must meet the requirements for the flood zone with the most stringent requirements and the highest base flood elevation.
(Ordinance 2023-24, § II, adopted 7/5/2023)
In all areas of moderate or special flood hazards where base flood elevation data has been provided as set forth in (i) article III, section (b), (ii) article 4, section (b)(8), or (iii) article V, section (c)(3), the following provisions are required:
(1) 
Residential construction.
a. 
Within an area of special flood hazard, new construction and substantial improvement of any residential structure shall have the lowest floor, including basement, and all components of the mechanical, electrical, and plumbing system and any other service facility elevated to at least 18 inches above the base flood elevation or 24 inches above the top of the curb, whichever is higher.
b. 
Within a moderate flood hazard area, new construction and substantial improvement of any residential structure shall have the lowest floor, including basement, and all components of the mechanical, electrical, and plumbing systems and any other facility elevated to at least 12 inches above the base flood elevation or 18 inches above the top of the curb, whichever is higher.
(2) 
Nonresidential construction.
New construction and substantial improvements of any commercial, industrial or other nonresidential structure shall either have the lowest floor (including basement) elevated to 18 inches above the base flood elevation or together with attendant utility and sanitary facilities, be designed so that below the base flood level the structure is watertight with walls substantially impermeable to the passage of water and with structural components having the capability of resisting hydrostatic and hydrodynamic loads and the effects of buoyancy. A registered professional engineer or architect shall develop and/or review structural design, specifications, and plans for the construction, and shall certify that the design and methods of construction are in accordance with accepted standards of practice as outlined in this subsection. A record of such certification which includes the specific elevation (in relation to mean sea level) to which such structures are floodproofed shall be maintained by the floodplain administrator.
(3) 
Critical facilities.
New construction and substantial improvement of any critical facilities shall have the lowest floor (including basement and all essential plumbing and utilities, including duct work), elevated or floodproofed to a minimum of 24 inches above the base flood elevation.
(4) 
Enclosures.
New construction and substantial improvements, with fully enclosed areas below the lowest floor that are usable solely for parking of vehicles, building access or storage in an area other than a basement and which are subject to flooding 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 must either be certified by a registered professional engineer or architect or meet or exceed the following minimum criteria:
a. 
A minimum of two openings on separate walls having a total net area of not less than one square-inch for every square foot of enclosed area subject to flooding shall be provided.
b. 
The bottom of all openings shall be no higher than one foot above grade.
c. 
Openings may be equipped with screens, louvers, valves, or other coverings or devices provided that they permit the automatic entry and exit of floodwaters.
(5) 
Manufactured homes.
a. 
Require that all manufactured homes to be placed within Zone A on a community's FHBM or FIRM shall be installed using methods and practices which minimize flood damage. For the purposes of this requirement, manufactured homes must be elevated and anchored to resist flotation, collapse, or lateral movement. Methods of anchoring may include, but are not limited to, use of over-the-top or frame ties to ground anchors. This requirement is in addition to applicable state and local anchoring requirements for resisting wind forces.
b. 
Require that manufactured homes that are placed or substantially improved within Zones A1-30, AH, and AE on the community's FIRM on sites (i) outside of a manufactured home park or subdivision, (ii) in a new manufactured home park or subdivision, (iii) in an expansion to an existing manufactured home park or subdivision, or (iv) in an existing manufactured home park or subdivision on which a manufactured home has incurred "substantial damage" as a result of a flood, be elevated on a permanent foundation such that the lowest floor of the manufactured home is elevated to or above the base flood elevation and be securely anchored to an adequately anchored foundation system to resist flotation, collapse, and lateral movement.
c. 
Require that manufactured homes be placed or substantially improved on sites in an existing manufactured home park or subdivision with Zones A1-30, AH and AE on the community's FIRM that are not subject to the provisions of paragraph (4) of this section be elevated so that either:
1. 
The lowest floor of the manufactured home is at or above the base flood elevation, or
2. 
The manufactured home chassis is supported by reinforced piers or other foundation elements of at least equivalent strength that are no less than 36 inches in height above grade and be securely anchored to an adequately anchored foundation system to resist flotation, collapse, and lateral movement.
(6) 
Recreational vehicles.
Require that recreational vehicles placed on sites within Zones A1-30, AH, and AE on the community's FIRM either (i) be on the site for fewer than 180 consecutive days, or (ii) be fully licensed and ready for highway use, or (iii) elevated and anchored to resist flotation, collapse, or lateral movement. Methods of anchoring may include, but are not limited to, use of over-the-top or frame ties to ground anchors. This requirement is in addition to applicable state and local anchoring requirements for resisting wind forces. A recreational vehicle is ready for highway use if it is on its wheels or jacking system, is attached to the site only by quick disconnect type utilities and security devices, and has no permanently attached additions.
(7) 
Prohibited uses.
The following uses are prohibited within a designated floodplain:
a. 
Storage or processing of materials that are hazardous, flammable, or explosive in the identified special flood hazard area.
b. 
Storage of material or equipment that, in times of flooding, could become buoyant and pose an obstruction to flow in identified floodway areas.
(Ordinance 2023-24, § II, adopted 7/5/2023)
(a) 
All subdivision proposals including the placement of manufactured home parks and subdivisions shall be consistent with article I, sections (b), (c), and (d) of this chapter.
(b) 
All proposals for the development of subdivisions including the placement of manufactured home parks and subdivisions shall meet floodplain development permit requirements of article III, section (c); article IV, section (c); and the provisions of article V of this chapter.
(c) 
Base flood elevation data shall be provided for subdivision proposals and other proposed development including the placement of manufactured home parks and subdivisions which is greater than 50 lots or five acres, whichever is lesser, if not otherwise provided pursuant to article III, section (b) or article 4, section (b)(8) of this article.
(d) 
All subdivision proposals including the placement of manufactured home parks and subdivisions shall have adequate drainage provided to reduce exposure to flood hazards.
(e) 
All subdivision proposals including the placement of manufactured home parks and subdivisions shall have public utilities and facilities such as sewer, gas, electrical and water systems located and constructed to minimize or eliminate flood damage.
(Ordinance 2023-24, § II, adopted 7/5/2023)
Located within the areas of special flood hazard established in section 105-22 are areas designated as shallow flooding. These areas have special flood hazards associated with flood depths of one to three feet where a clearly defined channel does not exist, where the path of flooding is unpredictable, and where velocity flow may be evident. Such flooding is characterized by ponding or sheet flow; therefore, the following provisions apply:
(1) 
All new construction and substantial improvements of residential structures, including manufactured homes, have the lowest floor (including basement) elevated 18 inches above the base flood elevation or the highest adjacent grade at least as high as the depth number specified in feet on the community's FIRM or base level engineering assessment (at least 24 inches if no depth number is specified).
(2) 
All new construction and substantial improvements of non-residential structures;
a. 
Have the lowest floor (including basement) elevated to or above the base flood elevation or the highest adjacent grade at least as high as the depth number specified in feet or inches on the community's FIRM or base level engineering assessment (at least 24 inches if no depth number is specified), or
b. 
Together with attendant utility and sanitary facilities be designed so that below the base specified flood depth in an AO Zone, or below the base flood elevation in an AH Zone, or estimated flood depth in a base level engineering assessment, level the structure is watertight with walls substantially impermeable to the passage of water and with structural components having the capability of resisting hydrostatic and hydrodynamic loads of effects of buoyancy.
(3) 
A registered professional engineer or architect shall submit a certification to the floodplain administrator that the standards of this section, as proposed in article IV, section (c) are satisfied.
(4) 
Require within Zones AH or AO adequate drainage paths around structures on slopes, to guide flood waters around and away from proposed structures.
(Ordinance 2023-24, § II, adopted 7/5/2023)
Floodways—Located within areas of special flood hazard established in article III, section (b), are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of flood waters which carry debris, potential projectiles and erosion potential, the following provisions shall apply:
(1) 
Encroachments are prohibited, including fill, new construction, substantial improvements and other development within the adopted regulatory floodway unless it has been demonstrated through hydrologic and hydraulic analyses performed in accordance with standard engineering practice and certification by a registered professional engineer is provided demonstrating that the proposed encroachment would not result in any increase in flood levels within the community during the occurrence of the base flood discharge.
(2) 
If article V, section (e)(1) above is satisfied, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of article V.
(3) 
Under the provisions of 44 CFR Chapter 1, Section 65.12, of the National Flood Insurance Program Regulations, a community may permit encroachments within the adopted regulatory floodway that would result in an increase in base flood elevations, provided that the community first completes all of the provisions required by section 65.12.
(Ordinance 2023-24, § II, adopted 7/5/2023)
If any section, clause, sentence, or phrase of this chapter is held to be invalid or unconstitutional by any court of competent jurisdiction, then said holding shall in no way affect the validity of the remaining portions of this chapter.
(Ordinance 2023-24, § II, adopted 7/5/2023)
No structure or land shall hereafter be constructed, located, extended, converted, or altered without full compliance with the terms of this chapter and other applicable regulations. Violation of the provisions of this chapter by failure to comply with any of its requirements (including violations of conditions and safeguards established in connection with conditions) shall constitute a misdemeanor. Any person who violates this chapter or fails to comply with any of its requirements shall upon conviction thereof be fined not more than $500.00 for each violation, and in addition shall pay all costs and expenses involved in the case. Nothing herein contained shall prevent the city from taking such other lawful action as is necessary to prevent or remedy any violation.
(Ordinance 2023-24, § II, adopted 7/5/2023)
Upon notice from the floodplain administrator that work on any building, structure, dike, bridge or any improvement which would affect water drainage is being done contrary to the provisions of this chapter, or in a dangerous or unsafe manner, such work shall be immediately stopped. Such notice shall be in writing and shall be given to the owner of the property or to his agent, or to the person doing the work, and shall state the conditions under which work may be resumed. Where an emergency exists, no written notice shall be required to be given by the floodplain administrator; provided however, written notice shall follow within 24 hours from the time oral notice to stop was issued.
(Ordinance 2023-24, § II, adopted 7/5/2023)
A building (home or business), if insured through the National Flood Insurance Program, is eligible for an ICC payment when the city's floodplain administrator determines that the building is repetitively damaged as a result of floods within a 10-year period (see repetitive loss definition). To make this determination, there must be two claims filed in a 10-year period and the claims' average must equal or exceed 25% of the building's market value.
(Ordinance 2025-35 adopted 6/18/2025)