In all areas of special flood hazard shown on the FIRM, the standards set forth in this Article shall be required.
(a)
All new construction and substantial improvements shall be anchored to prevent flotation, collapse or lateral movement of the structure.
(b)
All mobilehomes shall meet the anchoring standards of section 7-27-1210(a).
(a)
All new construction and substantial improvements shall be constructed with flood resistant materials as specified in FEMA Technical Bulletin TB 2-93, and utility equipment resistant to flood damage.
(b)
All new construction and substantial improvement shall use methods and practices that minimize flood damage.
(c)
All elements that function as a part of the structure, such as furnace, hot water heater, air conditioner, etc., shall be elevated to or above the base flood elevation or depth number specified on the Flood Insurance Rate Map (FIRM).
(d)
If within Zones AH or AO, so that there are adequate drainage paths around structures on slopes to guide floodwaters around and away from proposed structures.
(Amended by Ord. No. 3212, effective 10-29-98)
(a)
New construction and substantial improvement of any structure shall conform to the CBC and ASCE 24 as referenced herein and shall have the bottom of the lowest floor, including basement, elevated in accordance with the minimum elevation requirements found in Chapter 2 and ASCE 24. Nonresidential structures may meet the optional standards in paragraph (d) of this Section. Prior to issuance of the occupancy permit or certificate, the elevation of the lowest floor, including the basement, shall be certified by a registered civil engineer or land surveyor that the elevation requirements have been met and verified by the County Surveyor. Notification of compliance shall be recorded as set forth in Section 7-27-1105(b).
(b)
New construction and substantial improvement of any structure in Zone AO shall have the bottom of the lowest floor, including basement, elevated to or above the depth number specified on the Flood Insurance Rate Map (FIRM) as measured from the highest adjacent grade. Nonresidential structures may meet the optional standards in paragraph (d) of this Section. Prior to issuing the occupancy permit, compliance with the elevation requirement shall be certified by a registered civil engineer or land surveyor and verified by the County Surveyor. Notification of compliance shall be recorded as set forth in Section 7-27-1105(b).
(c)
If no base flood elevation or depth number is provided on the FIRM (Zone A), any new construction or substantial improvement of any structure shall have the bottom of the lowest floor, including basement, elevated to:
(1)
Said base flood elevation shall be determined by one of the methods in Section 7-27-1100(b); or
(2)
If the Planning and Development Director and Public Works Director determine that it is unreasonable to determine the base flood elevation pursuant to Section 7-27-1100(b) then the Planning and Development Director and Public Works Director may require that any new construction or substantial improvement of any structures defined in ASCE 24 shall have the bottom of the lowest floor, including basement, elevated to: a height of at least two feet above the highest adjacent grade or DFE, whichever is higher, found in Chapter 2 of ASCE 24.
Nonresidential structures may meet the optional standards set forth in paragraph (d) of this section. Prior to issuing the occupancy permit, compliance with the elevation requirement shall be certified by a registered civil engineer or land surveyor, and verified by the County Surveyor. Notification of compliance shall be recorded as set forth in Section 7-27-1105(b).
(d)
Nonresidential structures with the lowest floor (including basement) below the minimum elevation specified in ASCE 24 Chapter 2 and nonresidential portions of mixed-use structures with the lowest floor (including basement) below the minimum elevation specified by Chapter 2 shall be allowed in conformance with the dry floodproofing requirements of ASCE 24 Section 6.2.
The elevation of the lowest floor (including basement) shall be certified by a registered civil engineer or licensed land surveyor, and verified by the community building inspector to be properly elevated. Such certification or verification shall be provided to the County Surveyor at the following stages of development:
(1)
During review of construction drawings, submit a county-approved preliminary elevation certificate prior to building permit issuance.
(2)
During building construction, once the building pad has been developed or the foundation forms have been erected.
(3)
After construction is completed, an elevation certificate will be required prior to the release of the building occupancy permit.
(e)
Flood Openings. All new construction and substantial improvements of structures with fully enclosed areas below the lowest floor (excluding basements) that are usable solely for parking of vehicles, building access or storage, 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 floodwater. Designs for meeting this requirement shall follow the guidelines in FEMA Technical Bulletins TB 1-08 and TB 7-93, and must meet the following minimum criteria:
(1)
For nonengineered openings:
(A)
Have a minimum of two openings on different sides having a total net area of not less than one square inch for every square foot of enclosed area subject to flooding;
(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 flood water; and
(D)
Buildings with more than one enclosed area must have openings on exterior walls for each area to allow flood water to directly enter; or
(2)
Be certified by a registered civil engineer or architect.
(Amended by Ord. No. 3212, effective 10-29-98; amended by Ord. No. 3425, effective 6-9-11; amended by Ord. No. 3436, effective 3-29-12; amended by Ord. No. 3541, effective 10-11-18)
(a)
Certification of the elevation of the lowest floor or floodproofed elevation is required at that point where the footings are set and slab poured. Failure to submit an elevation certification shall be cause to issue a stop-work order for the project. As built plans certifying the elevation of the lowest adjacent grades is also required.
(b)
Except within zones A and AO, the benches that are shown on the FIRM shall be used in calculating the elevation of the lowest floor.
(c)
If fill is used to elevate a structure above the base flood elevation, the permit holder may apply for a Letter of Map Amendment (LOMA), as set forth in section 7-27-1110(b).
(Amended by Ord. No. 3212, effective 10-29-98)
Areas subject to alluvial fan flooding have irregular flow paths that result in erosion of existing channels and the undermining of fill material. Those areas are identified on the Flood Insurance Rate Map (FIRM) as AO Zones with velocities.
(a)
All structures must be securely anchored to minimize the impact of the flood and sediment damage.
(b)
All new construction and substantial improvements must be elevated on pilings, columns, or armoured fill so that the bottom lowest floor beam is elevated at or above the depth number.
(c)
Use of all fill materials must be armoured to protect the material from the velocity of the flood flow.
(d)
All proposals for subdivision development must provide a mitigation plan that identifies the engineering methods used to:
(e)
All mobilehomes shall be prohibited within the identified hazard area except within existing mobilehome parks or subdivisions.
(a)
The storage or processing of materials that are, in time of flooding, buoyant, flammable, explosive, or could be injurious to human, animal, or plant life, is prohibited.
(b)
Storage of other materials or equipment may be allowed if not subject to major damage by floods and firmly anchored to prevent flotation or if readily removable from the area within the time available after flood warning.
(a)
All new and replacement water supply and sanitary sewage systems shall be designed to minimize or eliminate infiltration of flood waters into the system and discharge from systems into flood waters
(b)
On site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.
(a)
All new subdivision proposals and other proposed development, including proposals for manufactured home parks and subdivisions, greater than 50 lots or 5 acres, whichever is the lesser, shall:
(1)
Identify the Special Flood Hazard Areas (SFHA) and Base Flood Elevations (BFE).
(2)
Identify the elevations of lowest floors of all proposed structures and pads on the final plans.
(3)
If the site is filled above the base flood elevation, the following as-built information for each structure shall be certified by a registered civil engineer or licensed land surveyor and provided as part of an application for a Letter of Map Revision based on Fill (LOMR-F) to the Floodplain Administrator:
(b)
All subdivision proposals and other proposed development shall be consistent with the need to minimize flood damage.
(c)
All subdivision proposals and other proposed development shall have public utilities and facilities such as sewer, gas, electrical and water systems located and constructed to minimize flood damage.
(d)
All subdivisions and other proposed development shall provide adequate drainage to reduce exposure to flood hazards.
(Amended by Ord. No. 3425, effective 6-9-11)
(a)
All new mobilehomes and additions to mobilehomes shall be anchored to resist flotation, collapse, or lateral movement by at least one of the following methods:
(1)
By providing an anchoring system designed to withstand horizontal forces of 15 pounds per square foot and uplift forces of 9 pounds per square foot; or
(2)
By the anchoring of the unit’s system, designed to be in compliance to the Department of Housing and Urban Development Mobilehome Construction and Safety Standards: or
(3)
By bolting the frame or undercarriage to a reinforced, permanent foundation such as a retaining wall or storm wall used to set the unit.
As set forth in section 7-27-1105(b), certification meeting the standards above is required of the installer or state agency responsible for regulating the placement, installation, and anchoring of individual mobilehome units.
(b)
The following standards shall be required for mobilehomes not placed in mobilehome parks or subdivisions, new mobilehome parks or subdivisions, expansions to existing mobilehome parks or subdivisions, and repair, reconstruction, or improvements to existing mobilehome parks or subdivisions that equals or exceeds 50 percent of the value of the streets, utilities, and pads before the repair, reconstruction or improvement commences:
(c)
Certification of compliance is required of the developer responsible for the plan or state agency responsible for regulating mobilehome placement.
(d)
Upon the completion of the structure, the elevation of the lowest floor including basement shall be certified by a registered professional engineer or surveyor, and verified by the community building inspector to be properly elevated. Such certification and verification shall be provided to the Floodplain Administrator.
All recreational vehicles placed on sites within Zones A1-30, AH, and AE on the community’s Flood Insurance Rate Map will either:
(a)
Be on the site for fewer than 180 consecutive days, and be fully licensed and ready for highway use a recreational vehicle is ready for highway use if it is on its wheels or jacking system, is attached to the sit only by quick disconnect type utilities and security devices, and has no permanently attached additions, or
(Added by Ord. No. 3212, effective 10-29-98)
Areas designated as floodways are located within areas of special flood hazard established in section 7-27-1020. Since the floodway is an extremely hazardous area due to the flood velocity of floodwaters which carry debris, potential projectiles, and erosion potential, the following provisions apply:
(a)
Prohibit encroachments, including fill, new construction, substantial improvements, and other development, unless certification by a registered civil engineer is provided demonstrating that encroachments shall not result in any increase in flood levels during the occurrence of the base flood discharge.
(b)
Until a regulatory floodway is adopted, no new construction, substantial development, 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 development, will not increase the water surface elevation of the base flood more than 1 foot at any point.
(c)
No mobilehome shall be placed in a floodway, except in an existing mobilehome park or existing mobilehome subdivision.
(d)
The requirements of section 14.7 of the County Zoning Ordinance (Ordinance No. 352 as amended) shall also be applicable at such time that the County Zoning Map is amended to apply F I zoning within the floodway.
(Amended by Ord. No. 3425, effective 6-9-11)