§ 21.06.050. Standards.

A.

General Standards. In all flood hazard areas, the following standards are required:

1.

Anchoring.

a.

All new construction and substantial improvements shall be anchored to prevent flotation, collapse, or lateral movement of the structure.

b.

All manufactured homes must 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.

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.

Utilities.

a.

All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of floodwaters into the system;

b.

New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of floodwaters into the systems and discharge from the systems into floodwaters; and,

c.

On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.

4.

Subdivision Proposals.

a.

All subdivision proposals shall be consistent with the need to minimize flood damage.

b.

All proposed improvements such as water, sewer, natural gas, telephone and electrical facilities shall be located and constructed in a manner which will minimize damage in the event of a flood.

c.

All subdivision proposals shall have adequate drainage provided to reduce exposure to flood damage.

d.

Where base flood elevation data has not been provided or is not available from another authoritative source, it shall be generated for subdivision proposals which contain 50 lots or 5 acres, whichever is less. The floodplain requirements for subdivision plats, detailed in KPB 20.30.280, apply to all subdivision proposals.

e.

It is the responsibility of the subdivider to provide all necessary information regarding flood protection measures at the time the preliminary plat is presented for consideration by the planning commission.

5.

Review of Development Permits. Where elevation data is not available, applications for development permits 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.

B.

Specific Standards. In all flood hazard areas where base flood elevation data has been provided as set forth in KPB 21.06.030(B), the following provisions are required:

1.

Residential Construction.

a.

New construction and substantial improvement of any residential structure shall have the lowest floor, including basement, elevated to or above the base flood elevation.

b.

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 for meeting this requirement must either be certified by a registered professional engineer or architect or must meet or exceed the following minimum criteria:

i.

A minimum of two openings located on separate walls and having a total net area of not less than 1 square inch for every square foot of enclosed space subject to flooding shall be provided.

ii.

The bottom of all openings shall be no higher than 1 foot above grade.

iii.

Openings may be equipped with screens, louvers, or other coverings or devices provided that they permit the automatic entry and exit of floodwaters.

iv.

Enclosed areas below the base flood elevation must be unfinished and usable only for parking, access or storage of materials easily moved during a flood event.

v.

Before a final floodplain development permit is issued by the planning department for a residential structure with enclosed areas below the base flood elevation, the owners shall sign a non-conversion agreement stating that the enclosed space shall remain in compliance with KPB 21.06.050(B)(1)(b)(iv). The non-conversion agreement shall be recorded by the Kenai Peninsula Borough placing future buyers of properties on notice of the hazards of enclosed spaces below the base flood elevation and the requirements to keep the permitted structure compliant with KPB floodplain regulations.

c.

For zones AH and AO, drainage paths are required around structures on slopes to drain floodwaters away from proposed structures.

2.

Nonresidential Construction. New construction and substantial improvement of any commercial, industrial or other nonresidential structure shall either have the lowest floor, including basement, elevated to the level of the base flood elevation; or, together with attendant utility and sanitary facilities, shall:

a.

Be floodproofed so that below the base flood level the structure is watertight with walls substantially impermeable to the passage of water;

b.

Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy;

c.

Be certified by a registered professional engineer or architect that the standards of this subsection are satisfied. Such certifications shall be provided to the official as set forth in KPB 21.06.040(C)(4)(b).

d.

Nonresidential structures that are elevated, not floodproofed, must meet the same standard for space below the lowest floor as described in KPB 21.06.050(B)(1)(b).

e.

Applicants floodproofing nonresidential buildings shall be notified that flood insurance premiums will be based on rates that are 1 foot below the floodproofed level (e.g. a building constructed to the base flood level will be rated as 1 foot below that level).

f.

For zones AH and AO, drainage paths are required around structures on slopes to drain floodwaters away from proposed structures.

3.

Manufactured Homes. All manufactured homes to be placed or substantially improved within Zones A1-30, AH, and AE shall be elevated on a permanent foundation such that the lowest floor of the manufactured home is at or above the base flood elevation and be securely anchored to an adequately anchored foundation system in accordance with the provisions of subsection (A)(1) of this section.

4.

Recreational vehicles. Recreational vehicles that are placed on sites within a Special Flood Hazard Area as identified by the current effective FIRM or DFIRM panel are required to either:

a.

Meet the requirements of chapter 21.06.050(A) and (B), or

b.

Be on the site for fewer than 180 consecutive days, or

c.

Be fully licensed and ready for highway use, on its wheels or jacking system, and attached to the site only by a quick disconnect type utilities and security devices.

5.

Before regulatory floodway. In areas where a regulatory floodway has not been designated, no new construction, substantial improvements, or other development (including fill) shall be permitted within Special Flood Hazard Area zones AE, A1-A30 as identified in the current effective FIRM or DFIRM panel at that location unless the applicant demonstrates in the application 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.

6.

Fuel storage tanks. Any fuel storage tanks shall be elevated above the base flood elevation or made watertight and anchored to resist flotation, collapse, and lateral movement. The tank must also be installed within an impervious containment basin of a size sufficient to contain 110 percent of storage capacity plus 12 inches of freeboard.

7.

Logging or clearing. Within any special flood hazard area of the current effective FIRM or DFIRM, logging or clearing may not increase runoff and/or erosion to such levels that it may significantly damage the floodplain function, riparian habitat or wetlands.

C.

Floodways. Located within flood hazard areas established in KPB 21.06.030(B) are areas designated as floodways. Since the floodway is an extremely hazardous area due to erosion potential and the velocity of floodwaters which carry debris, the following provisions apply:

1.

All encroachments, including fill, new construction, substantial improvements, and other development are prohibited unless certification by a registered professional engineer or architect is provided demonstrating that encroachments shall not result in any increase in flood levels during the occurrence of the base flood discharge.

2.

If subdivision (1) of this subsection is satisfied, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of this section.

D.

Coastal High Hazard Areas. Where FEMA has identified coastal high hazard areas (Zones V, VE, and V1-V30) on the FIRM or DFIRM, construction shall meet the following requirements in addition to all other provisions in this chapter:

1.

All new construction shall be located landward of the reach of mean high tide and shall be anchored to prevent unintended lateral movement, floatation or collapse.

2.

All new construction, manufactured homes, and substantial improvements within coastal high hazard areas shall be elevated on adequately anchored pilings or columns such that:

a.

The bottom of the lowest horizontal structural member of the lowest floor (excluding the pilings or columns) is elevated to or above the base flood level; and

b.

The pile or column foundation and structure attached thereto is anchored to resist flotation, collapse and lateral movement due to the effects of wind and water loads acting simultaneously on all building components. Wind and water loading values shall each have a 1 percent chance of being equaled or exceeded in any given year (100-year or 1-percent annual exceedence probability mean recurrence interval); and

c.

A registered professional engineer or architect shall develop or review the structural design, specifications and plans for the construction and shall provide a certification that the design and methods of construction to be used are in accordance with accepted standards of practice for meeting the provisions of subdivisions (2)(a) and (2)(b) of this subsection. The certification and related records will be maintained in the planning department permit files in perpetuity.

3.

All new construction and substantial improvements shall have the space below the lowest floor free of obstructions or constructed with breakaway walls. Such enclosed space shall not be used for human habitation and must be in compliance with the residential construction standards in KPB 21.06.050(B)(1)(b)(iv) and (v). For the purpose of this section, a breakaway wall shall have a design safe loading resistance of not less than 10 and no more than 20 pounds per square foot. Use of breakaway walls which exceed a design safe loading resistance of 20 pounds per square foot (either by design or when so required by local or State codes) may be permitted only if a registered professional engineer or architect certifies that the designs proposed meet the following conditions:

a.

Breakaway wall collapse shall result from a water load less than that which would occur during the base flood; and

b.

The elevated portion of the building and supporting foundation system shall not be subject to collapse, displacement, or other structural damage due to the effects of wind and water loads acting simultaneously on all building components (structural and nonstructural). Maximum wind and water loading values to be used in this determination shall each have a 1 percent chance of being equaled or exceeded in any given year (100-year or 1-percent annual exceedence probability mean recurrence interval).

4.

The use of fill for structural support of buildings within coastal high hazard areas on the FIRM or DFIRM is prohibited.

5.

Manufactured Homes. All manufactured homes to be placed or substantially improved within coastal high hazard areas shall meet the requirements for new and substantial improvement construction.

(Ord. No. 2016-36 , § 3, 10-11-16; Ord. No. 2013-29 , § 7, 8-6-13; Ord. No. 88-7, § 2(part), 1988)