16. OVERLAY ZONES
16.1. FLOOD OVERLAY
16.1.1. Purpose: The purpose of the Flood Overlay Zone is to promote the public health, safety and general welfare and to minimize public and private losses due to flood conditions in specific areas in a manner designed to protect human life and health, to minimize expenditure of public funds for flood control projects, to minimize the need for rescue and relief operations resultant from flood events, to minimize damage to public facilities and to assure the availability of flood insurance through compliance with Federal Emergency Management Agency flood management regulations.
16.1.2. Basis for Establishment: The areas of special flood hazard are as identified by the Federal Insurance Administration “Flood Insurance Study for the Unincorporated Areas of Boundary County,” dated August 2, 1982, and any revisions thereto, with accompanying Flood Insurance Maps, and any revisions thereto, as maintained by the office of planning and zoning, which are hereby adopted by reference and declared to be a part of this ordinance.
16.1.3. Applicability: The provisions established within this section do not abrogate any other provision of this ordinance but add additional restrictions and requirements in all areas of special flood hazard within the unincorporated areas of Boundary County, as identified on the Boundary County Flood Insurance Rate Map (FIRM), which lie in those areas with flood zone designations that include the letter “A.” No development shall hereafter occur within these areas without compliance with all development and subdivision provisions established herein.
16.1.4. Disclaimer of Liability: The provisions of this section are considered reasonable for regulatory purposes based on scientific and engineering considerations. Large floods have and will occur, and the provisions in this section do not imply that compliance will protect against flood damage or that the potential for flood damage exists solely within the areas defined. This section shall not create liability on the part of Boundary County, Idaho, any officer or employee thereof, or the Federal Insurance Administration, for any flood damages that result from reliance on the provisions of this section or on any administrative decision lawfully made hereunder.
16.1.5. Penalties for Noncompliance: Violation of the construction provisions, Section 16.1.8. constitute an infraction pursuant to Section 4.1.1.7. Violations may be deemed cumulative with violations of other provisions established by this ordinance in its entirety. In the event development occurs on private property in violation of this section and enforcement action fails to remedy the violation, the National Flood Insurance Program shall be so notified, in writing, so as to retain flood insurance benefits to the remainder of citizens of Boundary County. Failure to comply with structure placement requirements of the flood plain overlay constitute a misdemeanor pursuant to Section 4.1.3.1.
16.1.6. Administration:
16.1.6.1. The Boundary County Zoning Administrator is designated flood plain administrator for the unincorporated lands of Boundary County and has primary responsibility for ensuring compliance with the provisions established herein and for initiating enforcement action for violations.
16.1.6.2. Prior to the onset of development or construction, a development permit application will be obtained from the zoning administrator, which will be used to identify the FIRM flood zone designation in the area in which the development is proposed. Where development is proposed in a flood zone designation A, the following provisions shall apply in addition to other requirements.
16.1.7. Base Flood Elevation:
16.1.7.1. Where base flood elevation has been determined through FIRM, data contained in the National Flood Insurance Program Flood Boundary and Floodway maps, dated August 2, 1982, and as revised, shall be used to determine base flood elevation.
16.1.7.2. Where the base flood elevation in an A Zone have not been determined through FIRM, it shall be the applicant’s responsibility to engage a professional engineer or licensed surveyor to establish the base flood elevation at the location where development is proposed through hydrological and hydraulic study; or to provide base flood elevation and floodway data from a Federal, State or other source so as to establish a reasonable elevation sufficient to protect against flood damage to be used as the base flood elevation, following procedures established in FEMA 265/July 1995, “Managing Floodplain Development in Approximate Zone A Areas: A Guide for Obtaining and Developing Base (100-Year) Flood Elevations.” (http://www.fema.gov/pdf/fhm/frm_zna.pdf).
16.1.8. Provisions for Flood Hazard Reduction: In all areas of special flood hazard, the following standards are required and will be depicted on or included with the development permit application:
16.1.8.1. Anchoring: All new construction and substantial improvements will be anchored to prevent flotation, collapse or lateral movement of the structure, to include mobile and manufactured homes, which will be installed so as to minimize flood damage.
16.1.8.2. Drainage: Adequate storm and flood water drainage paths are required so as to direct storm and flood water around and away from proposed structures and to preclude increasing flood or runoff damage on adjacent lots or parcels.
16.1.8.3. Construction Materials and Methods: All new construction and substantial improvements will be constructed with materials and utility equipment resistant to flood damage, using methods and practices that minimize flood damage. Electrical, heating, ventilation, plumbing and air conditioning equipment and other service facilities shall be designed and/or elevated or located so as to prevent water from entering or accumulating within the components during flood events.
16.1.8.4. Utilities, Water: All new and replacement water supply systems will be designed to minimize or eliminate the infiltration of floodwaters into the system.
16.1.8.5. Utilities, Sanitary Sewage: New and replacement sanitary sewage systems will be designed to minimize or eliminate infiltration of flood waters into the system and discharge from the system into flood waters. On-site waste disposal systems will be located to avoid impairment to them or contamination from them during flooding.
16.1.8.6. Subdivisions: When a platted subdivision is proposed within an area of special flood hazard, the design will be consistent with the need to minimize flood hazard, to include the placement of utilities and facilities such as gas, sewer, electrical and water systems. A storm and floodwater runoff plan will be included so as to depict drainage. Where FIRM base flood elevation is not available, said data will be generated pursuant to Section 17.1.7.2 prior to final plat approval.
16.1.9. Specific Standards:
16.1.9.1. Floodways: Located within areas of special flood hazard are areas designated as floodways. The floodway is an extremely hazardous area due to the velocity of floodwaters. Within the floodway, encroachment including fill, new construction, substantial improvement or other development, is prohibited unless and until certification by a registered professional civil engineer is provided demonstrating through hydrologic and hydraulic analyses performed in accordance with standard engineering practice that encroachment or development will not result in any increase in flood levels during the base flood discharge (no-rise analysis). All development meeting no-rise provisions will in addition meet provisions established below. In areas where a regulatory floodway has not been designated, no development will be permitted unless it is certified by a registered professional civil engineer 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 within any point within Boundary County.
16.1.9.2. Residential Construction: New construction and substantial improvements of any residential structure within an A-designated flood zone will be certified by a surveyor or engineer to have the lowest floor, including the basement, elevated not less than two feet above the base flood elevation. Fully enclosed areas below the lowest floor that are subject to flooding are prohibited, and will be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of flood waters. Designs for meeting this requirement to FEMA standards will be certified by a registered professional engineer or architect and will require completion of an Elevation Certificate. This provision may be waived with certification that the lowest floor of the residential structure is built a minimum of three feet above the highest adjacent grade.
16.1.9.3. Non-residential Construction: New construction and substantial improvement of any commercial, industrial or other non-residential structure within an A-designated flood zone will either have the lowest floor, including basement, elevated at or above the base flood elevation, or be certified by a registered professional engineer or architect that the design and methods of construction are in accordance with FEMA standards, and will require completion of a flood proofing certificate and/or elevation certificate. Non-residential structures that are elevated and not flood proofed must meet the same standards for space below the lowest floor as established at Section 17.1.8, above.
16.1.9.4. Manufactured Homes: All manufactured homes to be placed or substantially improved on sites within an A flood zone will be elevated on a permanent foundation such that the lowest floor of the manufactured home is at least one foot above the base flood elevation and be securely anchored to an adequately designed foundation system to resist flotation, collapse and lateral movement, certified by completion of an elevation certificate. The chassis of the manufactured home will be 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 securely anchored.
16.1.9.5. Recreational Vehicles: Recreational vehicles placed on sites within an A flood zone will have no permanently attached additions and be fully licensed and ready for highway use, on its wheels or a jacking system, and attached to the site only by quick-disconnect type utility hookups and security devices; or shall meet the requirements of Section 17.1.8, above, as certified by completed elevation certificate.
16.1.9.6. Critical Facilities: Any permanent facility or structure for which even a slight chance of flooding might be too great to risk, including schools, hospitals, nursing homes, police, fire and emergency response installations, or installations which produce or store hazardous materials or waste are hereby prohibited within any A flood zone. When critical facilities are proposed in B flood zones, they will be flood proofed or constructed with the lowest floor at least one foot above the highest adjacent grade, and certified by completion of a flood proofing certificate and/or elevation certificate.
16.1.10. Amending National Flood Insurance Program Maps: Property owners may request from the administrator FEMA application forms and instructions for seeking to have lots, parcels or development areas removed from the special flood hazard area, or to have base flood elevations or floodway boundaries amended. Upon determination by FEMA and the National Flood Insurance Program, the applicant may provide written proof of the determination to the administrator and initiate or continue the development application process.
16.1.11. Variance and Appeal: Variances and appeals regarding matters pertaining to special flood hazard areas will be processed and considered as established in Section 13: Variance, and Section 14: Mediation and Appeal, but in hearing a variance or appeal involving an area of special flood hazard, the following will be given additional consideration:
16.1.11.1. The danger that materials may be swept onto other lands to the injury of others.
16.1.11.2. The danger to life and property due to flooding or erosion.
16.1.11.3. The susceptibility of the proposed facility and its contents to flood damage and the effect of such damage on the property owner.
16.1.11.4. The importance of the services provided by the proposed development to the community.
16.1.11.5. The necessity to the facility of a waterfront location.
16.1.11.6. The availability of alternative locations not subject to flooding or erosion.
16.1.11.7. The safety of access for normal and emergency traffic during a flood event.
16.1.11.8. The cost of providing governmental services during and after a flood event.
16.1.12. A variance of standards established herein may only be granted when:
16.1.12.1. The applicant shows sufficient cause to require variance; and
16.1.12.2. Failure to grant the variance would result in undue hardship to the applicant; and
16.1.12.3. Granting the variance will not result in increased flood heights or pose a risk to the public safety or result in undue public expense.
16.1.13. In addition to other administrative requirements established, the administrator will notify the Federal Insurance Administration, in writing, whenever a variance or appeal results in relaxing standards established by this section.
16.2. AIRPORT OVERLAY:
16.2.1. Applicability: The provisions established within this section do not abrogate any other provision of this ordinance but add additional restrictions and requirements in all areas in county jurisdiction that lie within airport overlay areas as defined in the Boundary County Airport Overlay Ordinance, maintained by the Boundary County Airport and incorporated into the electronic zoning map. No development will hereafter occur within the airport overlay without approval by the airport board or designee indicating compliance, as indicated by signature on the application.
16.2.2. Penalties for Noncompliance: Violations of the provisions of this section are misdemeanors pursuant to Section 4.1.3.2. Upon approval by the board, Boundary County reserves the right to remove any tree or object of natural growth from public or private property found to be in violation of this section.
16.3. WETLANDS/RIPARIAN AREA OVERLAY:
16.3.1. Basis for Establishment: Digital data
depicting wetlands provided the Boundary County GIS Department by the U.S. Army
Corps of Engineers or their designee, and will be adapted for inclusion
as a reference layer on the electronic Boundary County Zoning Map. Riparian
areas will be depicted on the official electronic Boundary County Zoning Map
using the National Hydrography Dataset maintained by the GIS Department.
16.3.2. Applicability: The provisions established within this section do not abrogate any other provision of this ordinance.
16.3.3. Administration:
16.3.3.1. Where a use requiring an administrative development permit is proposed and found to be within or near an identified wetlands/riparian zone, the administrator will notify the applicant and provide the applicant literature as provided by the U.S. Army Corps of Engineers.
16.3.3.2. Where a use subject to public hearing is proposed and found to lie within or near an identified wetlands/riparian overlay, the U.S. Army Corps of Engineers will be notified of said application through the public hearing process, and such finding will be included in staff analysis for consideration.