Special Flood Hazard Areas & Flooding Information

Maintenance of Drainage Systems

Maintaining the drainage system on private property is the owner’s responsibility. Please see below for tips on how to reduce the chance of stormwater from ponding on your property.

1. Do not dump or throw anything into ditches or streams. Dumping yard waste and other debris can accumulate and plug ditches, culverts, and channels thereby increasing the risk of flooding during storm events as rainwater will have nowhere to go.
2. Maintain your drainage system.
   • Clean out roof gutters twice a year.
   • Direct flow from downspouts away from your foundation without directing stormwater discharge onto neighboring properties.
   • Never discharge water over the edge of a steep slope.
   • Properties with stormwater detention systems should have these systems checked on an annual basis to ensure that they are functioning as intended.
3. If a public street drain or ditch appears to be blocked by snow or other debris call the Town of Boone Public Works Department at (828-268-6230) to report the issue.

What are Floodplains?

Floodplains are the areas along streams or rivers that are likely to experience repeated flooding. Over time, nature and man-made development have shaped the floodplain to hold excess waters. In Boone, several rivers and streams converge to form the headwaters of the South Fork of the New River. Nature has formed these floodplains to flood and to carry a large volume of stormwater. Simply put, floodplains are meant to flood. Therefore, floodplains can be dangerous during heavy storm events and should be avoided when water is present.

Since 1979, when the Town entered the National Flood Insurance Program (NFIP), building in local floodplains within the Town of Boone has been restricted (Town of Boone Unified Development Ordinance Article 30 Flood Damage Prevention). In 1968 Congress created the NFIP to help provide a means for property owners to financially protect themselves from the possible damage of structures resulting from flood events. The program is intended to supplement typical homeowner insurance policies, which do not cover damage to structures resulting from a flood. The NFIP offers flood insurance to homeowners, renters, and business owners if their community participates, specifically through the adoption and enforcement of regulations designed to mitigate/reduce flood risk.  To find out more about flood insurance, please visit www.floodsmart.gov..

Flood Insurance Rate Map (FIRM)

Through participation in the NFIP, the Town of Boone has adopted Flood Insurance Rate Maps (FIRM), prepared by the State of North Carolina Federal Emergency Management Agency. The adopted FIRMs provide the Town of Boone with the data needed to adopt and implement more comprehensive floodplain management measures. These maps note the areas within the Town of Boone that are susceptible to flooding. To help understand these maps, and to clear up misconceptions of terminology, below is a brief explanation of some common terminology used when discussing FIRMs within the Town of Boone:

• Flood Insurance Rate Map (FIRM)

  An official map of a community, issued by the Federal Emergency Management Agency, on which both the special flood hazard areas and the risk premium zones applicable to the community are delineated.

• Floodplain

  Any land area susceptible to being inundated by water from any source.

• Base Flood

  In order to have common standards, the NFIP adopted a baseline probability called the base flood. The base flood is the one-percent annual chance flood. The one-percent annual chance flood is the flood that has a one-percent (one out of 100) chance of occurring in any given year. The base flood, which is also informally referred to as the 100-year flood, is the national standard used by the NFIP and all Federal agencies for the purposes of requiring the purchase of flood insurance and regulating new development.

• 100 Year Flood

  The term “100-year flood” is often misconstrued. Commonly, people interpret the 100-year flood definition to mean “once every 100 years.” This is wrong. You could experience a 100-year flood two times in the same year, two years in a row, or four times over the course of 100 years. You could also not experience a 100-year flood over the course of 200 or more years. To avoid confusion (and because probabilities and statistics can be confusing), the NFIP uses the term “base flood.” A 100-year base flood is defined as having a one percent chance of being reached or exceeded in any single year. Thus, the 100-year flood also is called the “one-percent annual chance flood.”

  “100-year flood” and “base flood” both refer to a flood that has a one percent chance of occurring in any given year. The terms “base flood,” “100-year flood,” and “one-percent annual chance flood” are often used interchangeably.

• Special Flood Hazard Area (SFHA)

  The land area covered by the floodwaters of the base flood is the base floodplain. On NFIP maps, the base floodplain is called the Special Flood Hazard Area (SFHA). The SFHA is the area where the NFIP’s floodplain management regulations must be enforced by the community as a condition of participation in the NFIP and the area where the mandatory flood insurance purchase requirement applies. Simply defined, the SFHA is the land in the floodplain subject to a 1% or greater chance of being flooded in any given year. The SFHA includes Zones A, AO, AH, A1-30, AE, A99, AR, AR/A1-30, AR/AE, AR/AO, AR/AH, AR/A, VO, V1-30, VE, and V. Note: The only regulated SFHA zone within the Town of Boone’s jurisdiction is “AE”.

• Zone AE Floodway

  The floodway is the channel of a stream plus any adjacent floodplain areas that must be kept free of encroachment so that the 1% annual chance flood can be carried without substantial increases in flood heights.

• Zone AE

  The base floodplain where base flood elevations are provided.

• Zone X

  Known as “Other Flood Areas”, areas outside of the SFHA with 0.2% annual chance of flood; areas of 1% annual chance flood with average depths of less than one foot or with drainage areas less than one square mile. Note: Currently unregulated zone within the Town of Boone.

• Base Flood Elevation (BFE)

  The computed elevation to which floodwater is anticipated to rise during the base flood. When the BFE has not been provided in a “Special Flood Hazard Area”, it may be obtained from engineering studies available from a federal, state, or other source using FEMA-approved engineering methodologies. This elevation, when combined with the “Freeboard”, establishes the “Regulatory Flood Protection Elevation”.

• Freeboard

  The height added to the base flood elevation (BFE) to account for the many unknown factors that could contribute to flood heights greater than the height calculated for a selected size flood and floodway conditions, such as wave action, blockage of bridge openings, and the hydrological effect of urbanization of the watershed. The base flood elevation (BFE) plus the freeboard establishes the “Regulatory Flood Protection Elevation”.

• Regulatory Flood Protection Elevation

  The “base flood elevation” plus the “freeboard” of two feet. In “special flood hazard areas” where no BFE has been established, this elevation shall be at least two feet above the highest adjacent grade.

• Elevation Certificate

  The permit file must have an official record that shows new buildings and substantial improvements in all identified Special Flood Hazard Areas (SFHAs) are properly elevated. This elevation information is needed to show compliance with the floodplain management ordinance. This certificate can be used by the property owner to obtain flood insurance. The Town of Boone is required to use the FEMA Elevation Certificate.

Community Rating System (CRS)

The Town of Boone has also chosen to voluntarily participate in the NFIP’s Community Rating System (CRS) program. CRS is a voluntary, incentive-based program, through the NFIP that recognizes and encourages community floodplain management activities that exceed the minimum NFIP standards. Depending upon the community’s level of participation, flood insurance premium rates for policyholders can be reduced up to 45%. The adoption and enforcement of these ‘heightened’ development restrictions allow local property owners receive savings on their flood insurance premiums.

Besides the benefit of reduced insurance rates, CRS floodplain management activities enhance public safety, reduce damages to property and public infrastructure, avoid economic disruption and losses, reduce human suffering, and protect the environment.

Floodplain Development Permit

A Floodplain Development Permit is required for any disturbance within the floodplain prior to starting any development activity, including, but not limited to the clearing of land. Before any development can take place on a property where a portion of or the entire tract is located in the Special Flood Hazard Area, a determination must be made that the proposed development is permitted on the property. 

The first step in this process is to locate the parcel on the Flood Insurance Rate Map. If it is determined that the proposed development would be located within the Special Flood Hazard Area, it is necessary to consult with Planning and Inspections Staff to determine what restrictions and standards must be applied to the proposed development.