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Frequently Asked Questions about new floodplain maps

    1)     What maps are being updated?
Charlotte-Mecklenburg is updating Special Flood Hazard Area maps and Flood Insurance Rate Maps.

Special Flood Hazard Area (SFHA) maps show land along larger creeks and the Catawba River that has a specific level of flood risk.

Other names for the Special Flood Hazard Area:
        • 100-year floodplain
        • 1% annual chance floodplain
        • mapped floodplain
        • regulated floodplain
        • flood zone
        
The Flood Insurance Rate Map (FIRM) shows varying levels of flood risk within the Special Flood Hazard Area. 

In this FAQ, "floodplain maps" refers to both the official Special Flood Hazard Area maps and official Flood Insurance Rate Maps.

    2)    What is shown on floodplain maps?
The maps show land along bodies of water that is at greater risk of being in a flood. Locally and nationwide, it floods more often in the Special Flood Hazard Area.

Floodplain maps do not show all places where flooding is possible. Instead, floodplain maps show land that has a specific risk of flooding.

Charlotte-Mecklenburg's maps show the Special Flood Hazard Area along hundreds of miles of larger creeks, lakes and the Catawba River. Our local Special Flood Hazard Areas include nearly 17,000 acres of land and more than 4,000 structures.

Floodplain maps can have more than one set of lines. The additional lines show the different levels of flood risk inside the Special Flood Hazard Area.

Localized flooding and drainage problems such as runoff from a neighbor's yard are not shown on floodplain maps.

    3)    What are floodplain maps used for?
Official floodplain maps are used for:
        a) flood insurance
        b) regulating construction and land development.

        a) Flood Insurance
        
If your property is in the FEMA-regulated portion of the Special Flood Hazard Area and you have a mortgage from a federally-regulated lender, you are required to have flood insurance. Learn more about FEMA floodplains in Question 15.

The Flood Insurance Rate Map is used to determine flood insurance rates (cost) for properties inside and outside of the Special Flood Hazard Area. The cost of flood insurance for each property is generally based on the level of risk shown on the Flood Insurance Rate Map and the elevation data of the structure. More about elevation certificates

Flood insurance is usually not required if the structure is outside of the Special Flood Hazard Area. But it still can flood outside the Special Flood Hazard Area. If your property is near a regulated floodplain or in a low-lying area with the potential for flooding or drainage problems, flood insurance is strongly recommended. And flood insurance costs less outside of the Special Flood Hazard Area. More about flood insurance

        b) Development
        
In the Special Flood Hazard Area, there are additional rules for construction, renovation and grading. To make any changes to the land or to structures in the Special Flood Hazard Area, you will need to apply for a Floodplain Development Permit and comply with all floodplain development rules. The additional rules apply to new construction, additions, renovations, repairs, even adding a patio or garage or grading the land. More about floodplain construction and permits

    4)    How can I see the new maps?
The draft and preliminary floodplain maps are available here.

    5)    Why is Charlotte-Mecklenburg updating its floodplain maps?
The maps approved in 2000 are out of date. The data used to draw the 2000 floodplain maps was collected from 1997 to 1999. Since then, flood risks have changed due to urban growth, natural forces such as changes in climate, and storm water projects to improve drainage and temporarily hold some floodwater.

In addition, the new maps are more accurate. They use updated information about land use and development. And technology has improved since the existing maps were created. To precisely depict our community's terrain, LIDAR was used to gather data for the new maps. LIDAR is similar to radar and SONAR but uses laser pulses to show detailed contours of the earth's surface. That helps us figure out where floodwater is likely to flow.

Accurate information about flood risk inside and outside of the SFHA is important for both property owners and local officials to take appropriate action to protect lives and property from flooding.
    6) Is all of Charlotte-Mecklenburg getting new floodplain maps?
Yes. The remapping is being done in phases over several years.

    Phase 1: central and southeast Charlotte-Mecklenburg
    Phase 2: western Charlotte-Mecklenburg including most of the Catawba River
    Phase 3: northeast Charlotte-Mecklenburg
    Phase 4: Lake Wylie and Lake Norman

  7) When will the new floodplain maps take effect?
    Phase 1: February 19, 2014
    Phase 2: sometime in 2015
    Phase 3: 2016
    Phase 4: undetermined​
Map showing Phases 1, 2 and 3 
   8)    Why does it take several years from the time the maps are first shown to the public until they take effect?
It takes time to ensure that the maps are accurate. The process includes mandatory review periods giving the public several chances to look at the proposed maps and ask questions. The process also gives federal regulators at least a year to study the specific details and make sure the mathematical and engineering data are accurate.

The stages of the remapping process are:
        » ​Planning stage: preparing for engineering and surveying work
        » Development stage: data gathering and creation of draft maps
        » Draft stage: draft maps presented to the public with a comment period
             Draft maps are sent to the federal government for a year-long review
        » Preliminary stage: tentative federal approval and the maps are considered "preliminary"
             Preliminary maps are used for regulation on some construction and building renovation
             Publication in the Federal Register telling when the maps are to become effective
             Preliminary maps presented to the public with an appeal period
             Adoption by local officials
        » Effective stage: new maps take effect for flood insurance and all regulatory purposes

    9)     How will the new floodplain maps affect me?
It depends. Some properties will not be affected by the new maps; their flood risk remains the same. Other structures will be mapped into a higher risk area or show a new Base Flood Elevation. Some properties will be mapped into lower-risk areas than before.

Of Charlotte-Mecklenburg's revised floodplain maps completed so far (Phases 1 and 2):
        • approximately 7 percent more buildings now outside the Special Flood Hazard Area will be inside
           the SFHA when the final maps are approved.
        • approximately 49 percent of buildings currently in the Special Flood Hazard Area will be outside the
           SFHA when the final maps are approved.

These figures do not include vacant land or parcels where the largest structure is less than 600 square feet in size.

    10)    If my property has never flooded before, how can I be in a Special Flood Hazard Area?
Flood risk is not based on whether you've flooded in the past. Flood risk is based on where water is expected to flow during heavy or prolonged rain. Standard engineering and mathematical calculations are used to determine how far the floodwater will spread, how deep the floodwater will be and how the floodwater will affect your particular building.

Floodplain maps don't create the risk. Instead, they show the risk that already exists.

    11)    What happens if my property was in a lower-risk area before but new maps show it's at a higher risk of flooding?
The insurance and development requirements change. If you have a mortgage from a federally-regulated lender and the new maps show your structure is now in the FEMA-regulated portion of Special Flood Hazard Area, you will be required to buy a flood insurance policy. If you don't have a mortgage, it is still strongly recommended that you have flood insurance for both your structure and your contents.

To get an idea of how much a flood insurance policy might cost for your home or business, contact the agent that provides your homeowner's or business insurance.

If the new maps show your property is now in the Special Flood Hazard Area, you will have to comply with the more restrictive development (construction, renovation and repairs) regulations described in Question 3.

    12)    What happens if my property was in a high-risk area before but new maps show it's at a lower to moderate risk of flooding?
The insurance and development requirements change. When a building has moved from a high-risk area to a low-risk area a Flood Hazard Map, there is no longer a federal mandate to purchase flood insurance for that building. However, Mother Nature doesn't pay attention to lines on a floodplain map. Flood insurance is still strongly recommended.

When the new maps are adopted, you may be eligible for a lower-cost Preferred Risk Policy (PRP). Contact your flood insurance agent to submit a PRP application.

    13)    Doesn't my homeowner's insurance policy cover flooding?
No, it does not. Flood damage is only covered by a separate flood insurance policy. More about who should buy flood insurance    

    14)     How do I get flood insurance?
Contact the insurance agency that provides your homeowner's or business insurance. Although flood insurance is sold by private agents, all flood insurance policies are through the National Flood Insurance Program (NFIP). The NFIP sets all premiums and exclusions. More about how to buy flood insurance and how much it costs

    15)    What are the FEMA and Community Floodplains?
Charlotte-Mecklenburg floodplain maps show two types of floodplains. Both are in the Special Flood Hazard Area. The FEMA Floodplain is where flooding is likely to occur now. Flood insurance is required and development restrictions apply.

The Community Floodplain shows the land at greatest risk of flooding in the future, based on expected land development upstream. In the Community Floodplain, flood insurance is strongly recommended and development restrictions apply. More about FEMA and Community Floodplains

    16)     What's being done to fix the flooding?
Flooding is a natural occurrence caused by heavy rain. When it rains hard, the excess water has to go somewhere. Most options to reduce flooding on creeks, rivers and lakes are expensive and may not work. Learn more

    17)    What if I believe the new floodplain maps are wrong?
Floodplain maps are based on the best data available to engineers and local officials. If you believe you have more accurate data, you may submit it to Charlotte-Mecklenburg Storm Water Services as part of an appeal. This data can include an authorized Elevation Certificate, topographic map or detailed hydraulic and hydrologic data.

    18)    Who do I contact if I have questions?
Charlotte-Mecklenburg Storm Water Services at 704-432-RAIN (7246).​