Digital flood maps have a wide range of potential uses and users. Citizens use the maps to see if their home or property is located within the floodplains. State and community officials use these products to administer floodplain management regulations and mitigate flood damage. Property owners use them to understand if their home or business is at risk of flooding. Lending institutions and federal agencies use the flood maps to determine whether flood insurance is required when making loans and providing grants for the purchase or construction of buildings.
Because we live in a digital age, and because of the great increase of data available, there are many ways that you can view and use digital floodplain maps. These include federal, state, and local services and tools that show the effective flood maps, as well as preliminary map data, base flood elevations, engineering models, and inundation maps. For a more in-depth coverage of how to view and use digital flood maps products, as well as images showing the different map products in use, download the Kentucky Viewing and Using Digital Flood Maps
Kentucky Flood Hazard Portal
The Kentucky Flood Hazard Portal
is an online map service that allows you to easily view all of the effective floodmaps for the Commonwealth of Kentucky. This includes information such as the streams & rivers, the flood hazard zones, FIRM panel boundaries, panel numbers & effective dates, and areas where a Letter of Map Change (LOMA & LOMRs) have been issued.
Users can obtain ‘Approximate Base Flood Elevations’ (BFEs) in A Zones in 119 of 120 counties in the Commonwealth. For BFE elevations in Jefferson Co., see the Louisville MSD information below. To get the BFE in one of the available counties, users must simply click the stream centerline of the stream or river next to their site. A ‘Results’ box will appear that provides you the BFE for where you clicked.
The BFEs available on the Portal can be used for actions such as floodplain permit applications, complying with floodplain building requirements, completing an Elevation Certificate, and for Letters of Map Change applications. BFEs in AE zones are not available at this time from the portal and must be obtained from the County’s Flood Insurance Study (FIS) which are available for download on the Map Service Center. BFEs for sinkhole flooding are currently unavailable on the Portal and must be obtained manually by contacting KYriskMAP@ky.gov
For Surveyors, Engineers, or other technical users, the Portal also allows you to download the HEC-RAS models used to create the effective flood maps. From the results box, click the ‘Download Mode Here’ link. This gives you the option of downloading the effective A zone HEC-RAS models, the Hydraulic and Hydrology Reports, and the Flood Insurance Study (FIS) for your location.
To assist everyone in using the Portal, the Division of Water has put together a User Guide
to help. If you require additional assistance, or have questions about the intended purpose or functionality of this portal site that are not answered by the user guide, please contact the Division of Water, by email at KYriskMAP@ky.gov
or by phone at (502) 564-3410.
FEMA Map Service Center
The Map Service Center (MSC)
is the official public source for flood hazard information produced in support of the National Flood Insurance Program (NFIP). Essentially the MSC is FEMA’s online digital library for all of the country’s flood risk information. The MSC provides users access to the Flood Insurance Rate Map panels, Flood Insurance Studies, Letters of Map Change, and all other flood risk data.
Communities may have several different types of flood maps available at any time. The different types of maps may include Preliminary maps, Pending maps, Effective maps, and Historic maps. FEMA has made all of these map products available from the Map Service Center to view or for download. Learn more about the different products and tools the MSC has to offer
Preliminary Flood Maps
Flood risks can change over time. New development, water flow, & drainage patterns can change dramatically because of surface erosion, land use, and natural forces. Keeping a community’ flood maps up to date is an important step in helping a community protect lives and reduce property damage as a result of flooding.
As the flood map updates occur, preliminary flood maps are available for community members and community elected officials to review. These preliminary maps allows the public an early look at how the changes to the flood maps will affect their homes or properties. While these preliminary maps are not for use in regulating the floodplains, they are made available to better inform everyone of their changing flood risks as well as to allow feedback on the changing maps. Visit the Division’s Flood Map Updates
page to see the preliminary maps available today and to learn more.
FEMA’s Map Service Center
also has preliminary maps available for use and download. Simply find your area of interest by entering it into the search bar, and then select the ‘Show All Products’ button. From there you can select the ‘Preliminary Products’ or ‘Pending Products’ if there are any available for your area.
FEMA developed the Preliminary Map Comparison Tool
allowing users to view, save, and print copies of the Effective and the Preliminary maps side by side in a pdf format. The Comparison tool’s webpage indicates which areas have Preliminary flood map available by highlighting the counties in Purple. Users will be able to use this tool to create a side-by-side comparison of effective flood maps to the preliminary flood maps for each location in which they are interested.
Flood Inundation Mapper
The United States Geological Survey (USGS) has developed a digital mapping program called the Flood Inundation Mapping
program. This program is designed to help communities protect lives and property by providing tools & information to better understand their flood risks and make cost-effective mitigation decisions. The Flood Inundation Mapper combines the flood inundation map libraries with real-time river gauge information & flood forecasts into a tool that can help to communicate when and where it may flood. This tool allows local responders to take actions and make plans that can protect lives and property before or during a flood.
This tool allows the user to select the elevation of the water at the gage using the ‘Flood Tools’ tab. The slider bar in this tab allows the user move the river stages up or down depending what river gage height or elevation they’re interested in, to see how the surrounding community would be affected. Once a river gauge height has been selected, users can then click in the inundated areas to see what the estimated water depths would be at that gauge height.
ArcMap and NFHL Rest Service
For anyone with access to GIS software, FEMA has developed a geospatial database, which brings effective flood map data into your GIS program. This live data layer, called the National Flood Hazard Layer (NFHL)
, is accessed via the web so when FEMA updates the data on their servers, the updates show up automatically in your projects. This allows you to have access to the most up-to-date floodplain maps, LOMA’s and LOMR’s, FIRM Panels, Base Flood Elevations, stream lines, and many other useful layers, without having to store and manage the data locally. Download the Kentucky Viewing and Using Digital Flood Maps
guide for a step-by-step process for adding the NFHL database into your ArcMap projects.