Flood Maps

On this page:
  1. Flood Hazard Mapping
  2. Flood Map Revisions
  3. Google Maps and FEMA Flood Maps—Connected!
  4. FEMA NFHL
  5. New Coastal Flood Risk Webpages and Email List

Flood Hazard Mapping

Through its Flood Hazard Mapping Program, the Federal Emergency Management Agency (FEMA) identifies flood hazards, assesses flood risks, and partners with states and communities to provide accurate flood hazard and risk data that will guide mitigation actions. Flood hazard mapping is an important part of the National Flood Insurance Program (NFIP), as it is the basis of the NFIP regulations and flood insurance requirements. FEMA maintains and updates data through Flood Insurance Rate Maps (FIRMs) and risk assessments. FIRMs include statistical information such as data for river flow, storm tides, hydrologic/hydraulic analyses, and rainfall and topographic surveys. FEMA uses the best available technical data to create the flood hazard maps that outline your community’s different flood risk areas.

For more information about FEMA’s Flood Hazard Mapping click here.

Biker in Baltimore after Hurricane Isabel. Photo Credit: Max Franz
Biker in Baltimore after Hurricane Isabel. Photo Credit: Max Franz

In 2012, the City digitized its floodplain maps, which now allow for the integration of floodplain information with existing geographic information systems (GIS) resources. In addition to this upgrade, the City also updated and adopted its non-tidal floodplain maps, which will assist with both mitigation and adaptation efforts.

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Flood Map Revisions

In July 2012, the U.S. Congress passed the Biggert-Waters Flood Insurance Reform Act of 2012 (BW-12), which calls on FEMA to make a number of changes to the way the NFIP operates. To strengthen the NFIP financially, Section 100205 of the new law requires FEMA to begin charging rates that reflect true flood risk; artificially low rates and deep subsidies are no longer sustainable.

This new law mandated Baltimore’s systematic effort to update the City’s Flood Insurance Rate Maps (FIRMs) according to FEMA’s review of existing Special Flood Hazard Areas (SFHA). The new FIRMs will impact flood insurance policies so that rates more accurately reflect flood risks.

This significant revision will affect many property owners in Baltimore City. Some property owners will see their rates increase, while others will find that their premiums are significantly lower. To help property owners with this adjustment, Baltimore is in the process of becoming a Community Rating System (CRS) community.

Beginning October 2013, premiums for pre-FIRM business properties, severe repetitive loss properties (1–4 residences), and properties on which claims payments exceed fair market value will increase by 25% annually until they reflect the full-risk rate. Routine rate revisions will also include a 5% assessment to build a catastrophic reserve fund. Phasing-out of both grandfathering and the Preferred Risk Eligibility Extension will begin in 2014 and rates are anticipated to rise 20% per year over a 5-year period until they reach full risk rates.

FOR PROPERTIES REMOVED FROM THE SFHA, policyholders will see significant decreases in flood insurance rates. Rate changes take place when Baltimore’s new FIRMs are adopted. It’s important to note, however, that new maps do not consider the likelihood of more extreme and unpredictable impacts related to climate change. In 2013, the Disaster Preparedness Project and Plan (DP3) modeled these predicted climate scenarios. The outcome of this in-depth analysis indicates that these areas are still considered to be high-risk.

The City of Baltimore strongly recommends that property owners take advantage of lower flood insurance rates and retain their policies. More than 25% of flood claims are made by property owners located outside the SFHA. The City expects this percentage to grow with these map changes.

IF YOUR PROPERTY REMAINS WITHIN THE SFHA, you may notice changes to your current insurance policy. Upon policy renewal, premiums have the potential to increase 25% a year until full-risk rates are reached. Only 5% of policyholders will see this increase immediately.

Subsidies, or flood insurance discounts, are also being phased out. Most policies (81%), however, are not subsidized. Some subsidized policyholders will see their premiums decrease; some premiums will be unchanged; and some will see minor to large increases.

Property owners who face increased premiums should discuss options such as verifying their actual risk, increasing their deductible, or taking mitigation steps. The City is working to lower rate increases by becoming Community Rating System (CRS) certified.

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Google Maps and FEMA Floodmaps Connected!

For more information visit https://hazards.fema.gov/femaportal/wps/portal/NFHLWMSkmzdownload

Baltimore Google Earth Flood Map
Google Earth Flooding Map of Baltimore’s Inner Harbor

Google Earth is a popular Internet application through which users can view maps. This web site provides zipped Keyhole Markup Language (.kmz) files through which users can view map overlays created from FEMA’s National Flood Hazard Layer on Google Earth images.

You must already have the Google Earth application installed on your computer to use these files. The starting point for obtaining the software is http://earth.google.com. Information about the system requirements needed for your computer to run the software is available through http://earth.google.com/support. A user guide is available at http://earth.google.com/userguide.

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FEMA NFHL

“FEMA NFHL” is a general application that provides for the display of flood hazard zones and labels, floodways, Coastal Barrier Resources System and Otherwise Protected Area units, community boundaries and names, base flood elevations, cross sections and coastal transects and their labels, hydraulic and flood control structures, flood profile baselines, coastal transect baselines, limit of moderate wave action lines, river mile markers, and Flood Insurance Rate Map and Letter of Map Revision boundaries and numbers. Additional reference layers include the status of NFHL data availability, point locations for Letters of Map Amendment (LOMAs) and Letters of Map Revision Based on Fill (LOMR–Fs). You control the information displayed by turning layers on and off. A basic knowledge of Google Earth and FEMA flood hazard information will help users of this application.

The name of each layer is hyperlinked to a description of the layer, the map symbols used for the layer, and links to other FEMA web sites relevant to the layer. If a layer is turned on, clicking the text below the name of the layer (text that starts with “Draws at…”) zooms the Google Earth view to a sample display of the layer. Layers are organized for display at one or more of three “eye altitude” (map scale) ranges in Google Earth: status maps at high altitudes, regional overviews of flood hazards at medium altitudes, and detailed flood hazard maps at low altitudes. Click on the hyperlinked folder name of the application to see the altitudes at which data in the layers are displayed.

For best performance please delete or turn off previous versions of the “Stay Dry” or “FEMA NFHL” folders that you have loaded in Google Earth before using the new version of “FEMA NFHL.”

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New Coastal Flood Risk Webpages and Email List

The FEMA Federal Insurance & Mitigation Administration (FIMA), Risk Analysis Branch is pleased to announce brand new Coastal Flood Risk webpages on FEMA.gov and Coastal email list. As a result of FEMA Headquarters’ collaboration with Federal Coastal Partner Agencies, FEMA Regions, and contractors, the Coastal Flood Risk webpages:

To meet the needs of the wide variety of citizens concerned with coastal flood hazards, tailored webpages were also developed for the following stakeholders:


Image comparing Baltimore's new and old floodplains

Off to the side you can find a link to seethe revised flood maps  for Baltimore (see the above screenshot). If you have problems with these maps, please contact Planning for assistance at 410-396-7526410-396-7526.

What are these Maps?

These maps are prepared by the National Flood Insurance Program (see Flood Insurance). They identify flood risk area for the 1% (aka 100-year storm) in which regulations and insurance are required. The “100-year” storm represents a probability. Download this USGS poster:  USGS_100-year-flood

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