Finding and Using Additional Hazard Information

Following are some sources for additional information on hazard risks your community may face. For details on how to use this information to help protect your community, see where to use additional information on coastal hazard risks.

Understanding Your Community’s Exposure

The first step towards making your community more resilient to disasters is understanding and prioritizing its risks: the Mississippi-Alabama Sea Grant Consortium has put together a very useful tool called the Coastal Resilience Index to help you do just that. Yes, it’s tweaked for the Gulf Coast, but it’s a great starting point for a conversation.

Hurricane Probability

For the latest (April, 2009) statistics on the likelihood of your county being struck by a hurricane, see The United States Landfalling Hurricaneor Web Project.

Shoreline Change History

The Massachusetts Office of Coastal Zone Management’s (CZM) Historic Shoreline Change Project website provides detailed shoreline change maps showing the relative positions of historic shorelines, along with information on how to interpret these maps and data. (For South Shore communities [Hull to Plymouth], more recent data is available in The South Shore Coastal Hazards Characterization Atlas). Shoreline change and other spatial data are also available through the Massachusetts Ocean Resource Information System (MORIS), CZM’s online mapping tool. The US Geological Survey has recently released a study on shoreline change in New England and the Mid-Atlantic.
Communities seeking more information on shoreline change and the risks that come with it can download a PDF of the Heinz Center’s Evaluation of Erosion Hazards.

Sea Level Rise Data and Projections

While the causes and future rates are still being debated, there is a general scientific consensus that sea levels are rising. Consequently, the effects of future, higher, sea levels should be considered when making siting and design decisions. For more information on current trends and predictions for sea level rise, see the following:

Storm Surge

Storm surge is water that is pushed toward the shore by winds. This advancing surge combines with normal tides to create the storm tide, which can increase the effective sea level 25 feet or more. Wind driven waves are added on top of the storm surge, creating tremendous potential for extensive storm damage.

Coastal Inundation

Interested in making a local-scale inundation map or graphic to depict a future high tide or storm surge with sea level rise?

  • NOAA has created a Coastal Inundation Toolkit with information coastal inundation is and how to address it. Also see their Mapping Coastal Inundation Primer (PDF, 1.4 MB).
  • Hull’s StormSmart Coasts pilot project illustrates how three-dimensional visualizations of flood events and sea level rise can be created. The project technical report provides details on the methodology and includes images of Hull’s critical facilities under varying flooding scenarios.

Wind Risk

For projections on approximate wind speeds in your community during different categories of hurricanes, see National Weather Service’s Hurricane Preparedness website.

Coastal Hazards Characterization Atlas Data

The South Shore Coastal Hazards Characterization Atlas was developed by CZM to provide South Shore communities (between Hull and the Cape Cod Canal) with information to help review projects that are in areas vulnerable to flooding, erosion, and other coastal hazards. CZM plans to complete atlases for the remainder of the Commonwealth’s coastal regions when funding is available.

Local Knowledge

In most communities, there are areas that flood that are not mapped as flood zones on the community’s Flood Insurance Rate Maps (FIRMs). Community decisions about land use in floodplains should be based on the actual floodplain, which should be determined from all available information, including the FIRM’s data, relevant parts of the Flood Insurance Study, and your community’s experiences. During and immediately after storm events, your community can record the true (as opposed to modeled) extent of a storm. This can be done in many ways—if aerial photographs are available, these can be used, as can physically recording the extent of floodwaters (high-water marks) during the peak hours of a storm event or soon after the storm when the evidence is still visible.

Other Sources of Hazard Information

Where to Use Additional Information on Coastal Hazard Risks

As your community’s understanding of local flood and erosion risks improves, so do your chances of successfully addressing them. For example, more detailed information on areas prone to flooding, erosion, or storm damage will allow your community to better plan for development in its master plan, more efficiently prepare for emergencies in its disaster response plan, and more effectively help educate its citizens as to the real risks they face. Following are some areas where your community can use its newly found hazard information.

* Your community needs only 500 points to qualify for reduced flood insurance premiums through the Community Rating System (CRS). For more information (including how to apply for the CRS program), see our Community Rating System (CRS) primer.


Notes from the folks at CRS:

“Local governments preparing floodplain management plans or hazard mitigation plans should seek and utilize flood risk information from Federal, State and Regional agencies. For coastal communities this should include information on their shoreline change history, sea-level rise and storm surge. More credit is provided to local governments that research and use information on other risks such as high winds, subsidence and ground movement. In CRS that effort is credited under Activity 510 Floodplain Management Planning.”