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:

• The National Oceanographic and Atmospheric Administration’s Sea Levels Online graphs recent trends from different parts of the Massachusetts coastline.
• The South Shore Coastal Hazards Characterization Atlas Description of Variables (PDF, 1.05 MB) has detailed information for the Massachusetts coastline on pages 19-20.
• The U.S. Global Change Research Program Online Resource Library provides access to data and information on climate change research, adaptation/mitigation strategies and technologies, and global change-related educational resources. They have a section on climate assessment with some information in it.
• The U.S. Environmental Protection Agency is generally accepted as an authority on sea level rise trends. See their Sea Level Rise Reports and Coastal Zones and Sea Level Rise pages.
• The International Panel on Climate Change (IPCC) has extensive information on sea level rise available on their frequently updated web site.
• This Union of Concerned Scientists report (PDF, 540 KB) provides specific predictions on the effects of sea level rise in Massachusetts.
• Coastal communities can find general suggestions for means of adapting to rising sea levels and climate change in Preparing for Climate Change: A Guidebook for Local, Regional and State Governments.
• The Florida Institute of Technology has assembled a new library of sea level and coastal climate adaptation.

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.

• For maps showing your community’s estimated storm surge risk, see the CZM’s storm surge maps (PDF, 246 KB), which were produced as a part of the The South Shore Coastal Hazards Characterization Atlas Description of Variables (PDF, 1.05 MB).
• The New England District of the U.S. Army Corps of Engineers has created hurricane surge inundation maps in PDF form for New England’s coastal communities (note: maps may be slow to download). GIS layers are also available.

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

• The NOAA Coastal Service Center’s Digital Coasts website, which couples data and tools together to help inform coastal decision makers. See their Digital Coasts in Action page for examples on how some communities (including several in the region) are using the site.
• The iCAT Damage Estimator is a web tool that shows storms from 1900 to the present with damage projections for how much damage each storm would cause if it were to hit today (read our post on the iCAT Damage Estimator).

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.

• Planning
  • Creating a multi-hazard mitigation plan
  • Creating a community master plan
  • Creating risk mitigation strategies
  • Creating a multi-objective management plan
• Regulations and Development Standards
  • Passing strict zoning ordinances and regulations
  • Considering potential future conditions when siting new development
  • Keeping public infrastructure outside of hazard-prone areas
  • Creating permanent no-build areas
• Infrastructure
  • Protecting critical access routes
  • Keeping roads and utilities out of damage-prone areas
  • Regularly inventorying hazard risk to all public property
  • Siting critical facilities out of harm’s way
• Emergency Services
  • Creating a disaster response plan
  • Improving disaster response coordination
• Education and Outreach
  • Raising general hazard awareness

* 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.”