Finding and Using Additional Information on Coastal Hazard Risks

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.

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 new Massachusetts Ocean Resource Information System (MORIS), CZM's online mapping tool.

Communities seeking more information on shoreline change and the risks that come with it can download the Heinz Center's Evaluation of Erosion Hazards, available from the Heinz Center's publications page.

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 decisions. For more information on current predictions for sea level rise, see the following:

• 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. 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 National Oceanographic and Atmospheric Administration's Sea Levels Online graphs recent trends from differnt parts of the Massachusetts coastline.
• The Internation 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.

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 a map showing estimated 100-year storm surge elevations and another showing the difference between these events and annual events along the Massachusetts shoreline, see CZM's storm surge figure (PDF, 246 KB), which was 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 format for New England's coastal communities (note: maps may be slow to download). GIS layers are also avialable. These maps and GIS layers were developed for evacuation planning purposes and represent worst case surge inundation 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 derived 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.

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