CRMC releases SLAMM report

April 28, 2015, WAKEFIELD – The RI Coastal Resources Management Council and its project partners have released the Rhode Island Sea Level Affecting Marsh Migration (SLAMM) project summary report that details the findings and results of an evaluation of the response of the state’s coastal wetlands to sea level rise scenarios of one, three and five feet.

Coastal wetlands, especially tidal marshes, are one of the most susceptible ecosystems to the effects of climate change and, specifically, sea level rise. Given projected sea level rise, a considerable percentage of the state’s coastal wetlands will be lost by the end of the century unless upland areas abutting the wetlands are protected or otherwise set aside to allow inland wetland migration in response to sea level rise. Rhode Island faces the quandary of how to best quantify this response, identify potentially affected areas and future coastal wetlands, use that information to develop and apply adaptive management strategies to protect and conserve these abutting uplands, and restore degraded wetlands.

The SLAMM project - funded by the National Oceanic and Atmospheric Administration (NOAA) - during its two-year duration with in-kind services provided by the CRMC and The Nature Conservancy, assessed projected wetland response to the impacts of sea level rise out to the year 2100. The results collected from the project will assist the state and local communities in developing adaptive management strategies and practices, conservation efforts, and aid in the design of coastal wetland adaptation projects.

Project partners included The Nature Conservancy, University of Rhode Island GSO, URI Coastal Resources Center and R.I. Sea Grant, Save The Bay, Narragansett Bay National Estuarine Research Reserve, and Roger Williams University School of Law Marine Affairs. Over the two year life of the project, data was collected and analyzed for the modeling effort. The project team also engaged all 21 coastal communities to collect information used to revise initial draft maps.

The project modeling scenarios suggest that Rhode Island is expected to lose 13 percent, 52 percent, and 87 percent of coastal wetlands under one, three, and five feet of sea level rise, respectively. If these coastal marshes are allowed to migrate inland unimpeded, however, the state may have an overall net gain of wetland under the three scenarios. Several communities, however, will experience an overall net loss under the three- and five-foot scenarios. Existing development patterns greatly influence the outcomes.

The results of the project are contained in a summary report that is posted on the CRMC website in PDF file format at: http://www.crmc.ri.gov/maps/maps_slamm/20150331_RISLAMM_Summary.pdf. Static PDF maps are also available from the CRMC website at: http://www.crmc.ri.gov/maps/maps_slamm.html. Additionally, the SLAMM Geographic Information System (GIS) shape files are now posted on the RIGIS website on this page: http://www.edc.uri.edu/rigis/data/data.aspx?ISO=oceans.

“After a two-year process, the CRMC can now provide useful data to state and federal agencies and coastal communities trying to plan for the future,” said CRMC Executive Director Grover Fugate. “The scenarios will also assist in local conservation efforts to secure upland areas for future coastal wetland migration.”