Photo: R. Hancock Sea Levels Affecting Marshes Model Using SLAMM to Conserve Rhode Island Coastal Wetlands Coastal Resources Management Council Coastal Education Series May 27, 2014 James Boyd, CRMC Coastal Policy Analyst
Rhode Island has lost 53% of its historic salt marshes over the last two centuries* due to man-made alterations (ditching and filling) resulting in a loss of about 4000 acres statewide * Bromberg and Bertness, 2005
STB’s 10 years of restoration monitoring has shown that conditions can change rapidly in tidally restricted marshes Recently, similar degraded conditions have been observed in marshes with no tidal restrictions 2010 Source: Save The Bay
Marsh Migration Source: W. Ferguson, Save The Bay
Marsh Migration Source: J. Boyd 05/15/14
HEIGHT NOW Adapted from: sltrends_station.shtml?stnid= %20Newport,%20RI Boothroyd 2013 Rate of Rise /-.7 inch/100 yr
USACE and NOAA SLR Curves
Sea Level Affecting Marshes Model (SLAMM) North Kingstown Pilot Project (2011)
All 21 Coastal Communities Completed Region 1 Region 2 Region 3
SLAMM Project Goals 1.Develop marsh migration modeling results (maps) 2.Identify existing vulnerable wetlands 3.Identify impacted upland parcels – opportunities and challenges 4.Develop new CRMC coastal program adaptive strategies, policies and standards (Beach SAMP) 5.Increase local capacity to proactively incorporate sea level rise for wetlands (e.g., comprehensive plans, zoning codes, conservation, etc.)
Sea Level Affecting Marshes Model (SLAMM) Simulates the dominant processes involved in wetland conversions during long term sea level rise Applied and improved since 1985 Used throughout the world
Sea Level Affecting Marshes Model
Topography is the basis for Model
Modeling – Current Conditions
Model Results – 1’ SLR
Model Results – 3’ SLR
Model Results – 5’ SLR
SLAMM Predicted Statewide Salt Marsh Changes due to Sea Level Rise SLR1 Ft.3 Ft.5 Ft. Loss (Acres) Gain (Acres) Net Change (Acres) ½ of Current Salt Marshes
SLAMM Project is part of the Beach SAMP