Application of STORMTOOLS’ Simplified Flood Inundation Model with and without Sea Level Rise to RI Coastal Waters

The vision for STORMTOOLS is to provide access a suite of coastal planning tools (numerical models, etc.), available as a web service, that allows wide spread accessibly and applicability at high resolution for user selected coastal areas of interest. The first tool developed under this framework was a simplified flood inundation model, with and without sea level rise, for varying return periods. The methodology is based on using the water level vs return periods at a primary NOAA water level gauging station and then spatially scaling these values to generate a map. The spatial scaling was performed using predictions of high resolution storm simulations performed by NOAA using their sea, lake, and overland surges from hurricanes (SLOSH) model for various hurricane categories and by the U.S. Army Corps of Engineers (USACE) ADCIRC/WAM/STWAVE numerical hydrodynamic/wave model predictions performed as part of the north atlantic coast comprehensive study (NACCS) for synthetic tropical storms, to estimate inundation levels for varying return periods for coastal waters. The mapping methodology follows the NOAA sea level rise protocol and is applicable to any coastal region. The scaling for the RI application used Newport, RI, water levels as the reference point. The predicted flooding based on NACCS model predictions were comparable and within the range of uncertainty to that based on the SLOSH-NOAA based method. Predictions are provided for once in 25, 50, and 100 yr return periods (at the upper 95% confidence level), with sea level rises of 1, 2, 3, and 5 ft. Simulations were also performed for historical hurricane events including: 1938, Carol (1954), Bob (1991), and Sandy (2012) and nuisance flooding events with return periods of 1, 3, 5, and 10 yr. The maps are web accessible via ArcGIS and being widely used in municipal and state wide planning (http://www.beachsamp.org/resources/stormtools/).