A series of 15 digital flood-inundation shapefiles and grids were developed for a 10.2 mile reach of the Pawtuxet River in West Warwick, Warwick, and Cranston, Rhode Island by the U.S. Geological Survey in cooperation with Rhode Island Emergency Management Agency and U.S. Army Corps of Engineers. The coverage of the maps extends from downstream of Natick Pond Dam near State Route 33/Providence Street bridge in West Warwick, to the river’s mouth at Pawtuxet Cove (Broad Street bridge) on the border between Cranston and Warwick, Rhode Island.
A hydraulic model was used to compute water surface profiles for 15 flood stages at 1-foot (ft) intervals referenced to the streamgage and ranging from 8.0 feet (ft; 15.2 ft North American Vertical Datum of 1988), which is the National Weather Service Advance Hydrologic Prediction Service’s flood action stage, to 22.0 ft (29.2 ft North American Vertical Datum of 1988), which is the maximum rated stage at the streamgage and exceeds the National Weather Service Advance Hydrologic Prediction Service’s major flood stage of 13.0 ft. The simulated water-surface profiles were combined with a Geographic Information System digital elevation model derived from light detection and ranging (lidar) data with a 1.0-ft vertical accuracy to create flood inundation maps. The flood inundation maps depict estimates of the areal extent and depth of flooding corresponding to selected 15 flood stages at the U.S. Geological Survey Pawtuxet River at Cranston, Rhode Island streamgage (01116500). First posted - March 7, 2018 (available from author) Revised - September 17, 2018 (ver. 1.1)