Maps of Trends in Narragansett Bay Coastal Wetlands

The project study area encompasses 18 municipalities that border Narragansett Bay in Rhode Island. Coastal wetland trends from the 1950s to the 1990s are presented in 10 maps organized by municipality or groups of municipalities at 1:24,000-scale. The maps depict the losses, gains, and changes in the classification of coastal wetlands and open water during the 40-year time interval. This study also focused on six demonstration sites within the study area. A composite map of the sites displays the trends in coastal wetlands and open water from 1930s to the 1950s and from the 1950s to the 1990s. These maps are intended for planning purposes only.

Aerial Photography and Wetland Classification

The source of mapped information is true color aerial photography taken at 1:12,000- and 1:40,000-scales on July 6 and August 11, 1996; and black and white aerial photography taken at 1:20,000-scale in October and November 1951 and May 1952. The trends information on the six demonstration sites originated with black and white aerial photography taken at 1:24,000-scale in December 1938 and October 1941.

Coastal and freshwater wetlands were originally classified according to the U.S. Fish and Wildlife Service’s "Classification of Wetlands and Deepwater Habitats of the United States" (Cowardin et al., 1979) and mapped according to National Wetlands Inventory standards. The marine and estuarine systems were combined and wetland classifications were grouped to simplify visual presentation of the maps. Examples of vegetated coastal wetlands include brackish marsh, Phragmites marsh, salt marsh, and salt shrub wetland. Nonvegetated coastal wetland refers to beach, panne, pool, tidal flat, and rocky shore. The target minimum mapping unit for change polygons is 0.25 acre.

Viewing and Printing Maps

All maps can be viewed on the screen as a .jpeg file that has been scaled down to fit an approximate page size of 19 in. x 22 in.

The maps can also be printed at full size (34 in. X 30 in.) or smaller using Adobe Acrobat Reader, click here to install the Adobe Reader 7.0 software for PC if needed. The wizard will guide you through the installation instructions.

Directions on how to print the maps in .pdf format.

Select the municipal maps or demonstration site map from the dropdown list below to view the .jpeg files or to print the maps from Adobe Acrobat.

Municipal Coastal Wetland Trends Maps: Losses, Gains, and Change in Coastal Wetland and Open Water from 1950s to 1990s (10 Maps)

Or

Map of Coastal Wetland Trends at Six Demonstration Sites: Losses, Gains and Change in Coastal Wetland and Open Water from 1930s to 1950s and 1950s to 1990s (Composite Map)