Document Type

Report

Department/Program

Virginia Institute of Marine Science

Publication Date

4-2004

Abstract

Utilizing geo-rectified aerial photography from 1938, 1960, 1987, and 2001, shoreline change rates were determined along the Uppards. Shoreline change rates vary but are all erosional except for areas around the north end where sand bars come and go. In the area of concern between baseline stations 4000 and 4600, the rates of erosion have increased with time. Using the rate calculated from the 1938 to 2001 shorelines for station 4000, 16 ft/yr, the 400 ft marsh isthmus width between the shoreline and Toms Gut would breach in about 25 years. This would essentially break the Uppards in two and accelerate the defragmentation of the island mass. By assuming a linear rate of shoreline change, the position of the shoreline was projected 10, 20, 30, 40, 50, and 60 years into the future based on the rates calculated between the 1938 and 2001 shorelines. The smaller oxbow tidal channel at Station 4000 would breach in about 15 years. Typically, these smaller channels fill with sand and maintain some type of shoreline continuity. However, if a “permanent” tidal channel is formed and maintains itself, island breaching, as previously discussed, may accelerate.

DOI

https://doi.org/10.21220/V5MT54

Keywords

Tangier Island, Shoreline Management, Erosion, Virginia, Geomorphic Evolution