MONITORING SAND MOVEMENT BY WIND ON THE EAST SHORE OF LAKE MICHIGAN

Few studies have investigated the current processes of sediment transport within the beach-dune systems along the eastern coast of Lake Michigan. The objective of this study is to measure sediment movement by wind from October 2000 to April 2001 at a site in P.J. Hoffmaster State Park, located just south of Muskegon, MI.

Rows of Leatherman sand traps were installed at the lakeward edge of the incipient foredune, at the crest of the incipient foredune and at the base of the barrier dune. These locations were chosen to measure sand entering and leaving the incipient foredune from the beach and landward directions. In each row, four sand traps were positioned to trap sand moving from the east, west, north and south.

Erosion pins were installed in the study area to monitor elevation changes due to sand erosion and deposition. Ninety-eight pins were installed in a grid pattern that extended from the beach across the incipient foredune and over the crest of the barrier dune.

Preliminary sand trap and erosion pin results suggest that sand is entering the incipient foredune from the beach and moving beyond the crest of the dune. During the late fall, no sediments were collected in the traps located at the base of the barrier dune. Heavy snowfall in early winter halted sand movement at the site for a period of several weeks. Sediment transport resumed when portions of the beach and dune surfaces became exposed again.

Study results illustrate the dynamics of sediment movement within the beach-dune system from late fall through early spring when prevailing winds are strongest. Similar movement takes place at other coastal locations in P.J. Hoffmaster State Park and along the eastern Lake Michigan shoreline.