North-Central Section - 54th Annual Meeting - 2020

Paper No. 5-10
Presentation Time: 11:20 AM

THE CONNECTIONS BETWEEN LITTORAL DRIFT DISTURBANCE, LAKE LEVEL, SHORELINE BEHAVIOR AND COASTAL RESILIENCE ALONG THE SOUTHERN SHORELINE OF LAKE MICHIGAN, NORTHWEST INDIANA


ARGYILAN, Erin P., Dept. of Geosciences, Indiana University Northwest, 3400 W. Broadway, Gary, IN 46408

The southern shore of Lake Michigan represented the zone of net littoral drift convergence for the basin throughout the Holocene. The Calumet lacustrine plain is the dominant geomorphic area along the Indiana coast and consists of a series of high parabolic dunes in the east that fans out to an extensive strandplain of low-relief beach ridges and wetland complexes to the west. Major harbor structures have redistributed sediment transport into three smaller drift cells. Meanwhile industrialization and urbanization continue to impact sediment transport in the nearshore and onshore zones. While the approximately 45 mile shoreline of Indiana experiences the same fluctuations in water level, differences in shoreline behavior and geomorphology now exist within individual drift cells as a result of shifts in sediment supply. As water levels in Lake Michigan-Huron surged from the historical low of 2013 to a record high in 2020, it elucidated important issues of land use planning and coastal management that stem from local variability in sediment supply and shoreline behavior. Local issues that include social trails, dune migration, dune collapse, and property loss or damage can all be best understood and addressed from the perspective of shoreline behavior and coastal geomorphology. Analyses of aerial photography, LiDAR data, and drone imagery highlight how coastal geomorphology varies along the southern shoreline of Lake Michigan and provides the framework for understanding coastal vulnerability and resilience for planning and implementing coastal management.