Regional Sediment Budget in Southwest Lake Michigan Shore

Session: Coastal Resilience in the Face of Change (1)

Yi Liu, Wisconsin Sea Grant, [email protected]
Adam Bechle, Wisconsin Sea Grant, [email protected]
Chin Wu, University of Wisconsin-Madison, [email protected]

Abstract

Regional sediment budget, a tally of sediment gains and losses, is valuable to assess change of coastal bluff environment for a selected region of coast due to anthropogenic disturbances within a defined period of time. Sources in sediment budget include longshore sediment transport into the cell, erosion of bluffs, river sediments into the coast, erosion of the beach, beach fill, and dredged material placement as from navigation channel maintenance. Sinks in sediment budget are longshore sediment transport out of the cell, accretion of the beach, dredging and mining of the beach or nearshore, and loss to a submarine canyon. In the past, less-know terms like long-term longshore sediment transport are solved through the rest of terms of better-known quantiles. In this study, we will estimate short-term storm-induced sediment transport using a state-of-the-art coupled sediment and hydrodynamic model with wave-current interactions. Accumulative effects of the sediment transport over a long term will be incorporated to develop regional sediment budget in southwest Lake Michigan shore, which will be used to guide regional sediment management. The new approach adopted here for regional sediment budget would also allow coastal managers to proactively address sustainable shore protection.