Quantifying the increase in shoreline armoring along Michigan’s Lake Michigan coast associated with rising lake level (2014–2020)

The Great Lakes’ shorelines, particularly those of Lake Michigan, have undergone substantial transformations due to rising water levels and increased wave energy from 2014 to 2020. This period saw extensive erosion of beaches, dunes, and bluffs, prompting coastal property owners to install shoreline armoring to protect their properties. However, this protective measure often leads to unintended consequences, such as disrupted sediment transport and negative impacts on ecological communities. To quantify the armoring response to rising lake level, the extent of shoreline armoring along Michigan’s Lake Michigan coast was documented in 2021 (post-peak high water) and compared to publicly available shoreline armoring data from 2014 (pre-lake level rise). The research revealed a nearly fivefold increase in armoring from 2014 to 2021 along the coast, with the most significant increases observed in the southern section near larger towns and cities. Despite the protective intent, this widespread armoring raises concerns about its long-term effects on coastal ecosystems and geomorphology, highlighting the need for further research and informed policy decisions to balance protection needs with ecosystem function and integrity.