Stabilizing Concordia University’s Bluff

Wisconsin, Ozaukee County, Mequon

Concordia University, located in an affluent suburb just a few miles north of Milwaukee, Wisconsin, is situated along the shore of Lake Michigan. Though the institution's long history dates back to the late 1800s, it was not moved to its current location until 1982 (" Concordia University - Our History" ). Touting nearly 192 acres of land and 2,700 feet of shoreline, the campus itself sits atop a nearly 130 foot high bluff (" Shoreline Stabilization Saves Crumbling Coastline at Concordia University Wisconsin "). Since its relocation, the University watched as the bluff eroded rapidly with the bluff edge creeping nearly a foot closer each year. The bluff was literally washing away – 20,000 tons of sediment per year or approximately 5-acres of land between 1982 and 2005, threatening the safety of the campus, students, and faculty.

Recognizing that current conditions were not sustainable, University leaders decided to take action, hiring an engineering firm to stabilize the bluff. After receiving approval from the U.S. Army Corps of Engineers and the Wisconsin Department of Natural Resources in 2005, they broke ground on what has been named one of the top five civil engineering projects in 2010 (" American Society of Civil Engineers - Honors and Awards "). To help slow erosion rates, the consulting engineers sought to "de-water" a 2,800 foot long stretch of the bluff by building in drains to collect water and ultimately reduce the pressure placed on the rapidly eroding soils. In addition, they also sought to stabilize the bluff by constructing artificial perched and coastal wetlands, decreasing the slope of the bluff to a stable incline, revegetating exposed soils on the bluff face, and placing revetments along the shoreline to protect the bluff toe from persistent wave action (" Lake Michigan Coastal Erosion and Bluff Failures "). Recognizing that current conditions were not sustainable, University leaders decided to take action.

In total, this remarkable 12 million dollar project took eight years to plan, fund, and execute, and used a staggering 100,000 tons of rock, stone and vegetation in the process. Although the stabilization project has not halted erosion entirely, it has significantly reduced the rate at which it occurs on Concordia's bluff. As with any coastal construction project, unintended consequences are possible and have been noted by neighboring properties downstream of Concordia's stabilization project (" Concordia Being Sued Over Bluff Stabilization Project "). By armoring the shore, sediment transport budgets have been altered, preventing some areas from being nourished and increasing erosion rates there as a result ( Lin and Wu, 2014 ). These challenges are not limited to Mequon, Wisconsin. Bluff erosion and the challenges associated with its management continue to be problematic for many communities in the Great Lakes Region.

In an effort to prevent others from having to face these challenges in the future, Ozaukee County has developed a zoning ordinance which prohibits development within unsafe distances from the edge of the bluff (" Shoreland and Floodplain Zoning Ordinance "). However, there is no publicly available documentation of the process used to determine this setback requirement. There is a distinct need for the development and implementation of an easily replicable science-based methodology for determining safe coastal setback requirements in the Great Lakes basin. If determined, such practices could help to inform future planning and policy-making efforts, and ensure that other coastal communities are designed to be resilient to bluff erosion.

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