Although the official start to summer is still more than a week away, Michiganders have officially shifted into beach mode. But after a spring filled with heavy rains and shifting water levels, what should people expect when they visit the Great Lakes shorelines this summer?
Assistant Professor Ethan Theuerkauf, a coastal geomorphologist at Michigan State University’s Department of Geography, Environment and Spatial Sciences, provides the state of Michigan’s shorelines.
Theuerkauf and his team lead the Coastal Processes and Geomorphology Lab. Here, he breaks down what’s happening where the land meets the water — and how lakeshore residents can use this summer’s calmer conditions to prepare for the future.
Where should we expect lake levels to be this summer?
With the spring rain, we absolutely saw lake levels rise throughout the Great Lakes basin. Along lakes Michigan and Huron, water levels rose about a foot between March and April. In fact, it is the same amount of lake level rise that we typically see from winter to the peak of summer.
However, May was quite dry, so if that pattern continues into the summer, it is unlikely that we will see additional major increases in lake levels. Currently, water levels along lakes Superior, Michigan, Huron and Erie are all right at average levels, which is slightly higher than last summer but should still provide great beach and boating conditions.
Based on the current trajectory, is this a ‘recovery summer’ for beaches?
I would anticipate that in locations where sand is abundant in the nearshore, beaches will continue to recover this summer. I do not anticipate that major erosion will occur over the coming months, given average water level conditions and a typical absence of storms during the summer.
How can beachgoers contribute to coastal monitoring this summer?
We are always happy to see pictures that people have taken of the same spot over multiple years. For instance, if you always go to the same beach in Saugatuck or Ludington, snap a shot from the exact location where you took a picture in a previous year and send it to my lab’s website. Seeing these repeat photographs helps us understand the varied responses of Michigan’s beaches.
Do you anticipate high shoreline armoring along Lake Michigan this summer?
This summer, I do not anticipate that there will be an increase in armoring, which involves building physical structures such as seawalls, riprap and bulkheads to protect coastal property from erosion and storm surges. However, since lake levels are at average conditions and we are not anticipating extensive erosion, now would be a good time for lakeshore property owners to think proactively about how they can prepare for the next lake level rise.
Actions such as moving infrastructure away from the shoreline, planting dune grass and promoting natural vegetation recolonization are all great things to do during periods of lower lake levels to prepare for future high water. We do not know exactly when lake levels will get as high as they were in 2020, but we do know that they will eventually get back there — that is the natural cycle of lake levels.
What consequences should people be aware of with shoreline armoring?
While armoring can slow erosion in the short term, it does so with consequences for both downdrift property owners and beach recovery. In many cases, armoring can exacerbate erosion issues on adjacent property. Armoring also makes it much harder to recover beaches during periods of low or average lake levels, like we are currently experiencing.
There are numerous beaches throughout the Michigan coast that have struggled to recover after high lake levels because they are located in areas with extensive armoring, which amplifies sand starvation issues. To recover a beach, you must be able to source sand into the shallow nearshore and then have calm wave conditions push it back onto the beach. Armoring often pushes sand out of this “sweet spot” and into deeper water.
How do water level predictions for Great Lakes differ from oceans?
We saw a peak this spring of how dynamic and unpredictable Great Lakes water levels can be. This is one of the unique traits of our Great Lakes system and is fundamentally different from how the oceans behave with sea levels.
Our lake levels are inherently linked to regional weather patterns. When it is dry, lake levels go down, and when it is wet, they go up. Since we cannot predict the weather months to years into the future, we cannot know what the lake level will be next year or the following year. This makes it tough for coastal managers, as they have to deal with constant changes along the lakeshore.
Our research aims to broaden our understanding of the range of changes that a community may have to respond to and then work with those communities to educate them on how to address coastal changes without causing additional harm.
What research are you conducting this summer?
We are working on a variety of projects this summer throughout Michigan’s beaches and wetlands. One project we are currently excited about is getting out in the field to map coastal erosion using drones at popular recreation sites, including Indiana Dunes National Park, Sleeping Bear Dunes National Lakeshore and Pictured Rocks National Lakeshore. Spots within these parks are experiencing rapid rates of erosion and sediment movement, and our drone imagery can help the National Park Service make better decisions about where to place infrastructure and what types of management strategies should be pursued (e.g., plantings, fencing, etc.).
We are also continuing our work with Michigan’s Coastal Management Program within the Department of Environment, Great Lakes and Energy to understand beach recovery following high lake levels. We have been mapping some sites since 2021 and will get out again this summer to document the state of those beaches. This record of change helps us understand the conditions that promote or inhibit recovery and allows us to refine our predictive models of whether a given beach will recover after a high lake level.
Finally, we will be collecting sediment cores and elevation data in the wetlands of Saginaw Bay to better understand carbon storage in Great Lakes coastal wetlands, as well as what environmental conditions promote wetland plants to recover after high lake levels.
