When the dam breaks

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The precarious state of Michigan’s river dams blasted its way into the public consciousness last May when the catastrophic failure of two dams near Midland sent torrents of water surging into nearby communities, causing millions of dollars in damage to public infrastructure and private property. Could the same thing happen in Lansing? Today’s City Pulse story on dam safety in Michigan suggests the answer, under the right circumstances, could be yes (see page 16).

Even though both Lansing dams — Moores Park and North Lansing — are structurally sound and in good working order, an historic deluge of rain still has the potential to blow them out. If the worst-case scenario happens, large swaths of land adjacent to the river banks would be inundated. Lives could be lost and many millions of dollars in property damage would be inflicted on structures within the flood zone.

Experts say that the carnage caused by a dam break could dwarf the damage caused by a typical flooding event. Eliminating that possibility by removing the dams altogether, restoring the Grand River to its natural state, has been studied and discussed for decades. We think it’s time to move forward with a comprehensive evaluation of the costs and benefits of removing one or both dams.

Lansing residents are accustomed to the wide and slow concourse of the Grand River as it eases through downtown Lansing. Altering the river’s form by removing the dams would likely cause all manner of consternation. If the North Lansing Dam was removed, the impoundment that stretches several miles to the Moores Park Dam would hold a fraction of the water volume that now fills the river from bank to bank. New real estate, heretofore submerged, would be revealed. Nature would have her way, sculpting new contours along the river banks that support enhanced riverine ecosystems. Yet the mere thought of 10 feet or more of exposed river bottom on each side of a drastically narrowed channel would likely cause conniptions among riverfront property owners — a smaller scale version of the shock felt by homeowners on Wixom Lake, a dam-created impoundment that literally disappeared overnight during the Midland catastrophe, leaving docks and boats high and dry and leaving property owners wondering if their lake would ever return.

The prospects for and implications of removing the North Lansing Dam were reviewed in a 2004 reconnaissance study by the U.S. Army Corps of Engineers that identified modification or removal of the dam as a project that would be eligible for federal funding. The dam could be replaced, the study surmised, with artificial rapids that provide enhanced habitat for fish and wildlife. New recreational opportunities would also be created for canoes and kayaks by opening the river for continuous water transit from the Moores Park Dam all the way to Grand Ledge. With some exceptions, the environmental benefits of dam removal are significant, including increased stream flow that brings improved oxygenation and water quality, accelerated sediment transport, increased habitat biodiversity, and improved fish transit and spawning. 

One of the significant downsides of removing the dam is reduced depth in the upstream river channel, which would impede the passage of larger watercraft between the Moores Park and North Lansing dams. Another concern is the release of large volumes of pent-up contaminated sediment from the river bottom, the legacy of more than a century of industrial discharges into the river, including PCBs and other noxious chemicals that would flow downstream to Lake Michigan. The uncontrolled release of such sediments can have devastating ecological consequences downstream. Removal of the North Lansing Dam would also require significant infrastructure redevelopment related to the River Trail and storm sewer systems.

An even more dramatic change in the riverscape would occur if the Moores Park Dam is removed. The massive impoundment that creates a water wonderland for recreational boaters upstream from the dam would shrink dramatically. Changes in the depth of the river likely would limit navigation to canoes, kayaks and perhaps shallow draft pontoon boats.

With the likelihood of massive federal funds becoming available for public infrastructure improvements over the next several years, the chance to secure resources for dam removal may be higher than it has ever been. But it is also likely to be a one-time opportunity: After several years of gargantuan cash outlays to counter the negative impacts of the COVID-19 pandemic, the free-flowing federal spigot will likely give way to anxious hand-wringing and legislative retrenchment in the face of massive federal deficits.

We encourage the Lansing Board of Water & Light, which owns both dams, city leaders and state environmental regulators to take a closer look at the costs and benefits of removing one or both of Lansing’s dams. Extensive public education and engagement with a myriad of stakeholders will be crucial to the success of any plan to modify or remove either of the dams. In the end, any dam removal plan will have both positive and negative consequences. Balancing those concerns and making a decision to move forward has evaded state and local policymakers for many years. Now is the time to act.

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