A Small Dam Removal Project with a Big Impact

by Kristin Thomas, Michigan TU Aquatic Ecologist

Murray Dam was a small dam on Hunt Creek in the Au Sable watershed. Hunt Creek flows into West Branch Big Creek near Luzerne. Both are coldwater streams, and Hunt Creek is known primarily as a brook trout system. The removal of Murray Dam was a small project with big rewards. The before (shown above) and after (shown below) photos tell the story perfectly. It was one of those rare projects that provided immediate, immense satisfaction. The benefits are apparent almost instantly and continue to increase over time, reaching far beyond aesthetics. This is only one aspect that made this an incredibly fun and rewarding project. The thoughtful involvement of the landowners, the benefits to the watershed and fishery, and the unique beauty of the site all combined to make this a favorite project for the Michigan TU staff, a project that makes one so grateful for their job.

The dam on Hunt Creek was located upstream of where the stream flows into West Branch. Landowners had long valued the dam and reservoir for recreation and beauty because they had been there since they purchased the property. Traditions passed down from generation to generation are so special. The presence of the pond was one of those traditions that was hard to let go of. The family members had fly-fished the pond and caught some fine trout in the past, and they enjoyed all the wildlife the pond supported.

The landowners are an incredible family committed to protecting and improving their beautiful property. So, upon noticing the pond was filling in with sediment, they knew they needed to think about what would come next. While seeing changes in their ability to use the pond as it filled in, they were also worried about the impacts the dam and impoundment may have on Hunt Creek and West Branch. They reached out to Michigan TU for help identifying effects and evaluating dam removal or modification options.

The first step in the evaluation process was to collect temperature data around the dam to document if there were impacts to Hunt Creek or West Branch. In 2018, continuous temperature loggers were placed about a mile upstream of the dam at a road crossing, immediately downstream of the dam, and West Branch upstream and downstream of Hunt Creek.

The recorded temperatures left little doubt about the dam and the successional reservoir’s impact on water temperature. The mean July temperature upstream of the dam was 63°F, while immediately downstream in Hunt Creek, it was 68°F. However, the temperature data was more alarming on a daily basis. The average daily jump in temperature from upstream to downstream was 10°F with a maximum point of 26°F. That’s a huge jump in temperature.

The temperature impact was also evident in the West Branch, with an average daily increase in temperature downstream of Hunt Creek of 3°F and a maximum point increase of 14°F. The temperature increases created stressful conditions for coldwater fish because Hunt Creek should function as a coldwater refuge during temperature stress. The landowners and funders alike were convinced that the dam’s thermal impacts were severe and that action should be taken.

The landowners decided as a family that pursuing dam removal was the right thing to do. We can’t stress enough how applaudable that decision was. The family had to balance lifetimes of wonderful memories tied to the dam

and reservoir with knowledge of its impacts and longterm prospects of continued maintenance of the dam and confront change to the property that is dear to them. The decision to pursue removal was not reached lightly. The prospect of losing the pond where the family learned to fly fish and trumpeter swans nested during a triumphant recovery story was overwhelming and scary. The family worried that losing the pond would degrade the quality of the property both in terms of economics and natural resources.

The Murray family has incredible gratitude for the role Michigan TU Executive Director Dr. Bryan Burroughs played in this decision process: “Without Bryan carefully and thoughtfully explaining to our family what was happening to the pond, the process of dam removal, and how removal would support the fishery, we as a family would not have come together to support dam removal. We are also grateful for the partnership we had with Michigan TU, and the funding agencies, which patiently helped guide us through the process and made the project as easy as possible.”

That type of hard decision will play out so many times in the coming years across the thousands of dams in Michigan. Nonetheless, the Murray family showed courage, foresight, and conservation ethic in making the proactive decision to remove their dam. They also put their trust in Michigan TU to ensure it would be done well and for the better. With their blessing, Michigan TU began seeking funding for dam removal. Grantors saw value in this project; funds were awarded from the Michigan DNR Fisheries Habitat Grant Program and the USFWS Fish Passage Program. Once funding was acquired, the fun work could begin!

The process for removal included the pond’s drawdown through the removal of 2.5 feet of flashboards, then the dam’s elimination, and the associated 1.5 feet of underlying concrete. The drawdown of the impoundment occurred in 2021, laying the groundwork for dam removal in 2022. The landowners removed the flashboards in a controlled manner to ensure excessive sediment was not sent downstream. Due to the deposit amount, the stream had already started channeling in the pond before the drawdown. Consequently, after the drawdown, a channel quickly appeared, and vegetation of the old bottomlands began.

While the aesthetics changed in the transition from pond to stream, the beauty was not lost. The valley Hunt Creek flows through is indescribably beautiful. An incredible example of northern Michigan beauty is a meandering stream in a valley flanked with pines and tamaracks. It is awe-inspiring at all times, but the beauty is unmatched in the fall with golden tamaracks. The Murray family expressed this change well. “We were fearful that losing the pond would lead to a loss in the beauty and natural wonder of the property when in fact, it seems to have added value creating a new type of beauty and habitat for a new set of birds, amphibians, and reptiles. Value has been added, not lost.”

Dam removal was completed in June 2022. The concrete was removed, the stream channel was widened through the old dam site, and a footbridge was built to maintain access to the entire property. The removal process went well, and Hunt Creek began to adjust to the change in elevation that came with removing the final 1.5 feet of concrete. Minutes after the last pieces of bottom concrete were taken out, a brook trout swam through the dam site, directly underneath the still overhanging shovel of the excavator. Talk about immediate satisfaction—one of the coolest things any of us on site have experienced! While the elevation of the stream did immediately begin to adjust with dam removal, the process quickly slowed as the flowing water struggled to move or erode through the sticky peat found in the new stream channel from decades of plant decomposition in the pond.

There is still work to be done in the new channel in 2023. The substrate in the old pond is a very sticky peat that does not yield easily to the water flow. It is amazing how well it sticks together in the face of flowing water; nature never ceases to amaze. What this means for the river is that the 1.5 feet of the head from the dam has yet to spread as far upstream through the channel as ideal. There is still a bit of disruption to grade moving upstream through the old impoundment. Dam removal’s primary objective is to restore gradient or stream slope with more mobile substrate grade is restored quickly.

This winter, a plan will be developed to restore the channel fully. That will include adding woody habitat, as there is not much currently, and distributing the gradient upstream to truly reconnect the stream. Temperature loggers will also be placed in 2023 to document changes in the temperature regime of the system. We expect to see more consistent temperatures throughout. While there is still some work to be done, the current benefits to both Hunt Creek and West Branch cannot be overstated.

Another aspect of this project that makes it outstanding is its cost-effectiveness or its return on investment (ROI). We know that many hundreds of dam removals are needed in coming years, and funds to accomplish this work are finite. Michigan TU thinks about the ROI of projects to ensure that limited resources achieve the most good, and many projects need to get done. The return for this project includes four miles of stream open and accessible to fish, ten degrees colder summer water temperatures in Hunt Creek, and three degrees colder water for West Branch. That creates significant thermal refugia for hotter summers and moves West Branch from marginal to more ideal conditions. When completed, this project will likely cost less than $50,000. That’s an incredible amount of value for the investment. While this project was brought to our attention by the owners, it is up to us to find more projects. That work has started and will continue.

This project cannot be discussed without expressing incredible gratitude to the property’s family. They have consistently put the natural resources first throughout the project and have been a joy to work with. Thank you, Murray family, for the generous and selfless way you have prioritized the restoration of Hunt Creek. Thanks, also, to those who funded this work; the Michigan DNR Fisheries Habitat Grant Program and the US Fish and Wildlife Service Fish Passage Program. Without their financial assistance, this project would not have happened. Both entities immediately recognized the value of this project and awarded the funds to implement it, allowing Michigan TU to put more time into making it happen.

In case you, your family, or a friend own a dam in a coldwater watershed, please do not hesitate to contact Michigan TU for help evaluating options and considering dam removal. Trout might be waiting for the next big success story.