Dam removals on the Boardman River improve health of fishery, ecosystem

By Nate Winkler, Biologist for Conservation Resource Alliance

Cover Photo: Michigan Out-of-Doors Editor Nick Green poses with a 22-plus-inch brown trout caught on the Boardman River below Brown Bridge in June 2020. Photo: Abraham Downer

If you stand on the Supply Road Bridge over the Boardman River and look upstream, you’d see through the cedars the confluence of the river’s north and south branches that provides its place name “the Forks.”

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A historic construction photo of Brown Bridge Dam circa 1921. Photo courtesy of the History Center of Traverse City

More creeks than otherwise, the branches merge to create the small river you’d see on the other side of the bridge, flowing north for approximately 18 river miles to Traverse City and West Grand Traverse Bay. The clear water displays the color of weak reddish-brown tea as it runs over sand, gravel and downed cedars. This water held the extirpated Michigan grayling before overfishing, deforestation, log driving and competition from non-native trout caused their demise. But more importantly, the river was a lifeline for the Odawa and Ojibwe people that lived in this region before European settlement. In fact, before Harry Boardman arrived in 1847, the river went by the name “Ottaway” in reference to the first people to live here.

The little river flows through a North Country landscape bordered by high ridges clad in oak and pine, growing in size continuously via numerous tributaries, eventually attaining suitable volume for hydroelectric power production. In the late 1800s, the construction of five dams on the mainstem was undertaken to supply electricity for Traverse City, which was transitioning from a sawmill town to a regional fruit production hub.

Concurrently, and in spite of the industrial fragmentation by the dams, the river began to heal from the wounds of the logging era to become a popular fishery for locals and visitors alike — having been stocked along the way with brook, brown and rainbow trout. Ernest Hemingway was said to have stopped to fish the river during one of his youthful junkets, and Len Halladay, a local angler from nearby Mayfield, tied a dry fly in 1922 which was first fished in the “Adams Hole” by a judge from Ohio (who went by the surname Adams). Bob Summers has built cane fly rods within a long cast of the river since the early 1970s, shipping them to anglers around the world. Kelly Galloup, western guide and fly pattern innovator, grew up fishing and snorkeling the river, essentially going to school on its trout before packing his outfit and moving to Montana. And over the years, local bait and gear fishing legends have taken some remarkable catches of trout while many youngsters (including the author’s parents) have caught their first little brookie on an angleworm or grasshopper in the numerous tributaries.

While fishing can be more important than life and death, at a certain time in Michigan’s history, dams were seen as a way of putting a river to work — a pragmatic solution for supplying energy, either for lighting bulbs or the physical energy to convert sawlogs to dimensional lumber. Less was known then about the need for aquatic organisms, especially fish, to have un-fragmented habitat, but even if much thought had been given, it likely wouldn’t have been an impediment to dam construction. Fish in rivers rely upon continuity to access different habitats for seasonal changes in foraging, spawning, and early-life requirements. Besides the effect on fish of habitat fragmentation, dams also negatively affect fish by altering the natural temperature regime by impounding the river into artificial lakes, warming water that should otherwise be very cold. On top of habitat and thermal considerations, other negative effects on fish populations and overall river health are realized through the discontinuity of sediment, nutrient and woody debris — adding up to a refutation of the contradictory term “clean energy” used by dam advocates.

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An aerial view of the Brown Bridge area shows what the river looks like restored to its natural channel. Photo courtesy of Conservation Resource Alliance.

The most contemporary dams are now gone, including Brown Bridge, Keystone, Boardman and Sabin, and they were situated in that order from near the Forks down to the lower half of the mainstem where a relatively high gradient begins at Beitner Road. However, one still stands. Keystone, Boardman and Sabin dams were in very close proximity to take advantage of this gradient which persists until the river reaches the influence of Boardman Lake, a natural lake partially within the Traverse City limits. Ranging in age from 90 to more than 100 years old, the dams had become an inefficient and unfunded liability to the owners. To explore options, a feasibility study was initiated in 2005, which culminated in a 2009 decision for removal, not entirely predicated on the anticipated environmental benefits, but that was fine with river advocates who were happy to see the river run free for any reason. Keystone Dam went out on its own accord during a 1961 flood, leaving three dams for a multi-disciplinary team composed of local, tribal, state, and federal stakeholders and officials to remove. Deconstruction took less than 10 years (2009 to 2018), but channel and riparian restoration work are ongoing as the reborn river adjusts toward equilibrium.

Because this is an article ostensibly about fish and fishing, we should consider the impact of the dam removal project on the current and future fishery. But that can’t happen first without talking about the foundation of any Michigan stream’s food web — the primary producers (photosynthetic algae) and macroinvertebrates. Macroinvertebrate monitoring in the Boardman River preceded the dam removal project and carried through past its completion; the last survey was wrapped up in 2020. What the researchers found when comparing a reference site above the dam removals to sites within or between the removals was a definite and expected negative impact during the project, but almost full recovery afterward of macroinvertebrate species diversity and density even as those data are confounded by the presence of New Zealand Mud Snails, which were discovered in the river around 2013.

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An amphibious trac-hoe works on excavating the relic channel through the former Sabin Pond. Photo Courtesy of the Conservation Resource Alliance

This is an important trend to recognize as a robust trout fishery depends on many things, and a steady supply of insects is primary among them. Coupling this with the resulting decreased water temperatures when the impoundments were removed (up to 8 degrees colder down to Boardman Lake), an already decent resident trout fishery can only get better. Additional benefits to the fishery include the creation of more complex habitats for insects and fish alike through the restoration of sediment and wood transport. The fine, organic sediments provide time-released nutrients to a nutrient-starved river and, at the same time, provide the media in which burrowing mayfly nymphs make their home and aquatic vegetation may take root. And wood not only provides habitat diversity for fish but an additional substrate on which primary producers may colonize to be preyed upon by insects.

Brook and brown trout populations have historically been found to skew in favor of the brown trout in the Boardman River, but recent fisheries data acquired by

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Michigan Out-of-Doors Editor Nick Green poses with a brown trout he caught where the impoundment from the Brown Bridge Dam used to be. Photo: Abraham Downer

MDNR below the former Brown Bridge Dam have indicated a shift. A marked increase (713% lbs./acre) in brook trout has occurred since sampling began at that location in 2010, two years before dam removal. During this same timeframe, brown trout have decreased (73.4% lbs./acre) lending evidence that this section of river is becoming more favorable for brook trout — highly likely the result of improved water and habitat quality. In addition to these quantitative data, anglers are making anecdotal reports of catching especially nice brook and brown trout not only between the dam removals but in the newly-exposed five miles of channel since project completion. Partners are continuously assessing the evaluation of habitat needs in the newly-exposed channel with an eye toward using natural materials like whole trees and logs to enhance not only the developing trout fishery but for the overall health of the river.

Gone are the days when local barber and fly tier Art Winnie and his cronies occupied a fishing shack in the cut-over slash barrens bordering the river south of Traverse City when catching trout necessitated artificial stocking. Since the 1960s, the Boardman River has been a wild trout fishery owing to its ability to heal. But there’s a ways to go before the river once again carries grayling and bears the name “Ottaway.” Both instances are on the horizon, and when that time comes, it will be momentous in terms of righting the wrongs of the past. However, as any biologist will tell you, there are no permanent victories when it comes to conservation.