Dam removals can restore Fox, Des Plaines rivers, experts say
An upgraded ecosystem. Better water quality. Safer and improved recreational activities.
Good reasons abound for removing the state's run-of-river dams, including 10 along the Fox River and the two remaining along the Des Plaines River, experts say. Most are more than a century old, have been deteriorating for years and no longer serve their intended purposes.
But tearing down these structures is easier said than done, says Steve Pescitelli, a fish biologist with the Illinois Department of Natural Resources. It's an issue of cost, manpower, and in some cases, resistance from community members.
"Our goal is just to try to remove as many as we can and extend these sections of free-flowing stream, which will make them more resilient," he said. "It's the best thing you can do for a river."
Most dams were built in the late 1800s and early 1900s to control water levels or to generate hydroelectric power for river towns. Some also served sanitary waste, agriculture and transportation purposes, said Eric Otto, civil engineer at the Forest Preserves of Cook County.
But most of them have become obsolete and are now causing more harm than good. Not only do they pose safety threats for recreational users of the waterways, but they also degrade a river's water quality and aquatic habitat.
"At this point, when they're beyond their original intended purposes, they're hazards and ecological impediments," Otto said.
Dams create still pools of water upstream, similar to lakes, that cause oxygen levels to fluctuate and an overabundance of algae, according to a study of Illinois streams that Pescitelli co-authored.
Dams also create a barrier that prohibits the free movement of fish and aquatic life. When the Hofmann Dam in Riverside was removed from the Des Plaines River in 2012, for example, the number of fish found upstream doubled, and the number of species jumped from six to 29 within a matter of weeks.
"What we found was that the free-flowing areas downstream and in between dams were much more healthy than the area behind dams," Pescitelli said.
A 2012 state dam removal initiative has funded 11 projects to date, said Rick Gosch, manager of the division of capital programs with the IDNR's Office of Water Resources, and design plans are nearly complete for seven other dams.
However, all progress stopped two years ago when state money dried up. Each project can cost anywhere from hundreds of thousands of dollars to several million, depending on size and complexity of the dam, he said.
Before the state budget crisis, significant progress was being made on the Des Plaines River, where only two Cook County dams remain, Otto said. Those projects -- the Touhy Avenue Dam near Park Ridge and Dam No. 4 near Rosemont -- are expected to be in the homestretch once funding is made available, he said.
Removing those structures would restore more than 100 miles of free-flowing stream, Pescitelli said, "which would be pretty remarkable and actually of national significance."
Other projects on the horizon include two on the North Branch of the Chicago River and three on the downstate Vermilion River.
In the past two years, though, Lake County Forest Preserve District leaders have taken matters into their own hands by removing the two Des Plaines River dams left in their jurisdiction, said Jim Anderson, director of natural resources. When the state froze a $750,000 grant intended for the projects in MacArthur Woods near Libertyville and Captain Daniel Wright Woods near Mettawa, he said, the forest district fronted the costs.
"It's a really important, ecological and aesthetic project that we're glad to have done," he said.
Fox still clogged
Of the 15 dams built on the 115-mile-long section of the Fox River that runs through Illinois, only two have been removed to date. Those projects in Batavia and Aurora were completed more than a decade ago.
All but one of the dams that remain are between McHenry and Yorkville. With so many structures and dam pools only towns apart, the waterway serves more as a lake than a river, said Cindy Skrukrud, Sierra Club clean water program director.
A coalition called the Fox River Study Group was formed in the early 2000s to develop a plan for improving water quality. One of the most effective solutions? Removing dams, said Gary Swick, a study group member and president of Friends of the Fox River.
"What we're trying to do is restore the river to its original character," he said.
If state money becomes available, dams in Carpentersville and North Aurora might head the Fox's removal list. And Skrukrud, also chairwoman of the Fox River Study Group, said the group might serve as a local sponsor to help fund the completion of a study to determine a plan for the rest of the dams. They'd also try to push forward the two projects that have already made some headway.
How much those efforts would cost, and where the money would come from, has yet to be determined.
When and if the state starts removal projects on the Fox, IDNR's Gosch said, each dam has its own set of specialized circumstances that must be considered before it's torn down.
For example, the Algonquin and Stratton dams in McHenry County likely would not be candidates for removal, he said, because they regulate water levels in the river and the Chain O' Lakes.
Dam pools allow recreational boats to move in all directions, Gosch said. If they're removed, recreational users would be restricted to moving in two directions: with or against the river's natural current.
While that may be beneficial for canoers, kayakers and fishermen, Swick said, it would significantly change the use of the river in communities like St. Charles, where paddle boating, power boating and other related activities rely on deeper and more stagnant sections of the waterway.
A local task force has been developing a plan to remove the dam and rebuild a similar structure a quarter-mile north. Chairman John Rabchuk said it would mimic the river's natural rapids, be more eco-friendly and provide more recreational opportunities in the city's downtown.
In Batavia, removing the city's second and only remaining dam would drain the Depot Pond, a key feature of its downtown, City Administrator Laura Newman said. The issue caused contentious debates more than a decade ago between environmentalists and community members who didn't want the downtown's landscape to change.
With the structure continuing to deteriorate, discussions about tearing it down picked up again last fall, Newman said. No action will be taken until state funding becomes available, she said, but the city will soon have to decide whether to remove the dam, and if so, whether to pay more to keep the pond filled.
It's not uncommon for dam removal to be an emotional issue, Friends of the Fox's Swick said. Residents often view the dams as a fixture of their communities and are fearful of what will happen, both aesthetically and recreationally, without them, he said.
Their concerns should be seriously considered, he said, but communities should be looking at the bigger environmental picture rather than the recreational perks.
"For me, personally, restoring the river to its natural integrity is the No. 1 priority, and to think that we want to continue to degrade the habitat for a single use is questionable," Swick said. "I'm just hopeful that in my lifetime, I can see a lot of the Fox River restored to its free-flowing character."