Five years flow past dam site

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November marked five years since St. Johns Dam was removed from the Sandusky River at the CR 6 crossing. And the river's water quality has responded well to the free-flowing state.

"Five years flew by," said Bob Vargo, manager of the Sandusky and Maumee Scenic Rivers program, part of the Ohio Department of Natural Resources Division of Natural Areas and Preserves.

"The ultimate goal was to improve water quality for the Sandusky River," he said.

And that purpose has been accomplished.

"We went basically from a cesspool situation to a pristine situation," Vargo said.

Before the dam was removed Nov. 17, 2003, water was impounded about 8 1/2 miles upstream and the water quality was impaired.

"It went all the way up to exceptional warm water habitat in less than two years," he said. "That's the best water quality you can get.

"We were all surprised how quickly the river recovered on its own," he said. "Mother Nature did it on her own."

Vargo said the idea for removal came about after a study determined the dam was in need of repair or removal. At the time it was owned by Ohio American Water Co.

"It was supposed to supply water to Tiffin in case of emergency," he said.

But it was determined there was not enough water behind the dam to provide a good emergency supply and the repair cost was too high.

"It was in need of repair and the company was under orders to fix it or get rid of it," Vargo said. "It was cheaper to get rid of it."

The company donated the dam and a small amount of property on either side of the river to the state, and the Ohio Department of Transportation took care of the $77,970 cost of removal to earn some of the stream mitigation credits it needed for the US 30 improvement project.

ODOT was required to monitor the river for five years, which was completed this summer. Researchers were looking for changes in physical characteristics, such as regrowth of vegetation on exposed river banks.

The actual removal was completed in 2 1/2 hours.

"It was just a matter of time before that dam would have breached and collapsed," he said. "It was in pretty bad shape."

Although he couldn't find a history of the dam at the time, Vargo said the structure reportedly was built in the 1930s.

"The contractors bid on not a lot of information," he said.

"We did the pre-removal research in the summer, which delayed the removal," he said. "Research on dam removal had previously involved only fish. There was nothing as intense as this research that followed these parameters and the various aspects of it."

Vargo said the original plan was to study the river around the dam before removal and continue the study for five years afterwards.

"The goal behind this was to compile everybody's research and produce a document and have it published," Vargo said. "It ended up being only two years. After that, based on our findings, EPA came out once or twice to do some spot checking."

In addition to the rapid recovery, Vargo said a lack of funding contributed to the early termination of the study.

"It might be revisited in another five years," he said, depending on funding and staffing levels at that time.

During the two years following the removal, several studies were conducted.

One was a macroinvertebrate - or water insect - sampling by Ken Krieger of Heidelberg College.

ODNR's Division of Geological Survey studied the river's substrate using global positioning system technology.

"They ended up transferring those points to aerial photos," Vargo said.

That provided information about the riffles, runs and pools. The information can be compared with information from before the dam to determine the changes. And later studies can chart how the river changes through the years.

The Division of Wildlife investigated the types of fish found in the area through an electro-shocking study.

Vargo said people who fish the river have reported better catches.

"Smallmouth bass and rock bass have increased, but their habitat has increased, too," he said.

Four new riffle areas were exposed after the dam was removed. Insects colonized those riffles and fish soon followed.

In another study, two professors from Ohio State University studies mussels.

Still another aspect of research was checking the water levels in various drinking water wells before and after the removal.

"We looked at that because of cautions I had read," he said. "Basically, the static water levels dropped two inches from the dam coming out, which is negligible."

Another study looked at the effect of removing the dam on the river banks.

"He had an elaborate setup in the canoe," Vargo said.

It contained a GPS unit and Doppler radar equipment, as well as meters to accurately record fine sediment movement.

"They were looking at sediment transport because with dam coming out, the river is free flowing," he said. "Things would get scoured during a storm event and then it would get deposited somewhere. Is one bank building up and one bank being scoured?"

Although the study results haven't been compiled into one document, Vargo said the results of some studies have been published individually and others have been presented at conferences.

During the past few years, he has been contacted by graduate students and researchers in other states studying the effects of dam removal.

"You want it to be disseminated and to be used," he said.

Vargo said several hearings took place before the removal and people were divided about wanting the dam to be repaired or removed.

"I still run into occasional opposition," he said. "But it's not as mean-spirited as it was back then."

Vargo said he understood the opposition.

"It's change," he said. "Humans don't like change. Over time, you get accustomed to it."

Overall, he said the river is cleaner, which is good for the environment.

"I know the fishermen are happy," he said. "I think the canoeing is better because you don't have to constantly paddle. Most of the time you've got some current. The water kind of picks up speed. We joke that's the rapids of the Sandusky."

He said he still sees small boats in the river when the water is high enough.

"Everything's dependent on the water level," he said. "It's like snow skiing. If you've got a lot of snow, it's nice. If you got a couple inches you aren't doing too well."

The next dam removal scheduled for the Sandusky River is Ballville Dam near Fremont in 2011 or 2012. The city of Fremont uses water behind the dam, but the city is constructing a reservoir to replace it.