Monterey Dam decision incoming; public input sought
JANESVILLE—By March, the fate of the Monterey Dam might be known.
The state Department of Natural Resources has ruled General Motors is responsible for cleaning contaminated sediment in the Rock River upstream from the dam, and city officials have begun taking the next steps toward addressing the dam's future.
Monterey Dam, located below the Center Avenue bridge, holds back between 4 and 5 feet of water. The dam has some cracking and scour holes, leading the department to force the city to either repair the dam or remove it.
“We're required to inspect the dam every 10 years, and we've seen very little if any change in the damage in the last two inspections,” said Tim Whittaker, city stormwater engineer.
“Needless to say, the DNR still wants it fixed to make sure it doesn't get any worse,” said Paul Woodard, public works director.
The question remains: Which solution is best?
The city will ask residents during a forum next month. Members of the public will be able to look at charts and graphs and talk to officials about the costs and results of repairing or removing the dam. Inter-Fluve, a dam consulting firm the city hired in 2015, will help come up with information and displays before the meeting.
The city plans to later form an advisory committee of downtown stakeholders, local business owners, residents and one city council member. They'll meet two or three times in December and January.
“Hopefully, the advisory committee can come to some kind of consensus on what direction we should go,” Woodard said.
There will likely be a second forum in early February, and in late February or early March the committee will take its recommendation to the city council, which will make the final decision about what to do with the dam.
In the meantime, the city has plenty to learn about the consequences of repairing or removing the dam.
REPAIRING OR REMOVING
Repairing the dam wouldn't affect upstream water levels or popular fishing spots, but officials are still figuring out what the impacts would be of removing the dam.
Removing the dam would lower water levels near the dam by 4 to 5 feet. The impact on water levels would be less farther upstream. The river would drop a few inches at the Racine Street bridge, which is more than a mile upstream, Whittaker said.
Removing the dam would likely drain the shallow backwater near Monterey Stadium. The city and Inter-Fluve could convert the area into a detention pond or put in prairie plants, Woodard said.
“…If you take the dam out, what's it look like? What do you do? You have a little more exposed land now,” Woodard said.
“So that's what Inter-Fluve is going to help us with is addressing what would it look like if we took the dam out? And what can we do to improve it, keep the fishing level the same or better than it is today?” he said. “What could you do to those areas so they're an enhancement versus a detriment?”
Repairing the dam was originally projected to cost about $250,000, but bids came back at twice that cost. Removing the dam and doing any upkeep to the area could cost even more, officials said.
“It's not just a removal cost. It's removal and shoreline restoration cost,” Whittaker said.
The city applied for a grant to help pay for repairing the dam but was denied. Monterey Dam is a low-hazard dam, which means there's no significant safety issues downstream if the dam continued to deteriorate, which is part of the reason the grant was denied, Whittaker said.
“But there's more grant opportunities for removal of the dam because the DNR would like to see the dams removed statewide ... so you're more likely to get funding for removal than you are repair,” Woodard said.
It's the owner's decision whether to repair or remove a dam, said Rob Davis, DNR water management engineer.
Still, dams that are no longer serving a specific purpose, such as the Monterey Dam, aren't the best for resources such as fisheries, he said.
The department approves 15 to 20 grants a year for dam repair or removal. The vast majority are for repair, but removing a dam “scores better” during the competitive grant scoring process, Davis said.
“The reason for that is because you're reducing liability. That's one of the point categories,” he said.
If the city council decides to repair the dam, the work could be done as soon as the city had the money for it, which would probably be 2018.
Removing it would be more complicated. There's no timeline for when GM is supposed to have the contaminated sediment cleaned up, and officials aren't sure if the dam could be removed before the sediment is cleared, Woodard said.
The department originally gave the city a deadline to address the dam, but the department granted an extension when the contamination issue surfaced. There's no deadline to fix the dam now, officials said.
“Apparently, the DNR doesn't penalize a community that's working toward resolution on an issue,” Woodard said. “We're working cooperatively with the DNR. They know we're trying to solve this issue and trying to coordinate the community's desires versus GM's sediment issue.”