Temporary coffer dam to be installed Saturday

By Jim Newell

Review Editor

The Paint Creek dam needs to undergo immediate assessment and repairs to fix a “depression” below the spillway that allows water to flow from Lake Orion into the creek unchecked.

The public is not in any immediate danger, nor is the dam in immediate danger of failing or Paint Creek of flooding, said village and state officials on Friday morning.

The dam – located under the M-24 overpass just north of where Broadway Street/M-24 intersect – controls the flow of water from Lake Orion into the creek.

Lake Orion Police Chief Jerry Narsh, Village Council President Ken Van Portfliet and Village Manager Joe Young have been in contact with local, county and state officials to address problem.

On Saturday, work crews will install a temporary cofferdam into Lake Orion to prevent water from flowing over the dam, which will allow for a complete structural assessment and then repairs, said Olukayode Adefeso, MDOT Metro Region Bridge Engineer.

Southbound M-24 along the curbside will be blocked during the installation of the cofferdam, but traffic will remain open in both directions, Narsh said.

A cofferdam is an enclosure built within or across a body of water to allow the enclosed area to be pumped out, creating a dry work environment for the major work to proceed.

Adefeso said repairs could take about a month.

“It’s out of an overabundance of concern for the community that all of these steps are in place,” Narsh said. “That’s first and foremost: our citizens and their safety and the safety of their property is extremely important.”

Van Portfliet said village officials would have meetings throughout the day on Friday, including meetings with additional engineering consultants.

“We’re expecting to mobilize tomorrow. We’ll have a crane on M-24 placing a temporary dam in place on both sides. It’s really precautionary. We need to find out what’s going on, because right now we have water coming from places that the dam is not designed to have water coming from, such as underneath,” Van Portfliet said, adding there is no immediate danger to traffic over the bridge, or the public along Paint Creek.

The problem with the dam

“It appears to be some type of erosion under the bridge. There’s about a foot of water that travels under the bridge, and at the center bridge support, along the sides of that support, there’s some erosion that created a path for the water. Instead of going over the top of the bridge, it’s going down and underneath the spillway,” Narsh said.

“So, when that happens you can’t control it with the blocks like we normally do on the top of the dam,” he said.

The DNR discovered the problem during an inspection on Aug. 11, Narsh said, and the village immediately began contacting the MDOT and Oakland County and began monitoring to make sure the water levels had not changed

“Starting tomorrow morning (Aug. 19) a cofferdam, or temporary dam, is going to be placed on the lakeside. And once that’s in place, all risk of any problems with this dam is gone. All the water will cease from flowing over that dam,” Narsh said.”

Adefeso was on site Thursday and again on Friday morning to assess the dam, saying MDOT needs to conduct a detailed inspection to determine the extent of the problem.

“The major concern, the precautionary concern we have is for the dam itself. The dam as we see it during the routine inspection, there’s a depression that we noticed in the channel of the dam,” he said. “Normally, we have an emergency action plan, which we are of course exercising right now and taking all the precautionary measures that are necessary in terms of notifying all the agencies that need to be notified.”

Van Portfliet said the cofferdam will be in by the end of the weekend and will allow officials to formulate the plan.

“Once that cofferdam is in, then any risk is truly minimalized at that point because water won’t be coming over the structure,” Van Portfliet said. “Then we’ll get an opportunity to get in there and examine anything that may be happening, as far as cause. Action plan from that point on to be determined.”

While the dam is repaired, motorists do not need to worry about traveling on the bridge.

“Concerning the bridge itself, we have no concern about the structural integrity the bridge. The bridge by itself is performing as expected,” Adefeso said.

“What we are trying to do right now is a little bit of a drawdown of the lake. At the same time, doing the drawdown allows us the opportunity to be able to put in the temporary dam on the lake side to be able to do the appropriate detailed inspection of the dam itself, making sure the depression that we see – I think some people have called it a sinkhole – at the same time we will be able to quantify the damage that is there,” Adefeso said.

“Based on the findings, the appropriate repairs will start. We are projecting that this will probably take about a month to address the issues that we have seen,” he said.

Public Safety

If, in a worst-case-scenario, there was a need for evacuations, Narsh said, “The infrastructure’s in place. Everyone’s been briefed. Everyone knows what to do. But we really don’t anticipate it.”

Narsh has met with all the emergency management teams up to the state level and the village has an Emergency Action Plan in place.

“Both the Lake Orion Police and Orion Fire Department would literally go door-to-door if there were any issues of flooding. And if needed, we have an infrastructure in place for evacuation for anyone who’s home would be so damaged,” Narsh said.

“The good news is, MDOT has been really extremely efficient and fast on this. We really give them credit. Their hydraulics engineers, everyone, were here yesterday (Aug. 17).”

Adefeso says a detailed inspection now will most likely preempt any problems that would have occurred.

“For right now, there is nothing to really be worried about. We are just staying ahead of the curve. Should there be any emergency, we need to do the detailed inspection so that we can contain what is out there and be able to address it before it grows any bigger,” Adefeso said. “What we’ve seen so far, we don’t really think there is anything for anyone to be worried about.”

Cost of Repairs and Community Impact

MDOT and the village are co-owners of the dam and would share in repair costs, said Van Portfliet, adding that the dam was built in 1987 with the construction of M-24.

“I expect that we will have some expense tied to this. What that may be, I’m not sure. I can only guess and that wouldn’t be fair. But I’m going to work the best I can, the hardest I can, for our taxpayers. I’ve already researched FEMA (Federal Emergency Management Agency) opportunities. I’ve already talked to the county about possibly a low-interest loan.

“We’ve looked at what our resources may be; we’ve contacted MML (Michigan Municipal League) our insurance carrier; everything’s being done.”

“MDOT’s really been the champion for us. They’ve been here, on site, yesterday all day, today. I couldn’t thank them enough. I’ve never had such a great response from a state agency before,” said Van Portfliet.

“We’re making all the effort that we can to make sure that the lake level maintains the same level to continue the boating season.”

We’ve got the Dragon festival coming up, Labor Day weekend, all of that activity. Yet, we’ve taken all precautions. We’ve reviewed our Emergency Action Plan (EAP), we’ve been in touch with the county, the state, neighboring communities. We’ve had meetings with the fire and police departments. Everything’s in place if we were to have a larger risk evolve out of this we’re ready to act. We’ve done everything we can as far as providing safety and welfare of the community.”

Water Levels

The village still plans to begin the scheduled water level drawdown on Lake Orion on Sept. 12, allowing property owners the chance to make repairs. During the dam repair, officials said lake water levels may fluctuate slightly, but should not create a problem for lake users.

As for Paint Creek water levels, Narsh said officials will use the “gate-lowering system to bring water into the creek” to maintain that water level.

Water also will be diverted to the side flow – the DNR drawdown tubes – on the side of the dam. The drawdown tubes feed cold water from the bottom of the lake, preventing the creek from getting too hot so the fish can survive, Narsh said.

“It’s under constant monitoring. We know that some water is coming underneath the spillway. It’s not a lot of water. The important thing is, that amount of water has not changed in a week,” Narsh said, adding “slight amounts of water” would be diverted back to Paint Creek using the system the village uses to lower the lake level.

Questions and concerns should be directed to Village Manager Joe Young at 248-693-8391, email at youngj@lakeorion.org, or LOPD Chief Jerry Narsh at 248-693-8323, Police@lakeorionpolice.org