Lake St. George dam update

No immediate action taken after meeting with state officials

$92,000 repair estimate to be voted on at special town meeting
By Fran Gonzalez | Oct 02, 2019
Photo by: Fran Gonzalez Liberty Road Commissioner Tammy Reynolds, left, plays underwater video of the Lake St. George dam culvert, showing interior gaps in joints between cement sections, for Kathy Howatt of MDEP and Andrew Manzi of MEMA Sept. 24.

Liberty — Throwing a Hail Mary of sorts at a meeting with state officials, Road Commissioner Tammy Reynolds presented a diver's video of the Lake St. George dam that showed gaps in several sections of a cement box culvert designed by Maine Department of Transportation. She did not get the reaction she'd hoped for.

Members of MDOT, the Maine Department of Environmental Protection, Maine Emergency Management Agency, town officials and Citizens' Association of Liberty Lakes met Sept. 24 about concerns over the leaking dam. Discussion was curt at times but no state agency conceded.

Meanwhile, a special town meeting is scheduled for Wednesday, Oct. 9, to consider spending $92,000 to repair the dam's sluice gate and the wall to which it is attached.

The 1820s era dam has had leak issues over the years, including a deteriorating steel culvert under the road. In 2015, MDOT overhauled the road across the town-owned Lake St. George dam and installed a cement box culvert, similar in style to large-scale LEGOs with rubber gaskets surrounding each joint.

Since then, Reynolds said, water has found its way around the outside of the new culvert — she said she believes it is the result of poor construction planning by the state. It was not until the town hired Calligan Diving Service of Searsmont that officials had images to back up their claim.

"The culverts have separated," Reynolds said, pointing to the video on her laptop. "The rubber (gaskets are) gone, there is about an inch-and-a-half gap. They are pinched together on the top in about eight sections of the state's culvert. That is what we found."

Reynolds said the video also showed a hole underneath the spillway, where the gate comes down, "large enough that you could throw a dog through," making it almost impossible to adjust the water level.

Brad Foley of MDOT said, "I'm not convinced there is an issue here, just because there is a gap," and said there typically is a membrane over the top of all of the joints that would prevent a breach.

Doug Coombs of MDOT echoed his thought and said, "some don't butt up tight." He added they investigated earlier in the summer and looked at the condition of the road and access road, and found nothing "unusual with the road itself."

At an earlier meeting, MDOT officials had said they would consider taking core samples of the new concrete culvert, boring down into the cement to see if there were any openings where aggregate might settle, though the test was never performed.

"We found there was really no distress," Foley said. "There's nothing saying there is a problem, based on the condition of the roadway, the condition of the access road and the condition of the rip rap."

Kathy Howatt of MDEP said they had been out earlier this summer and noticed debris in front of the dam and also that the water level was being managed by the box culvert.

"It appeared to us water level management was in compliance based on measurements we took from the top of the spillway, the distance to the water from the spillway," she said.

Linda Breslin of the Citizens' Association of Liberty Lakes said the only reason they met the 1985 water level order in the early part of the spring this year was that they had not removed debris from the clean-out grate, which slowed the movement of outgoing water.

In an added wrinkle to the dispute, MDOT contends it owns the new box culvert and access road, and no work can be done to those structures without the department's consent.

David Gardner of MDOT said, "My point is you ain't working on the culvert; if you thought there was something wrong with the culvert, you are not to go in and work on it. This diver should have had DOT permission before diving in there."

This led to an exchange between Reynolds and MDOT.

"...Don't touch the culvert? So does that mean you guys are going to clean that?" Reynolds asked, referring to a clean-out grate in front of the culvert.

"Ahh, no," Coombs said. "That is your responsibility, to clean without touching the culvert."

Ultimately, MDOT requested the diver's video and report so they can investigate and analyze further to determine whether there is an issue.

According to a report by Richard Calligan of Calligan Dive Service, water is entering the new culvert through the seams under the road.

"We saw this and recorded it in several locations," Calligan wrote in an email. "It appears the culverts are settling, causing this problem. In order for the water to be coming into the culvert, it would suggest that the water is flowing on the outside of the culvert."

The repair estimate from Calligan said the majority of the leak, in their opinion, was coming from the sluice gate and wall to which it is mounted, and proposed replacing the gate. Calligan also proposed repairing the cracks and holes in the wall with a non-shrink grout and blanketing the existing wall with 4 inches of new concrete with rebar reinforcement.

"If allowed by the state, we would also pour Bentonite clay chips into the upstream embankment to slow down or seal any seepage or leaks running along the new culvert," Calligan's estimate says.

The work is estimated to cost $92,000 and would take approximately 10 weeks to complete.

 

Diver's video of culvert at the Lake St. George dam Sept. 2019.
The town of Liberty hired Calligan Diving Service of Searsmont to shoot a video showing gaps between the MDOTs cement culvert blocks at the Lake St. George dam Sept. 2019, to illustrate how the dam is leaking. (Courtesy of: Calligan Diving Service of Searsmont)
Comments (0)
If you wish to comment, please login.