Concrete coming: Head Tide Dam update

Mon, 08/26/2019 - 8:30am

With some ledge and the abutment gone from Alna’s Head Tide Dam, project manager Maranda Nemeth said Friday, she can already picture how the water and fish will likely travel the channel the work has opened up.

“It’s very rewarding to see that,” Nemeth said in an interview on the Head Tide Road bridge. “(The fish) are going to have a lot of space and ability to move through this reach of the (Sheepscot River). I’m really looking forward to it.”

In the meantime, tons of sand bags remained in the river so work could continue. Where the abutment had stood, workers on scaffolding were getting ready for the concrete to be poured for the new overlook. “We are definitely still on schedule (and) progressing through these critical steps,” Nemeth, of Midcoast Conservancy, said. 

Nemeth said rebar was being set up to permanently reinforce the concrete projected to be poured into temporary forms Wednesday, Aug. 28. The concrete will cure and set, then the forms will come off; and in September, workers will exit the river, she said. Trailwork, a retaining wall, grading the parking lot and landscaping will follow.

“It’s coming together.” Ledge continued to be removed from the riverbed below the overlook area, she said.

As far as Nemeth is aware, the concrete dam does not have rebar. “In the gatehouse, we saw some old steel railroad ties that were intermittently put in there, so they likely were trying to achieve steel reinforcement, but it wasn’t very consistent. We don’t know the rest of the dam, but from what we can see, we don’t see any rebar.”

Has the project revealed anything else about the town-owned, century-old dam? The newly exposed part turned out to be solid concrete with aggregate mixed in, Nemeth said. So the dam’s right side, at least, is neither hollow nor wooden inside, which it could have been, she said. “We don’t know what’s in the (dam’s) center, though.”

Weather has not posed a problem, including the inch of rain earlier in the week, she noted. “The site withstood it, so we were really grateful for that.”