Sinkhole stabilized in Rossford

ROSSFORD – Phase one of slope stabilization for a sinkhole that opened up at the end of Eagle Point Road has been completed, and phase two is now in the design phase.

“The central issue is drainage. There’s a difference between road reconstruction and drainage,” Todd Audet, Rossford director of economic development, said. “I want to fix this for the next 50 years.”

The sinkhole was impacting the stabilization of the hill.

“It was literally, probably twice the size of this Suburban,” Audet said, comparing it to the city vehicle. “The slope stabilization was an emergency situation. We’ve stopped the immediate problem.”

The side of one of the concrete drainage structures had blown out.

“We would have lost this whole hillside if we didn’t know about it,” Audet said, adding that he is thankful to the resident who alerted the city.

It was determined that the sinkhole at the end of Eagle Point Road may have been caused by improperly bedded pipe and the failure of the sub-grade. Emergency stone was ordered to fill the hole prior to the July council meeting, using $50,000 in city emergency funding. It is now in the first phase of slope stabilization.

Eagle Point Road stops in a dead end, at the top of a drop off to the Maumee River. Audet said that people visiting the Anshai Sfard Cemetary used a bench, located next to the guard rail, as a viewing site overlooking the Maumee River.

Audet, a civil engineer with war-time engineering experience from the Air Force, is in charge of the project.

“This was relatively easy. There were no bullets to deal with,” Audet said.

Previous job comparisons aside, he pointed out how the stormwater overflow situation came to a head.

“This whole area looked like a jungle. All I could see was this concrete pipe sticking up next to a 10-foot sinkhole,” Audet said. “I declared an emergency, because I have that authority, and got contractors out here.”

Much of the stormwater system for the city funnels down to the concrete drainage pipe structures leading to the river, approximately 50 feet below the road surface.

“The 36-inch pipe had sucked in much of the bedding for the pipe and sent it down to the river,” Audet said.

“What it does is this one will fill up and dump to the next one, and the next one. It slows the water flow down. Because if you had 36 inches of pipe, and all the water was going down with this much head pressure, it would put the water in the air at least two-thirds the height of this hill,” Audet said of the water that would be fountaining into the Maumee River.

More than 50 years ago, the city accomplished the drop in pressure, for that kind of water volume, by installing five sequential vertical 6-foot diameter culverts, with about a 40-foot depth. It was the last one in line, just before the exit pipe, that developed a hole in its side. Instead of completing the proper drainage route, water was shooting back into the base of the hill, causing the sinkhole.

Audet had a crew go in, cut down the vegetation blocking access to the infrastructure, filled the sinkhole and then they added several tons of rock to stabilize the hill.

“There was a guardrail, and some kind of a bench. That whole area was all wooded, because it was not maintained,” Audet said, who got the call from a local resident about the sinkhole.

The guardrail at the end of the road had been removed for access vehicles. It was replaced with a Redi-Rock barrier. Audet said that it was insufficient to stop a vehicle driving at higher speeds.

While grass has been planted, with netting, to prevent erosion, there is more work to be done. Phase 2 of the project will be creation of a series of retaining walls that will also add strength to the culverts. Bid specifications for the engineering of that final infrastructure are now being written.