By Dawn De Busk
Staff Writer

NAPLES — A few plow-truck drivers got a sudden jolt when their rigs hit the dip that recently developed on the Causeway.

Those unexpected jolts have resulted in phone calls from residents to Naples Board of Selectmen and Maine Department of Transportation officials to report what some have referred to as “a sink hole.”

The sizable dip in the pavement is located immediately after the Naples Bridge on the westbound lane of Route 302. A new warning sign lets drivers know about the upcoming change in the pavement beneath their wheels.

“People thought the road was sinking,” said MDOT Resident Engineer Craig Hurd, who fielded some of the phone calls from concerned residents.

“It’s not a sink hole. It’s just some settlement, and it was caused during the installation of the cofferdam,” he said.

The cofferdam is typically installed when building structures under water, he said. In order to put in the cofferdam, crews used a vibratory hammer. The vibrations caused settlements of sandy soil to move from under the pavement causing the roadway to sway downward, according to Hurd. However, the pavement did not crack, he said.

At this point, the best remedy has been putting up a bump sign and advising drivers to cross the bridge at 25 mph, which is the posted speed limit, according to Hurd.

“If people go 25, there’s no issue. But, people are going a lot faster with plows on the front of their trucks. If people are going through there at 40 mph with a plow, their plow is probably going to hit the pavement,” Hurd said.

“We put up a bump sign. We are going to put up a permanent bump sign there,” he said.

He added the dip won’t be a permanent part of the road, but frigid wintertime conditions prevent immediate repair of the offending spot in the pavement.

“If it gets worse, we’d have to rip off the pavement and put in some gravel. This time of year, if you start doing things like that you are making more of a problem,” Hurd said.

The issue of the dip on the Causeway came up during Monday’s selectmen meeting.

“We’re used to doing 35 or 40 mph over the bridge in the wintertime. It does shake you up a little bit if you’re driving a truck with a plow on it,” Selectman Rick Paraschak said.

“I’ve been getting phone calls on it. The resident engineer is well aware of the settling that is going on,” Paraschak said.

Town Manager Derik Goodine said his theories weren’t based in science, but from seeing the sandy soil that has seeped from between rocks when the 50-year-old riprap was removed.

“This has never happened there before. But, you’ve got vibrating from when crews put in the cofferdam. You’ve got voids under the Causeway. The vibration is moving the really sandy soil, and causing it to settle into the voids. That’s what I think created the dip,” he said.

“The sink hole on the Causeway needs to be fixed,” Goodine said during Monday’s meeting.