A sinkhole has damaged two

homes and authorities declared one to be unsafe, town officials said this afternoon.

The Hackettstown building inspector determined the home at 185 College View Drive had sustained damage to its foundation after a 40-foot-wide sinkhole opened up in the wake of a water main break Thursday night, officials said.

The occupants have been told the home is unsafe, although it was not mandatory they evacuate, town police Sgt. Darren Tynan said. A neighboring house at 183 College View Drive also sustained minor damage around the foundation.

A Maser Consulting Geotechnical engineer is scheduled to visit the scene Saturday to survey the damage.

The sinkhole, which is about 4 to 6 feet deep, appears to have formed underneath the sidewalk, Tynan said. It washed out a section under the road and driveway of 185 College View Drive while swallowing a portion of the front lawn of the neighboring home.

"It's a big area that was compromised by the sinkhole," Tynan said.

The cause of the sinkhole is undetermined, he said.

Police announced Thursday evening a water main had broken and closed College View Drive between Deerfield Drive and Carter Terrace. Tynan said that while the break was a factor in the sinkhole, the extent of its impact is unclear.

"We're not sure if the sinkhole that formed was caused from the main break or if there was already something wrong with the ground and the main break just made the problem worse," he said.

Officials inspecting the damage this morning said the ground was moving and they feared the sinkhole could grow.

"The concern is warmer temperatures come and loosen the ground more and cause more of the sinkhole to grow bigger," Tynan said.

The town engineer remained on site this evening. Crews from Elizabethtown Gas worked to cut a gas line under the road that could be compromised if the road were to collapse, Tynan said.

In the meantime, College View Drive remains closed between Deerfield Road and Carter Terrace. No timeframe has been set on when crews will begin repairs that will likely include a reconstruction of the road, sidewalk and curb.

"They want to see how far it's spread or if other holes are going to pop up," Tynan said.