LOCKPORT – Repairing a caved-in sewer main and resulting sinkhole at one of Niagara County’s busiest intersections may cost $30,000, Town Supervisor Marc R. Smith said Wednesday.
The work at South Transit and Robinson roads, the intersection of Routes 78 and 93, has blocked a right-turn lane for northbound traffic.
Repairs are proceeding slowly because of the large varieties of underground infrastructure the sinkhole exposed, Smith said.
A town water main affected by the shifting ground broke Tuesday, Smith said.
Other pipes exposed included two 6-inch natural gas lines, a 30-inch Niagara County Water District main and electrical lines detecting traffic to change the traffic signals.
For the first few days, sewage flowing into the trench stymied work, according to a report from Town Engineer Robert D. Klavoon.
The problem started on the afternoon of July 25, when sewage backed up into the nearby town water and sewer building on Robinson Road. It became apparent that a sanitary sewer line in the vicinity was clogged.
Town workers tried to use water jets to clear 18- and 24-inch sewer mains, while on July 26, a Newfane sewer vacuum truck worked four hours trying to suck debris out of a manhole. Another company, Pipe Eye Sewer, hauled away three truckloads of debris from a manhole.
However, by July 29, the level of sewage in the manholes remained high. At about 1 p.m. that day, the sinkhole opened in the grass at the southeast corner of the intersection, exposing one of the gas mains and undermining the sidewalk.
By 8 a.m. July 30, the sidewalk had collapsed, and it was apparent the sewer main also had caved in.
Smith said the pipe was made of concrete; Town Clerk Nancy A. Brooks said it was about 40 years old.
Councilman Paul W. Siejak said at its worst, the hole was as much as 17 feet deep and 12 feet wide.
Mark Cerrone, a Niagara Falls construction company, started excavating on the afternoon of July 30 and worked through Friday.
The cause of the break is unknown. Brooks speculated that the concrete pipe may have been done in by years of vibration from the heavy traffic at the corner.
It was unclear how long the repairs will take, although a sign was posted Wednesday at the intersection, advising drivers that road work will begin Monday.
The broken main serves not only Robinson Road and South Transit as far north as the City of Lockport border, but also all the residential streets east of South Transit, according to Klavoon’s report.