TTC Subway Damage
It would not be a pleasant experience today, to be the contractor that undertook the excavation work that caused the damage to the subway tunnel yesterday. Although it is in the early stages of the investigation, it is obvious that someone was digging in a place where the subsurface utilities (tunnel) were not adequately identified. It will be interesting to see if the contractor had “complete locates”. Regardless, no matter what locates they had (if any) were certainly not adequate. It will also be interesting to find out if the excavation contractor is liable or the engineer/project manager or both.
Some excerpts of a Globe and Mail story are below:
A construction accident by a third-party contractor working for Enbridge forced the TTC to close part of the Yonge subway line during the evening rush hour Wednesday, stranding some 300,000 commuters. The route was shut down between Bloor and Eglinton stations for about six hours before opening last night around 8:30 p.m.
The service interruption was the result of damage caused by a construction crew that was cutting a trench on Jackes Avenue, which runs over the underground subway tracks south of St. Clair Avenue. The contractor, identified as Link-Line, was relocating an Enbridge natural gas pipeline. In the process, they cut through the street and into the subway tunnel.
“Initial reports indicate that it is something that could have been prevented with a little more know-how or preparation,” said TTC spokesman Kevin Carrington. “We really don’t know at this point why it happened, but we know that this crew was working on it, so right now the blame seems to be falling on their shoulders. Definitely it was not the TTC’s fault.”
TTC officials are considering whether to recover costs associated with the disruption, such as staff overtime, from whoever was responsible for breaching the tunnel.
“Money’s a big issue right now, and time and safety is a big issue. So eventually I think it’ll have some sort of quantitative value, so to speak,” Mr. Carrington said.
Debbie Boukydis, an Enbridge spokeswoman, said the company is co-operating with the TTC, the City of Toronto and the provincial Labour Ministry as they investigate the mishap.
“In terms of finger pointing at this time, that’s why these investigations are so important to make sure that we are able to determine exactly what happened. Number one, to learn from any mistakes, if that was the case, but also to assess what happened and who actually was at fault,” she said.
Ms. Boukydis said Link-Line was working for Enbridge and was performing an emergency relocation of a natural gas pipeline at the city’s request. Such work is closely co-ordinated with city officials, she said, including obtaining permits and determining the location of road cuts. The work started last Friday and was to have wrapped up by weeks’ end, but is now on hiatus.
The accident damaged a 22-metre long, 42-cm deep concrete slab. A small amount of debris fell onto the tracks. The TTC shut the line because it wasn’t safe to run subway trains because of the vibrations the fast-moving trains might create, fearing a worst-case scenario of a cave-in or tunnel collapse.