August 18th 2005
Ontario Power Generation awarded a $600 million dollar contract to Strabag AG Company to design and build the new Niagara Tunnel.
September 14th 2005
The ground breaking ceremony was held. The Ontario Power Generation announced the start of construction of its $985 million dollar, 10.4 kilometres (6.46 mile) Niagara Tunnel in order to increase the output of power from Niagara Falls. The Niagara Tunnel project is estimated to cost $600 million dollars and an additional $385 million dollars for remedial and other work costs.
May 18th 2006
The Province of Ontario Minister of Energy, Donna Cansfield, visited Niagara for a tour of the construction site announced the nickname of the Tunnel Boring Machine as "BIG BECKY". A grade 6 class from Port Weller Elementary School provided the winning entry for the contest to name the TBM. Under the direction of computer and science teacher, Kevin Dyck, the class selected the name after much "brainstorming". They called it BECKY because it is a feminine version that pays tribute to Sir Adam Beck.
August 8th 2006
A ceremony attended by Ontario Premier, Dalton McGuinty, and other officials was held at the starting location of the Niagara Tunnel Project near the Sir Adam Beck Power Generating Stations. Premier McGuinty flicked a switch to turn on the cutter head of the Big Becky. Importing a European tradition, Doctor Robin Williams, the Regional Municipality of Niagara Medical Officer of Health, was named the patroness of the Niagara Tunnel Project by officials of Strabag AG. Naming a patroness is based upon a religious tradition of St. Barbara, the patron saint of miners, construction workers and engineers. Doctor Williams’s role is to keep up to date on the tunnelling project and to be a public ambassador for it. According to traditions associated with tunnelling, naming a patroness of the tunnel will keep the workers safe.
August 2006
The Regional Municipality of Niagara and Ontario Power Generation drafted an agreement that approximately 3.5 million tonnes of Queenston Shale had to be excavated and then provided to the brick manufacturing industry for free. Queenston Shale is the sole raw material used for the production of clay bricks in Ontario.
August 2007
Big Becky neared the 1,000 metre (3,281 feet) mark. Progress had been extremely slow because of frequent vertical rock falls as a result of unforeseen geological rock structures. It was hoped that the unstable rock sections were behind them as the TBM bored deeper underground. Several rock falls weighing an estimated 10-20 tons stopped the boring progress for lengthy periods. In order to reduce the frequency of rock falls, horizontal support rods are being installed in the rock above the TBM in advance of the cutter head.
In order to reduce airborne dust pollution at the debris dump site, a containment building has been erected.
September 22nd 2007
Big Becky reached the milestone of the first 1000 metres (3,281 feet).
January 21st 2008
Big Becky, the nickname for the $35-million tunnel-boring machine, reached approximately 1,650 metres (5,413 feet) and at this point was located at its maximum depth. The current location is under the ancient buried St. David’s Gorge. Because of very difficult, unpredictable and unstable rock conditions, Becky has been progressing at forward rate of several metres per day. This unfortunate delay in progress created the first setback as the targeted completion date of the entire project changed from 2009 to 2010.
Six shafts from the surface to the tunnel were drilled near the Whirlpool Road site. Each of these shafts allows the tunnel to be dewatered using massive mobile water pumps, if required.
March 5th 2008
Strabag has announced further delays in the Niagara Tunnel Project. Big Becky was making very slow progress under the very unstable rock conditions. It was thought that they might have to chart a new course and revise the schedule to make up for lost time. Officials for each company report that progress on the Niagara Tunnel Project continues to be slower than expected.
"You’re dealing with nature. You can’t predict the rock condition for 10 kilometres," said Ernst Gschnitzer, Strabag’s project manager, who oversees the construction of a third hydro tunnel under the city of Niagara Falls.
What excavators call "over-break" continued to be the problem, the same situation that slowed progress from the previous year. Once Big Becky cuts a portion of the tunnel, loose rock from the ceiling falls in behind the machine. The cavities will be filled in to make a smooth surface before the tunnel is finished, he said. But for now, removing the rock and digging through "unstable" material is hindering progress.
To compensate for the delays, Strabag wants to alter the alignment of the tunnel, both vertically and horizontally. On the south side of the St. David’s Gorge, the tunnel will go higher than first planned. That will allow the excavation to get out of the difficult conditions and into more predictable rock, said Gschnitzer.
According to the Niagara Peninsula Conservation Authority, the buried St. David’s Gorge is an abandoned channel that has been filled in with glacial debris including gravels, sands, tills, silts and clays. The ancient gorge is thought to have been 116 metres (380 feet) wide and up to 79.25 metres (260 feet) deep. It has been estimated at approximately 22,000 years old.
A portion of the tunnel will also be shifted toward the Niagara River from its original alignment, which ran approximately underneath Stanley Avenue. Strabag has applied for necessary approvals to make that change. The company expects to hear a decision in a few months, Gschnitzer said.
"We hope it won’t change that much. It will go into 2011," said Gschnitzer. Last fall, Ontario Power Generation’s board approved August 2010 as the completion date for the tunnel. When work began in September 2006, Strabag expected it could complete the work by fall 2009. OPG says Ontario taxpayers are protected from cost overruns because it gave Strabag a design-build contract meaning the company agreed to build the tunnel for a fixed price, said OPG spokesman John Earl. The tunnel work is pegged at $600 million.
At the beginning of March 2008, the TBM had excavated 1,800 metres of the 10.4-kilometre tunnel.
By December 31st 2007, the TBM had excavated 1,609 metres of the tunnel.
By September 2007, the TBM had excavated 1,350 metres of the tunnel, less than half the distance Strabag had hoped for at that point. Once the TBM excavation reaches 2,300 metres (2.3 kilometres), Strabag will be in a position to reassess how to make up for lost time in the remaining 8.1 kilometres of the tunnel.
May 24th 2008
Big Becky passed the 2 kilometre point in the Niagara Tunnel Project, but it is so far behind that Ontario Power Generation (OPG) and Strabag AG had to review the cost of the $630-million project and its schedule.
"The Niagara tunnel is progressing slower than planned. The drilling conditions have been challenging," president and chief executive officer Jim Hankinson said Friday. OPG officially announced that it remains confident with the August 2010 completion target, which had already been revised once from 2009. This is contrary to Ernst Gschnitzer’s, project manager for Strabag, comment that predicted it won’t be completed until much later.
"It’s going to be 2012. We don’t see any possibility to be quicker, at present," Gschnitzer said.
After 2 kilometres, the TBM is one-fifth of the way into the 10.4-kilometre tunnel that will connect the Sir Adam Beck generating stations to the upper Niagara River, south of Dufferin Islands.
At the end of March, OPG’s first fiscal quarter, the tunnel boring machine had advanced about 1,848 metres. That’s only 239 metres further than where it was at the end of 2007, based on OPG figures. This is due to the fact that Big Becky was digging an average of 2.6 metres a day over the first three months of 2008. Compared to the expected average rate of 15 metres a day, this is considerably slower.
As part of the official review, three independent experts were brought to Niagara to examine how the project has gone since work began. They looked for mistakes that might have been made as well as ways to improve progress, an OPG official said. These experts were going to consult with both OPG and Strabag in June. OPG expects to have a better understanding of how the cost and schedule will be affected by July.
"We will provide further details about changes in the schedule and the cost when they are available," Hankinson said in a conference call to discuss the Crown Corporation’s first quarter results for 2008.
Since it commenced, the tunnel construction has been slowed by the loose rock conditions under the St. David’s Gorge. As Big Becky advances, loose rock from the tunnel ceiling falls in behind it, and the "over-break" rock has to be removed.
"Once we get beyond the St. David’s Gorge, we do expect better performance," Hankinson said.
“The tunnel-boring machine was 2,077 metres into the tunnel,” Gschnitzer said. His company expected to be "much further" along than it is now, after 20 months. "I can’t even tell you – several more kilometres," he said. “Removing the ‘huge amount of over-break material’ is the ongoing challenge”, he added.
“It’s impossible to know for certain what rock conditions exist before construction starts,’ Gschnitzer said. OPG could have spent more than $100 million on a more extensive rock study, he added, but "you would never be able to anticipate these rock conditions 100 per cent." Strabag has bought more equipment to remove that rock material faster. That reduces the time the tunnel-boring machine loses,” Gschnitzer said.
"We have worked on a consistent basis to make improvements. The rock conditions aren’t changed," he said.
"In the last couple weeks, our progress has been much better – more like six or seven metres a day," Hankinson said. OPG reported the "considerable uncertainty" about the schedule and cost until Big Becky reached the 2,300-metre mark, the point when the loose rock is expected to turn to harder rock, reducing the over-break concerns. Ontario Power Generation planned to review the entire $985-million estimate of the Niagara Tunnel Project. That estimate includes some work OPG is doing not directly related to the tunnel, including the refurbishing of the Toronto Power station on the Niagara Parkway.
On May 29th 2008, the TBM had progressed to 2,114 metre. Now slightly south of the St. David’s buried gorge, the TBM was averaging up to 7 metres per day but still experiencing heavy over-break (rock fall from the roof of tunnel).