Even More On Snubs and Megaproject Over-runs
Niagara gets a tunnel. Windsor again gets the shaft again.
I found the story on the rail tunnel interesting...so far about a 25% cost overrun. I wonder what that means for our Arena megaproject.
A gigantic bore
ZOE CORMIER, Saturday's Globe and Mail
The city that boasts North America's most powerful waterfall will soon be sitting on top of a massive hole created by the world's most powerful hard-rock boring machine.
Using a drill with a diameter of 14.4 metres, Austrian construction contractor Strabag will begin digging a tunnel this summer to divert water from the Niagara River to the Sir Adam Beck Complex. The tunnel will run 10.4 kilometres, about 100 metres beneath the city of Niagara Falls...
The TBM will drill through the rock seven days a week (excluding routine maintenance checks) for up to three years. Its final destination is the banks of the Niagara River, where a temporary dam will prevent the tunnel from being flooded prematurely.
The diameter of the tunnel, once beams and concrete are put in place to support the walls, will be about 12.7 metres.
The largest tunnels in the world made with boring machines are only slightly bigger -- a pair of 15.2-metre drills were used to complete two tunnels for roads in Madrid last year -- but the city of Niagara Falls sits on top of tough Queenston shale, while the Spanish tunnels were gouged through gravel and sand. The harder the rock, the more difficult it is to drill a wide tunnel...
The tunnel, which will deliver about 500 cubic metres of water per second, is expected to boost the amount of "clean, renewable, low-cost energy you can get from the Beck station by 14 per cent, about 1.6 terawatt-hours" a year, OPG spokesman John Earl says. That's enough energy for about 160,000 homes.
"To put it in context," Mr. Earl says, "the province of Ontario last year used about 150 terawatt-hours. So 1.6 terawatt-hours is a small percentage over all, but for just one plant, it is a considerable addition."
The construction of the tunnel is expected to cost close to $1-billion. The TBM alone will be about $30-million...
The drill will be able to go as fast as five metres an hour, but engineers expect it to move no more than 15 metres a day on average; although it will be operational 24 hours a day, only about 12 hours will be spent actively drilling. It will have to stop while construction workers stabilize the sides of the tunnel to prevent a cave-in."
Additional Investments for the Gotthard Base Tunnel
AlpTransit Gotthard is the construction project of the century. The total time for planning and building the 57-kilometres-long Gotthard Base Tunnel will be about 25 years. The construction project is also extremely demanding, both technically and financially. The long implementation time means that new developments in standards and technology must be included in the construction process.
During construction of the Gotthard Base Tunnel (excluding the Ceneri Base Tunnel) additional investment costs arise mainly in relation to safety and the technical state of the art as well due to politically caused delays and phasing under the law for financing public transportation. Relative to the cost estimate of CHF 6,323 million based on the scope of construction of the Gotthard Basis Tunnel originally assumed by the Swiss Federal Government, according to present knowledge additional costs of CHF 1,712 million will arise. The estimated project costs are expected to amount to CHF 8,035 million.
These additional costs of CHF 1,712 million consist of additional investments for various project improvements. They include improvements for people and the environment (CHF 101 million or 1.3 % of the estimated project costs), for example for construction of an underground branch-off between Erstfeld and Amsteg to allow for a later routing variant «underground long». However, they also include costs due to politically determined delays (CHF 506 million or 6.3 %) and for phasing. Additional costs for safety and state-of-the-art technology amount to CHF 683 million or 8.5 %. They result mainly from investments to keep pace with technological developments in railway systems. Geology causes additional costs of CHF 363 million or 4.5 %. These relate, for example, to unforeseeable fault zones which were encountered in the Bodio and Faido sections. Additional costs for contract award and construction amount to CHF 59 million or 0.7 %.