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[TOareaFan]

Maybe every thread should have a disclaimer in the title that would save ksun some time.

"Note: if this project was being undertaken in any country other than Canada it would be a bigger, better project and would be completed faster."

 

[Woodbridge_Heights]

Blah blah blah. ZOMG! The island airport tunnel is only 200M and took more than 8 months. CLOSE DOWN THIS TROJAN HORSE OF AN ISLAND AIRPORT!!!

 

[PinkLucy]

Ksun likely thinks it's a no account rural airport anyway

 

[kotsy]

http://www.blogto.com/city/2014/11/what_the_island_airport_tunnel_looks_like_right_now/

 

[muller877]

wow, 3 years for this 100 meter tunnel.
They might try to win the slowest built tunnel Guinness record.
The Millau Viaduct, an engineering wonder in the world spanning 2.5km with all the technical challenges, with 4 lane traffic 250 meters in the sky, took about the same time.

The 50km Channel Tunnel took 6 years.
I am so impressed.

I am actually impressed with the price. <$100M for a 240M tunnel. This includes the costs of the buildings/elevators, etc at both ends. Could we hire them to create a LRT tunnel under the CBD? I'm sure the TTC would want $1b for the same build.

 

[mrxbombastic]

Their price come in at $343.75/km ($82.5M/0.24km). This is in line with the oft cited and widely regarded $300-350million/km price tag associated with subway/tunnel building in the GTA

so not much benefit to be found in this particular group of builders.

 

[Tuscani01]

Their price come in at $343.75/km ($82.5M/0.24km). This is in line with the oft cited and widely regarded $300-350million/km price tag associated with subway/tunnel building in the GTA

so not much benefit to be found in this particular group of builders.

Mind you, this is a tunnel under a lake. I'm sure it would have cost much less had there not been a lake above it...

 

[innsertnamehere]

This is hardly a "regular" tunnel project.

Just straight tunnelling without stations also costs significantly less, often closer to the 100 million per km range (look at rail tunnels for regional rail without an underground station)

 

[muller877]

This is hardly a "regular" tunnel project.

Just straight tunnelling without stations also costs significantly less, often closer to the 100 million per km range (look at rail tunnels for regional rail without an underground station)

There are 2 "stations" in this tunnel. The <$100M budget included tunnelling under the lake, a new water main for the city AND 2 "stations" with high speed elevators at each end.

And the first 1 meter of a tunnel is always the most expensive (once you get going an extra km is not that much money)

 

[rbt]

Mind you, this is a tunnel under a lake. I'm sure it would have cost much less had there not been a lake above it...

Not really. A surprisingly large part of the TTC subway system is below water.

 

[interchange42]

There are 2 "stations" in this tunnel.

These "stations" are an order of magnitude less elaborate than what subways or LRTs require.

42

 

[nfitz]

Their price come in at $343.75/km ($82.5M/0.24km). This is in line with the oft cited and widely regarded $300-350million/km price tag associated with subway/tunnel building in the GTA

so not much benefit to be found in this particular group of builders.

Little benefit. The Eglinton tunnels currently under construction are about $40 million/km. The Spadina tunnels are similar.

It's not the tunnels that cost so much. It's the stations. The $300-$400 million/km for subway also includes track, signals, power supplies, and trains.

 

[Mulder]

Channel tunnel had plenty of its problems too, including fires, diplomatic issues due to illegal entry to the UK, and death of 8 construction workers.
You talk as if the small airport tunnel has its unique technical challenges that somehow justify its tardiness. They used 11 boring machine because it is a much bigger tunnel allowing cars and express trains to go through, not a small pedestrian tunnel.

It's easy for people who are not in the engineering/construction world to criticize timing, cost, etc.
Comparing projects is build x years ago in x country is useless. As they have different safety laws, weather, etc.

Building in the middle of nowhere where you know there will be no conflicts is MUCH easier and cheaper than in a urban environment where you have to relocate utilities. Even worse is when you find conflicts that were not on any plans. (as such in this project).

 

[BurlOak]

Little benefit. The Eglinton tunnels currently under construction are about $40 million/km. The Spadina tunnels are similar.

It's not the tunnels that cost so much. It's the stations. The $300-$400 million/km for subway also includes track, signals, power supplies, and trains.

I have not seen a cost breakdown of why underground is so expensive. track, power, trains are needed for all modes - even on street LRT.
But what proportion of the cost is signals, stations, and ventilation?

 

[innsertnamehere]

signals and trackage cost something like $20 million per km, stations are typically in the $100-$150 million area. Large stations such as ones with underground bus terminals can run upwards of $200 million. Most of Eglintons stations are probably closer to $100 million.

Then there are trains, tail tracks, crossovers, etc. that all add costs as well.