Canada Line | Completed

[agrant]

They've probably got a sump or catch basin for occasions like this. If it works properly, the water should only get so high before the pump is activated.

[jlousa]

I believe someone mentioned this earlier, there isn't a pump there as it wouldn't fit so they bring it in every night to empty the catch basin they didn't expect there to be a need to pump out the water more then once a day over night at it's worst. Hopefully someone has the actual details. As for where the water comes from, by the time the trains get to the they would be carrying pretty minimal water from outside, most of it probably comes from some seeping.

[lightrail]

Originally Posted by jlousa

I believe someone mentioned this earlier, there isn't a pump there as it wouldn't fit so they bring it in every night to empty the catch basin they didn't expect there to be a need to pump out the water more then once a day over night at it's worst. Hopefully someone has the actual details. As for where the water comes from, by the time the trains get to the they would be carrying pretty minimal water from outside, most of it probably comes from some seeping.

That seems a stupid short-sighted decision. Everybody knows that underwater tunnels leak and you need to get the water out somehow. They need to dig a pit and install a pump, or a drainage tunnel from the low point to one side of False Creek then a pumping station.

[deasine]

Originally Posted by lightrail

That seems a stupid short-sighted decision. Everybody knows that underwater tunnels leak and you need to get the water out somehow. They need to dig a pit and install a pump, or a drainage tunnel from the low point to one side of False Creek then a pumping station.

I don't think they expected this would happen to this extent especially since Vancouver's false creek portion isn't very long.

[Zassk]

So... the tunnel wall just needs re-sealing?

[BCPhil]

No, I think it's just because during the last week we have seen more rain in a day than we usually seen in the wettest week or even month. It's probably just all the rain getting into the tunnels at the stations near false creek, and the water rolls downhill to the low point. It probably gets in near the vents at the stations.

The day I noticed all the water in the tunnel it was raining rather hard all day long. A Pineapple Express isn't just a funny movie. If the tunnel there was leaking, this would be a regular occurrence, and not just happen on days it rains.

[Zassk]

^ Oh, I'm surprised there aren't drains/pumps or something at each end of the bored tunnels to prevent runoff heading in. I guess Dunsmuir tunnel doesn't get exposed to this problem, and the cut & cover sections don't have any low points.

[crazyjoeda]

LA's system must bleed money. They have more lines than Vancouver and according to the ridership statistics that I saw they only get about 300,000 riders a day, low for a city that large.

[Yume-sama]

Originally Posted by crazyjoeda

LA's system must bleed money. They have more lines than Vancouver and according to the ridership statistics that I saw they only get about 300,000 riders a day, low for a city that large.

Well, there's a reason California is completely bankrupt and pays government employees with IOU's

[Axe]

Originally Posted by mr.x

How is water even getting into the tunnel?

The tunnel is below sea level. It goes under flase creek There will always be water in the tunnel. No way to stop water. water seeps though Concrete as it is porous.

[Metro-One]

Almost any subway, especially one that dips below sea level, will have water seepage issues. There is now way to completely stop it, just mitigate it. As i said, if one were to stop the pumps, many parts of the New York subway system would be completely under water.

[jsbertram]

Originally Posted by Zassk

^ Oh, I'm surprised there aren't drains/pumps or something at each end of the bored tunnels to prevent runoff heading in. I guess Dunsmuir tunnel doesn't get exposed to this problem, and the cut & cover sections don't have any low points.

The Nov 13th Buzzer has an article about the late-nite shuttle between Stadium Stn and Waterfront for the next 4 weeks. One track is being shut down so work crews can repair seepage that has been a problem since the CPR Dunsmuir tunnel was rebuilt to handle SkyTrain. 25+ years of seepage has caused a lot of rusting and concrete spalling. I believe I saw a report on BCTV (Global) a few weeks ago. The reporter was escorted into the active tunnel & shown the issues.

It's appalling that in order to save a few bucks, someone decided that a sump-pump at the bottom of the tunnel wasn't needed. It doesn't matter how long, wide or deep False Creek is, nor how deep the tunnel is dug under the False Creek bottom; a Tunnel under water will inherently have leaks, and it is proper engineering to allow this leakage so that the water pressure above & around the tunnel is kept close to normal.

If I remember correctly, the Chunnel was designed specifically to allow water to seep between the chalk marl and the concrete rings that make up the tunnel, and every few hundred feet along the length of the tunnels there is a sump pit & pump to remove this water.

This isn't an issue only with the False Creek tunnels, as I recall in Sept seeing water trickling and pooling in the tunnels between King Edward and the first curve around QEPark. I pointed it out to a friend who knows more about hydraulic & civil engineering than I do, and was told "that's normal seepage & should be expected". I would have expected the tunnel's exteriors would have been waterproofed so the seeping water would have to go around the tunnel & into sumps under the tunnels.

Can we get Mike Holmes to do an inspection of the C-Line & growl at everyone when he finds sub-standard work?

[TransitJack]

Originally Posted by jsbertram

The Nov 13th Buzzer has an article about the late-nite shuttle between Stadium Stn and Waterfront for the next 4 weeks. One track is being shut down so work crews can repair seepage that has been a problem since the CPR Dunsmuir tunnel was rebuilt to handle SkyTrain. 25+ years of seepage has caused a lot of rusting and concrete spalling. I believe I saw a report on BCTV (Global) a few weeks ago. The reporter was escorted into the active tunnel & shown the issues.

It's appalling that in order to save a few bucks, someone decided that a sump-pump at the bottom of the tunnel wasn't needed. It doesn't matter how long, wide or deep False Creek is, nor how deep the tunnel is dug under the False Creek bottom; a Tunnel under water will inherently have leaks, and it is proper engineering to allow this leakage so that the water pressure above & around the tunnel is kept close to normal.

If I remember correctly, the Chunnel was designed specifically to allow water to seep between the chalk marl and the concrete rings that make up the tunnel, and every few hundred feet along the length of the tunnels there is a sump pit & pump to remove this water.

This isn't an issue only with the False Creek tunnels, as I recall in Sept seeing water trickling and pooling in the tunnels between King Edward and the first curve around QEPark. I pointed it out to a friend who knows more about hydraulic & civil engineering than I do, and was told "that's normal seepage & should be expected". I would have expected the tunnel's exteriors would have been waterproofed so the seeping water would have to go around the tunnel & into sumps under the tunnels.

Can we get Mike Holmes to do an inspection of the C-Line & growl at everyone when he finds sub-standard work?

There are sump pumps throughout, including under False Creek. It's only natural to expect that occasionally issues arise from such devices.

[CLC]

After another "heavy" rainfall overnight, is there any disruption to Canada Line service this morning?
(I have avoided Canada Line for some time now, but that's due to another reason: daily overcrowded #49 route that I use to connect to it)

in fact I never find Vancouver rain "heavy", it is simply quite lame, even up to 100mm in 24 hours for Pineapple Express rainstorm here is no match to 100mm per hour torrential rain found in tropical or sub-tropical climates

[ravman]

what is the current ridership number?

[jsbertram]

Originally Posted by ravman

what is the current ridership number?

I suspect that Hansen was thinking of the 1st days' figure when it was free & full of lookie-loos. Even then, I don't think it cracked 100,000.

I doubt he's actually used it unless it was a photo-op.

[jsbertram]

Originally Posted by Smooth

So the worker basically just set it to magnetic north instead of true north? I could see how someone might make that mistake. I'm sure lots of people don't know that there's a difference.

I just saw CMDT working on the mis-aligned compass.

On my way out of the VCC station, I saw that they were just leveling the new concrete. An hour later when I was going back to VCC Station, they had just pulled the compass out of the new concrete & were washing off the concrete that was stuck to it. Then they started digging out the newly-poured concrete.

Any idea when the mis-aligned compass at Cambie/ Broadway will get repaired?

[mr.x]

Originally Posted by Axe

The tunnel is below sea level. It goes under flase creek There will always be water in the tunnel. No way to stop water. water seeps though Concrete as it is porous.

Well yes, but i didn't think there would be that much water seeping in through the concrete...

[jsbertram]

Originally Posted by mr.x

Well yes, but i didn't think there would be that much water seeping in through the concrete...

If you look closer, the seepage appears to be between the rings of concrete that make up the tunnel. No matter how tight the rings are pressed together by the TBM, there will still be a enough of a gap to allow water through.

[agrant]

Same thing will happen to buildings here if the proper steps aren't followed. You're supposed to apply a sealant and/or some sort of impervious material (can't remember what it is called), to the outside of the foundation, as well as installing perimeter drains around the building. Otherwise you could end up with a little lake inside...

The tunnel sections are probably sealed with something on the outside, but that still leaves the joints. And I think that is where I've seen the water coming through from pics I've seen.