Coxwell Sanitary Trunk Sewer Bypass

[44 North]

Things are moving along:
...
The Coxwell Bypass Tunnel (CB Tunnel) is to be constructed over the next 5 to 6 years and will form the backbone of the City's wet weather flow control programme to protect water quality in the Lower Don River and the Inner Harbour. The Coxwell Bypass tunnel will provide redundancy for the existing Coxwell Sanitary Trunk Sewer and eventually accept a series of connections to intercept storm and Combined Sewer Overflows. The CB tunnel is proposed to be a 6.3 m (finished inner diameter) tunnel lined with precast tunnel segments, beginning at the City's Ashbridges Bay Wastewater Treatment Plant and running 10.6 km to Coxwell Ravine Park. In addition to the tunnel, there are five (5) vertical storage shafts (20m and 22m diameter). The tunnel is to be constructed at a depth of approximately 50 to 60 m in Georgian Bay Shale.

Okay, interesting. Remember stumbling on this project a couple years ago and being astounded at how massive it is. I was under the impression it was to be built over the next 25yrs, not as a one-shot deal for the near-term. Also interesting that this is a real deal tunnel with precast segments, and not just a crude shotcrete one. I wonder if the TBM could be used afterward for RL-related work?

 

[Northern Light]

A few notes to offer.

1) Yes, Toronto Water has been seeing, theoretically, significant increases in funding with increases in the range of 9% annually for about a decade.

2)This has not increased revenue anywhere near original projections, due to greater water efficiency. Uptake of low-flow toilets, showerheads, High-Efficiency
dishwashers and washing machines has greatly reduced per capital consumption.

3)This by-pass was originally conceived of as a storm-water bypass, with ability to capture some sanitary overflows from CSOs (combined sewer overflows).
It is my impression ( I may be wrong) that this is now being sized to handle a catastrophic fail of the Coxwell Trunk Sewer.

This was originally contemplated as being done by twinning said sewer under Coxwell.

I may be mis-reading things.....but I don't see any indication of that project moving forward at this time.

 

[DSC]

This HUGE contract is about to be awarded. (Over $400 million dollars.) see http://app.toronto.ca/tmmis/viewAgendaItemHistory.do?item=2018.PW27.2

 

[tstormers]

Just thought I'd add 2 photos I got of part of the works being down at the East Harbour site regarding the Bypass.
Cheers,

 

[44 North]

You can see a nearly identical concrete ring when passing over the viaduct in Rosedale Heights' playing field. These shafts will be enormous.

 

[AlvinofDiaspar]

You can see a nearly identical concrete ring when passing over the viaduct in Rosedale Heights' playing field. These shafts will be enormous.

There are some extant examples in the city:

https://www.thestar.com/news/gta/20...-safe-from-fatbergs-to-preventing-floods.html

AoD

 

[innsertnamehere]

I had a chance to visit an access shaft for a sewage project in Mississauga about 5 years ago, at Dixie and Lake Shore. It was absolutely massive. Probably 60ft wide and 100ft deep.

 

[nfitz]

I wondered why this thread was active again, after nearly a decade.

Technically this Bypass tunnel is a different project than the original bypass tunnel, which was to replace a failing section of the Coxwell Trunk Sewer (near station CX-1 below).

This is more of a twinning than a bypass. Perhaps they found the word bypass less controversial!

Here's the map from the contract award report that DSC linked back in February!

 

[WestEnd]

https://www.google.com/amp/s/www.cbc.ca/amp/1.5396886

^ I believe this project was already started years ago... so why the re-announcement?

Would love to hear from the group, but I assumed that the multiple stages would be staryes up at the same time.

 

[AlvinofDiaspar]

https://www.google.com/amp/s/www.cbc.ca/amp/1.5396886

^ I believe this project was already started years ago... so why the re-announcement?

Would love to here from the group, but I assumed that the multiple stages would be staryes up at the same time.

I think today is the official start of TBM tunnelling.

https://twitter.com/x/status/1205904072630558721

AoD

 

[WestEnd]

I think today is the official start of TBM tunnelling.

https://twitter.com/x/status/1205904072630558721

AoD

Ah, so that specific operation has started; I see now. This is a Great project, but things like this never get the votes it'll deserve.

 

[salsa]

https://www.google.com/amp/s/www.cbc.ca/amp/1.5396886

Plans put in place by previous administrations over the years said that by 2038, waste water dumped into the lake would finally be as close to zero. "I just felt that was far too long," Tory said, adding his goal is to make that a reality in about half the time — within 10 years.

Good on mayor Tory for accelerating this project.

 

[Northern Light]

Ok, time for a good look at one of the sites involved. The one we can all see from Line 2, or the Viaduct!

Photos taken February 25th, 2021

 

[Northern Light]

A couple of not super revealing shots of the tail or south end of this project, at the Ashbridges Bay Sewage Plant.

Pictures were taken from the Pumping Station high land point; and and the crest of the Skateboard Park.

The Hoarding was so tall on the Pumping Station side I still couldn't see into that site at all!

So perhaps our drone-owners would like to take that on!

Photos from February 27, 2021.

Man that water tower needs new paint underneath the tank!

 

[robmausser]

Now THIS is the sexy infrastructure I came to Urban Toronto looking for. Sewer bypasses! I mean, you can see pics of them on all the Toronto Instagram accounts, but I like to find the nitty gritty details too.

Ok sorry /s I couldnt resist.