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COLUMN: Hwy. 401 tunnel has echoes of Chunnel

'Construction is guaranteed to disrupt traffic flow — don't try to con us into believing it won't,' says columnist
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Premier Doug Ford has proposed a tunnel, 60 kilometres long and two lanes in each direction, under Highway 401 as the solution to Toronto’s traffic woes.

Let’s have a look.

A tunnel of similar length (50 kilometres) was completed in 1994 linking Great Britain (Dover) with France (Calais). I was living in the United Kingdom while the tunnel (called Channel Tunnel, or 'Chunnel,' in English, and Tunnel sous la Manche en Francais) was being discussed. Construction began in 1988.

This is an appropriate comparator to the proposed tunnel under the 401 — first, because of its length, and second, because it would be of similar diameter.

Drilling the tunnel had to be done exclusively from both ends because it was under the English Channel.

It will surprise nobody that the project took longer than anticipated. The final cost was almost twice the original estimate. One problem was the sudden doubling of interest rates late in 1988, saddling the contractor, Channel Tunnel Group and France-Manche, with unforeseen additional costs. (The original contractors went bankrupt, selling the operation to the present operator.)

Tunnelling was relatively easy; 45 kilometres of the route from England was through soft chalk. Helpfully, this chalk was impermeable to water — convenient for an under-sea tunnel. Just five kilometres of the distance on the French side was through “difficult geology” (trust the French to be “difficult”), but only 1.7 kilometres of this was under water.

Despite the mostly helpful geology, the final cost was an eye-watering $21.5 billion (Cdn.) in today’s money. Also helpful was the fact both ends of the tunnel were rural, leaving a lot of space for staging (parking of construction machinery and materials) and for removal of the excavated rock. On the English side, this was used to create a level seaside park.

Of course, staging for a tunnel under the 401 will have to be organized in a densely built-up area, and there is no conveniently unpopulated seashore nearby.

Two traffic tunnels, each 7.6 metres (25 feet) in diameter, plus a 4.8-metre (15.75-foot) service tunnel between them, were built. The latter was intended to carry repair vehicles or fire and rescue crews.

The British public clamoured for a motor vehicle tunnel. I wasn’t in France then, but I imagine they, similarly fond of cars, would have wanted that, too. In the end, the tunnel was built exclusively for electric rail.

The reasons are compelling and also apply to the Ontario case.

Top of mind was safety. Imagine a tunnel offering superbly uninteresting scenery, concrete, for 30 minutes. Some drivers would succumb to hypnotism or boredom and lose their attention. That would likely cause a crash, in a 50-kilometres tunnel.

Of course, dear reader, you wouldn’t lose concentration, but somebody would. How many crashes occur daily on the 401 through Toronto? (Oddly enough, Google was unable to answer that.)

Rescue personnel would mobilize, and then traverse, say, 20 kilometres of tunnel to reach the victim(s), and return the same distance. Helicopter evacuation is, of course, impossible in a tunnel. Then a tow truck or two would have to enter the tunnel from the opposite direction — traffic would be jammed behind the crash — to remove the damaged vehicle(s). At the crash site, would there even be room to turn around so the damaged vehicle(s) could be towed out?

Safety is a truly major issue.

In the Channel Tunnel, this was addressed by using electric trains travelling at 160 km/h, twice as fast as cars might go. (Train speed is limited to manage the pressure wave forming in front of the train. Once out of the tunnel, the Eurostar trains accelerate to 300 km/h.)

But cars and trucks do traverse the Chunnel using a train called LeShuttle. They drive onto special railcars at one end, traverse the tunnel, and drive off at the other end. The time taken is similar to what it would have taken drivers to travel the 50 kilometres in their own cars.

The safety of the system is incredible by road vehicle standards. There have been three or four fires — in 30 years. And the traffic is large. LeShuttle carried 2.6 million cars, 51,000 coaches and 1.6 million trucks (equivalent to 21.3 million tonnes of freight) — in a single year (2017). For the record, all the fires began on trucks aboard LeShuttle and all were extinguished rapidly.

In 30 years, one train stopped in the tunnel due to an internal electrical fault. The train was restarted within six hours. I doubt a vehicle crash could have been cleared faster.

Then there is temperature. I have driven through the Gotthard Road Tunnel between Switzerland and Italy. This is only 17 kilometres long; at the 80 km/h speed limit, this takes 13 minutes. If you open your window inside the tunnel, the temperature is 40 degrees Celsius. Fortunately, my friend’s car had air conditioning.

The warmth inside the tunnel is due to the heat created by vehicle motors. It is perpetually warm despite ventilation. And the Gotthard tunnel is only one lane in each direction. Imagine doubling the traffic.

The Channel Tunnel is three times longer than the Gotthard Road Tunnel, and would need mechanical refrigeration to keep it reasonably cool. Engineers calculated that even running highly efficient electric trains (electric motors are 90 per cent efficient), the temperature inside the tunnel would be 50 C.

To control temperature required Europe’s largest mechanical refrigeration system. If cars (30 per cent efficient) and trucks (45 per cent efficient) drove themselves through the tunnel, the refrigeration system would have had to be twice the size.

How about the effect on traffic of a tunnel under the 401? The ‘plan’ is to have two lanes in each direction. But the 401 through Toronto has up to 18 lanes in each direction, though parts are just eight to 10 lanes. Adding two might increase capacity just 20 to 25 per cent.

Considering also that building it is likely to take at least a decade, probably two, a 25 per cent capacity increase is modest. The proposed 401 tunnel project would need space for staging equipment, construction material, plus excavated rock. Construction is guaranteed to disrupt traffic flow — don’t try to con us into believing it won’t. Just look at the Eglinton LRT.

Value for money? Doesn’t Ontario have other pressing needs? Healthcare is troubled, largely due to a shortage of nurses. Schools need more teachers, and many need repairs, too. With electricity demand set to spike (for electric cars and heat pumps), more power must be built. The only way to fix the high cost of housing is to build more units. Developers prefer condos because they get their money out in a few years. Rental units need at least a decade of patience, and only government can provide that.

There you are, Mr. Ford — your feasibility study, done.

Don’t bother hiring consultants. They will tell you the same, but only after you pay them hundreds of thousands of dollars.

Barrie resident Peter Bursztyn is a self-proclaimed “recovering scientist” who has a passion for all things based in science and the environment. The now-retired former university academic has taught and carried out research at universities in Africa, Britain and Canada, and is a former NDP candidate. As a member of BarrieToday’s community advisory board, he also writes a semi-regular column.