“Once you build it well, you’ve done well”
By Neale McDevitt
Saeed Mirza has been warning federal, provincial and municipal officials about the looming failure of our infrastructure since 1985. Early on, his warnings of impending tragedy were met with the same looks usually reserved for Chicken Little. But no longer – especially after the 2006 collapse of the de la Concorde overpass in Laval killed five people and seriously injured six more.
Today, the 45-year veteran of the Dept. of Civil Engineering and Applied Mechanics, Mirza is the media’s go-to expert for all things infrastructure in Canada. And while the honorific Emeritus Professorship that he now holds often suggests the slowing down of some professorial careers, Mirza is just as passionate, just as actively involved and just as opinionated as ever before – as witnessed in this recent interview with the Reporter.
In a word, what is the state of Canada’s infrastructure?
Most of it was built after World War II and it was done in such a rapid way that the quality control was very poor. We see the results today in the sorry state of structures like the Champlain Bridge and the Turcot Interchange.
Is there one main problem plaguing our infrastructure?
There’s not a single problem, but the issue of improper drainage design has had a negative impact on many of our structures, especially the transportation facilities.
Our roads for one. According to the City of Montreal, they fix about 50,000 potholes a year.
What are the mechanics of a pothole?
The basic problem is we have never really designed our roads with proper drainage for rainwater or snowmelt. Water diffuses into the pavement and gets into the base, sub-base and subgrade, where it accumulates and forms little pockets of water. During winter, these freeze, and as ice is formed, it expands by about nine per cent. Ice has tremendous strength and it will resist the weight of trucks passing over it.
But by late-February, early March, that pocket of ice melts and since water has no strength, it collapses when vehicles pass over it, and with each passing vehicle, it gradually disintegrates and the material is lost, forming a pothole.
Isn’t this the normal bane of countries with harsh winters?
Not at all. Countries like Sweden, Norway, Finland – their roads are much better than ours because they have proper drainage. Unfortunately, the City [of Montreal] seems more interested in filling potholes than preventing them – and Mayor [Gérald] Tremblay has a fancy gadget that fills the potholes. However, many of these repairs do not last long – they have to be repaired again, representing a serious financial loss of taxpayers’ money. But if we provided proper drainage at the beginning, these problems would not arise, or at worst, they would be minimized.
Is drainage an issue with the Champlain Bridge?
Yes. Improper drainage means snowmelt and salt flow transversally over the bridge deck and pour over the outside girders, causing serious degradation of pre-stressing tendons in these girders. The problems with the longitudinal flow (parallel to the bridge axis) have seriously damaged the girder ends, the pier tops and the piers themselves.
Can’t we just make some quick fixes to keep it operational?
If you have a dying patient, you can only do so much. Right now they are trying to replace the hips on a patient with terminal cancer… you can improve their quality of life for a few years, but the end is still coming.
What is the average service life of a bridge?
These days, it must be at least 75 years and we can certainly make it last longer. The Confederation Bridge [linking Prince Edward Island with mainland New Brunswick] has been designed for a service life of 100 years. And I’m hoping it will still be there in 150-200 years because of its careful design.
The Champlain Bridge was built in 1962, how much longer will it last?
If we continue like this, it could perhaps last between 10-15 years – provided we don’t get hit by a large earthquake. I have serious concerns about the steel reinforcement between the pier and the pier cap; it may have been seriously corroded and it may not be able to resist the large lateral shear force caused by the earthquake. The Champlain Bridge is a lifeline structure so it should be able to withstand the force of a major earthquake, and it must remain operational after an earthquake for emergency services.
And what about our water?
Montreal’s system is so badly deteriorated in some parts that we are losing between 30-40 per cent of purified water. If the City was a large corporation, it would have gone bankrupt by now. The situation is similar in many older North American cities.
Our water-supply system is full of perforated pipes and our sewers are also leaking in close proximity. If something gets into our water supply, what will be the effect on our health and what will be the cost? The water supply should be such that it doesn’t harm us, as it did in Walkerton, Ont., and North Battleford, Sask., and many other places. Out of sight, out of mind, I’m afraid.
How much would it cost to fix things properly?
In late 2007, a detailed survey of Canada’s municipal infrastructure by McGill and the Federation of Canadian Municipalities showed we needed $123 billion just to upgrade our municipal infrastructures to an acceptable level – that doesn’t take into account the highways and bridges and other structures under provincial and federal jurisdiction. This estimate does not account for new infrastructure needs in the various communities that amounted to another $115 billion.
Within the industry what needs rethinking?
As engineers we have to change our professional philosophy. Engineers design and build, but they do not provide a detailed maintenance strategy for their systems. We need a paradigm shift and must change the present philosophy of “design, build and forget” with design, performance and maintenance.
When you or I buy a car, it comes with a detailed owner’s manual on how to maintain it and enhance its longevity. But we build systems worth millions and millions of dollars that come with no such maintenance manual. We need to change this serious flaw immediately.
So issues of sustainability should be of more concern?
Yes. And the University has a responsibility to offer detailed courses on infrastructure. Not simply to teach students how to build structures, but also how to maintain them and how to renovate and rehabilitate the existing deteriorated structures in a sustainable and cost-effective manner.
I would like to see sustainable development included as an integral part of each course, not just as a separate entity, but to run right through the curriculum in every course.
Once you build it well, you’ve done well. In most cases, there never is a second chance.