After a major feeder water main break plunged Calgary’s water supply into a critical state, city officials are now asking Calgarians to use 25 per cent less than they did yesterday, sounding the alarm that the city is at risk of running out.
The Bearspaw south water main — which is 11 kilometres long and as wide as two metres in parts — suffered a break Wednesday night that left hundreds of homes and businesses in the city’s northwest without water.
Just before 7 p.m. Wednesday, the break caused streets to suddenly flood in the Montgomery area around Home Road, forcing the closure of several roads and intersections, including 16th Avenue in both directions.
Gosh, the conservatives are doing such a good job managing provincial services!
So this is actually happening about 100m from my house, my partner is currently staying with a friend so she can watch their kid because that friend works for the Calgary Emergency Management Agency (CEMA) and is working night shift doing analysis and mapping. I also used to work as a pipeline integrity engineer (but being a dirty hippy I took a catastrophic pay cut to move into sustainability consulting a few years ago). What I’m trying to say is that I am up close and personal with this in a way few people are.
Calgary and Edmonton are less conservative than you think - the cities mostly vote NDP and the UCP gets elected by the farmers and oil field workers. The mayors of both cities are at constant war with the provincial government who just introduced new rules to keep the cities from being able to work with the feds without permission. Alberta is still way more conservative than I like, but so are a lot of provinces.
Now - the break. This is the largest section of the main artery of the municipal water system. It’s made from rebar reinforced concrete, is 2m in diameter, and was built in 1975. With steel pipe there’s lots of very cool and sophisticated tools you can use for inspection. You can run ‘Smart Pigs’ down steel pipe which can use ultrasonic sensors to check for internal and external pitting and you can use magnetic flux leakage to inspect for cracks. Concrete is brutal to inspect. The city recently installed acoustic monitoring in this area; these are basically microphones that are trying to listen for cracking or debonding of the concrete from the rebar. This pipe is next to/under the Trans Canada Highway. So you are trying to listen for micro-cracking in the middle of a speed-metal concert and most of the damage that caused this would have accumulated over decades - there’d be little to no warning.
Integrity engineering is about risk and risk is a combination of how likely an outcome is and the consequences of that outcome. With potable water, the consequence is normally pretty low. Water distribution systems normally leak like crazy because the money required to make them perfectly water tight is way better spent on social services. This particular site was always going to be catastrophic if it failed, and the city was doing everything they could to try and manage the risk. Simultaneously, they are trying to manage it without shutting down one of the key road arteries, without spending millions of dollars unnecessarily, and without the risk to people and infrastructure that come with major earthworks in congested areas (look at what’s happening with UBCO’s construction in Kelowna).
Calgary actually has a lower loss rate in our water distribution system than the majority of major cities.
I would love to call the water department incompetent since I currently have a lake next to my house, haven’t had a shower, done laundry, or washed dishes in three days - but having gone to technical presentations by the city’s water system integrity team, and having some expertise in the field, I have mad respect for the people who manage our water system.
This is probably the most relevant voice I’ve seen on Lemmy that wasn’t in tech.
Although it seems like building it under the highway was not a great move. Was there some benefit like the earth being dug up anyways when they decided to put it there?
Aww, thanks!
For location, it’s balancing competing interests again, spiced with the excitement of trying to see 50 years into the future.
A 2m pipe takes up a lot of room and very rarely gets dug up. Roads are the easy place to put them. Otherwise they tend to end up under buildings as development goes on. Alternatively, you would need massive setbacks from the road to businesses and homes. People also like to do things like build basements which are generally deeper than water and sewer lines. Water and sewer are generally 2.5m down to minimize freezing issues in winter. My basement goes down 3m and there’s a sump below that. Bigger buildings with multi-story parkades can go seriously deep. As a result, a lot of utilities, which should rarely need excavation, go under the road.
Subways often run along roads for similar reasons. Vancouver is expanding their subway (sky train), and it mostly follows roads because its cheaper and easier to dig down and burry it than to bore tunnels (see Toronto’s nightmare with stuck boring equipment).
I did smart pigging and challenging pipeline stuff years ago and reliability engineering up to a few years ago, also got out of o+g for similar reasons.
Totally agree and just adding on to all that, even if it was steel, I’m super willing to bet it’d be impossible to run a normal pig through, so much infrastructure is just full of diameter changes, unbarred tees, really tight back to back bends etc, I can only imagine the challenges to pig a line like that, let alone costs involved with specialised tooling and support work, I know some people who did a short run through a downtown core on a gas main and that needed hot taps, road closures and a really special pig for what was less than a kilometre.
Supposing it could be pigged without blowing up their entire maintenance budget, I wouldn’t want to touch any of the water coming out of that line during operations, so you’d also interrupt water service for a while, having a solid reaction plan really would be one of the best solutions.
Could they use a crawler with visual inspection? It’s not as good as ultrasound because it will only see surface breaking stuff if it’s big enough… But it’s still better than no inspection at all, right?
Crawler is possible, still need to get into the line though, I recall there being a few options for tethered camera crawlers meant for sewer inspection. Visual does have drawbacks, can’t really size defects, as far as I recall it’s difficult to get full coverage and cleanliness is even more important, and you’d general need the operations on that pipe to cease. Ideally you want your inspection regiment to allow you to know something’s coming and be able to plan for it, example if I start seeing vibration increasing on some bearings, I can monitor them and start planning for their replacement on a scheduled shutdown.
No inspection is actually a totally valid mitigation plan for some assets. Criticality and failure consequences play a large role in that as well as the feasibility to inspect. Electrical devices for example follow random failure patterns and historically don’t really have a timeframe between failure initiation and functional failure that’s actionable, so a mitigation strategy I’ve seen done is something like hot spares if it’s critical. On the other hand, something that is inspectable but won’t result in high consequence of failure (death and injury are the things that are usually weighted heavily) it might not be worth inspecting either, it’s all about trying to get the most out of limited maintenance budgets.
Just a heads up for anyone looking for updates!
Why are they concerned? They have plenty of oil to drink
