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.
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.