Pipe Materials in Calgary Presentation Slide #30

In 1990, we had about a third the PVC we have now; we've gone from 500km then to 1400 now. And we've had 17 breaks on all of it over those ten years. They all fit on this one slide.
The top eight, in blue, are actual repairs to PVC that had no visible interference, though construction errors like bending it or placing it on a large rock were usually involved.
The middle one was a leak between PVC and PDI where the clamp between them was not on right.
And the bottom eight are all related to service taps; either they pulled out, or a crack in the PVC spread out from the tap site. You can never have perfect workmanship.

The number 17 glosses over that we've probably had at least 17 more breaks on PVC during construction of it or near it. There's no question that it's lower strength does render it more vulnerable to construction breakage from tamping too hard, or from shifting the soil it is in during nearby excavations. But, really, that's quibbling about whether it has 1% or 2% of the breaks that we've had from metallic mains.