Pipe Materials in Calgary Presentation Slide #15

I'm just going to switch colours at random with each slide to highlight the added breaks. 1974-75 was the turning point for us. The trend continued to worsen. It wasn't just that our break rate had gone up 50% in five years, it was that much of the increase was concentrated in one area where the public was understandably up in arms - and that a lot of the main affected was very young. We did understand it was the corrosive soil and not anything different about the DI from CI, but still it was plain that Something Had To Be Done.
The Chief Engineer of the time, Jim Bouck, eventually became the manager and my first boss, and I interviewed him in retirement. The first-blush judgment was that they were having about as much trouble with PDI as with bare DI, and though they continued to use polywrap, they were almost frantic to find something better. The PVC industry and the developers were already pushing for PVC, but there was no AWWA spec for it at the time, and Jim wanted to wait for that blessing before committing to it. In 1973, that was still five years away, so we turned to YDI as a stopgap.