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Pipe map by material

The two materials this crisis made us switch to, are shown here on this other map from my GIS, which colours the pipes by material type. It's also a kind of history. The older centre of town is mostly still dark blue, for old thick-wall cast-iron, and magenta around it, for the later thin-wall cast iron. Light blue is the ductile iron that corroded so quickly. The yellow is also ductile iron, but we call it a different material type entirely, YDI, for yellow-jacketed ductile-iron, a corrosion-protected product invented by the oil industry. We knew it well because Calgary is an oil city. We took the lead in adapting it for the water industry. And the newest ring, the green, is the PVC we've been putting in for over twenty-seven years now.

© Roy Brander, P.Eng 2003