Heard an ironic, and somewhat ridiculous story (link here) on the radio just now, that water conservation regulations in Los Angeles - where lawn watering was prohibited on some days, and allowed on other days - lead to pressure spikes and troughs that lead to widespread failures (101 failures in a year, more than double the previous years' records) in cast iron pipes, most of which were 30 years old or more. Human behavior, it's so predictable!
LA residents, in fear of fines - and some wanting to be environmentally conscious - didn't water on the restricted days, and then the allowable days, BAM, everyone opens the spigots around town. Cast iron's LCF (low cycle fatigue) properties are pretty pathetic, from an over-all comparative material strength perspective. Couple this low resistance to cyclical stresses with an aging, corroding, under-capacity metropolitan water system built on massive fault lines, and it is no wonder the number of failures are climbing.
1 year ago