@Xiefie,
You've just identified the nature of the problem. Pipes don't normally freeze, so why bother putting up new construction that will prevent it from happening!

I remember water mains bursting in or around Beichen this year, last year and the year before (I don't know about before then because I lived in a different area). The solar heater pipes seem to burst every year... they are usually thin and often totally lack insulation. This failure to admit to there being a problem is part of the reason that China is holding back it's own development. This time it really is cultural.

@AlPage

Food for thought: EarthquakeS aren't common in KM either But does happen. Just hope I'm not still around When it hits.

@ricsnap: I think the reason for no central heating south of the Changjiang (Yangtse) during the Mao years was to save natural resources (coal etc.) for development back when the country was very, very poor. Seems to me it made sense - then - not sure about today, what with pollution everywhere (coal as basis for development, cars everywhere, etc.), but I'd rather have it than a car.
I called my landlady and she'd been around the xiaoqu where I live, said not water pipes broken, though she didn't get into my flat. Surprising, as I live in the oldest or 2nd oldest xiaoqu in Kunming, built about 1993. Not sure what this has to say about more modern xiaoqus where the pipes have broken.
Thanks for the info, folks.