In our old apartment, the pipes would freeze during the winter during the night, and in the morning sometimes the water that came out of the tap was blue at first. We spoke to a plumber, and he believed it was due to "backwash" from the upstairs neighbor's toilet. However, our old landlord assured us that this was perfectly normal, and our water would be fine if we let it run for a while every morning.
Now we have a new apartment, and it appears the pipes have frozen again – when I turn on the tap, the pipes sputter and barely any water comes out. However, this time the water that comes out is brown. Is this normal? Should we demand that our landlord fix it – can it even be fixed?
I really don't like the idea someone else's poop flowing through the same pipes as our clean water (note: I don't actually know that that's what's causing it to be brown – could it be another reason?)
Best Answer
We're seeing here in action why backflow preventers (check valves) are mandated in various municipalities.
Blue water sounds like someone was using one of those toilet cleaner tablets in the tank, the system lost pressure due to the freeze blockage and siphoned the toilet tank till the fill tube on the ballcock was exposed. Not something I'd want circulating in my drinking water. It also could be copper sulfate from corrosion that occurs in copper piping, but that usually is only enough to stain sinks and tubs.
If the water is orangish brown, it may be that the stress from freezing has knocked a lot of iron rust loose in the pipes. Typically, there is always a major air gap between sewage and potable water (nigh impossible to get the toilet bowl to empty into the flush tank due to gravity and four inches of air the water would have to jump).
Your major worries with pipes freezing is that if they do burst, they can draw contaminated water back in if they're in places like flooded basements and the act of draining causes a vacuum within. At that point, you have bacteria contaminated water to deal with.
Your landlord definitely should be notified and should tell you what the water contaminant is.