Dirty tap water

Hi all:

I woke this morning to dark brown water from both the hot and cold taps in my building. It's now down to a light yellow. I called 311 and reported it in case there's a water main problem, but is anybody else having this problem?

Was there Fire Dept activity or a running hydrant nearby? Usually after a big FDNY event, or an open hydrant running for a long time, the sheer pressure dredges up all kinds of gunk...

The cause may also be internal to your building: Plumbing work. Cleaning a wooden tank. Etc.