Midday today a sprinkler head in the basement garage got damaged. This set off the building’s fire alarms and let a lot of water into the basement. I also suspect that the rush of water coming onto the building because of the broken sprinkler is what stirred up sediment in the water lines and resulted in brown water complaints midafternoon.
The sprinklers have been fixed and the water coming out of people’s faucets has cleared—if yours hasn’t, let your cold water run for a few minutes.