Hydrant Flushing Flushing of the Borough water mains is in April and October. During the month, this work will be done in the early morning hours between 11:00 p.m. and 3:00 a.m. This Operation will continue until the entire system is flushed. No flushing will be done on Saturdays or Sundays. The entire program should be completed in about one month. It is advised to allow the water to run for a few minutes each morning following our flushing to check for rusty water.