6. Sometimes it is necessary to flush while repairs are being made to relieve pressure on the main.
7. In order to make a repair, it is sometimes necessary to dewater a main and that is done either by flushing or using a drain valve.
8. As the distribution system infrastructure ages, it becomes necessary to flush more often to maintain water quality.
9. The Fire Department flushes every hydrant at least once each year to ensure that all hydrants are operational.