Water Main Flushing

Overview

Water main flushing is one of the most important things we do. The Utility typically does a system-wide flushing each year in late-spring or early-summer, and dead end flushing two times a year.

During system-wide flushing, the flushing crews work at night from 10:00 pm to 6:00 am.  When flushing dead-end water mains only, the flushing crews work during the day from 7:00am to 3:00pm. Public Notice is posted in the La Crosse Tribune as well on the Water Utility website advising of the locations of planned water main flushing activities.

A precise schedule of flushing operations is difficult to determine more than a day or two in advance. We ask for your patience and understanding during this critical main cleaning process.

Why have a Water Main Flushing Program?

Water main flushing improves water quality and minimizes discoloration. The City of La Crosse water mains are systematically  flushed using a mostly-conventional procedure starting near the wells and then working out and into the system from those locations. The procedure is performed in warm-weather months and involves the systematic opening and closing of hydrants, one section of main at a time, to force the water through the pipes at high velocity, removing accumulated mineral sediment.  Hydrants are flushed until the water is clear. The operation can take from a few minutes to over an hour, although most last about 30 minutes or less.

Conventional flushing removes accumulated sediment from pipes and involves the flushing of multiple hydrants at a time but and does not involve turning the valve-off on individual sections of main.

How Will Flushing Affect Water Service?

When flushing crews are working close to your residence or business, you may experience periods of very low pressure or even a complete stoppage of service. We attempt to notify customers in advance if flushing is expected to result in a complete water outage, but such outages are rare. Flushing operations may also lead to discolored water, which can be drawn into homes and businesses if the water is being used during or immediately following the flushing. Such events should affect customers for a few hours at most. The discoloration is caused by iron (red color) or manganese (black color) particles being dislodged from the water main which can stain porcelain and laundry. If discoloration occurs, open the cold tap nearest the water meter—usually a basement sink—to full flow until the water runs clear. In some situations this may take 5 to 10 minutes. It is also advised that you make sure your water is clear before doing laundry or other projects for which discolored water could cause problems.