Water main flushing is one of the most important things we do. Find out how our program puts Madison on the forefront of water safety and quality.

The 2019 Water Main Flushing Program began on April 8.

Water Main Flushing plans beginning MONDAY, NOVEMBER 4 (all flushing is daytime unless otherwise noted):

EAST (Area 8) -- North of Atwood Ave from Waubesa St to Winnebago St

EAST (Area 15) -- Stoughton Rd to the Interstate north of E Washington Ave

EAST (Area 25) -- West of the Interstate from Cottage Grove Rd to Commercial Ave

NEAR WEST (Area 27) -- Monroe St corridor from Regent St to Western Ave

WEST (Area 12) -- North of the Beltline from Whitney Way to Midvale Blvd

Please contact Shayne Santi at 261-9128 with any questions or comments about either the 2018 or 2019 flushing programs.

Flushing Schedule Map

More Information About Flushing

During the flushing season, most crews work between 6:00 a.m. and 4:00 p.m. Monday through Friday, with one crew (and sometimes more) working at night from 10:00 p.m. to 6:00 a.m., primarily in the central isthmus and university areas.

What is the Water Main (Hydrant) Flushing Program?

To improve water quality and minimize discoloration, City of Madison water mains are comprehensively flushed by a technique known as unidirectional flushing. 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 until the water is clear. The operation can take from a few minutes to over an hour, although most last about 30 minutes.

Unidirectional flushing differs from conventional flushing in that it involves the closing of adjacent valves and the use of a single hydrant per flush so as to isolate individual sections of main. Conventional flushing also removes accumulated sediment from pipes, but it involves the flushing of multiple hydrants at a time and does not include the valving off of individual sections of main, thereby diminishing the “scouring” efficiency. Conventional flushing is used in areas of the city where fewer minerals build up in the mains.

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.

A precise schedule of flushing operations is difficult to determine more than a day or two in advance. If you wish to be notified before work will be done in your area, please call Shayne Santi at 261-9128 or email water@madisonwater.org.

We ask for your patience and understanding during this critical main cleaning process.