What is Water Main Flushing?

Water main flushing is the process of cleaning or “scouring” the interior of water distribution mains by sending a rapid flow of water through the mains. Distribution mains convey water to homes, businesses and hydrants in your neighborhood.

Flushing helps maintain water quality.

The water entering our distribution mains is of very high quality; however, water quality can deteriorate in distribution mains if the mains are not properly managed. That is why flushing is important. Flushing removes sediments from the mains. Sediments are undesirable not because they pose health concerns but because they can degrade the “acceptability” of the water by affecting its taste, clarity or color. Flushing helps remove “stale” water in areas where our system may dead-end instead of being looped. Also flushing helps to maintain chlorine residuals throughout the distribution system.

How much water is used to flush mains?

That depends on many factors, such as main size, system pressure, the amount of sediment and the ability to dispose of the water used in flushing. A significant amount of water is used to flush mains; using this water may seem to be inconsistent with water conservation, a goal to which Spanaway Water is dedicated. However, protecting water quality is also a critical goal of Spanaway Water, and the trade-off is to conduct flushing, but using as little water as possible, while still being effective.

How often is flushing done?

Flushing is done every Tuesday. We begin in October and continue through April every year.

What can I do to prepare for flushing in my community?

• Draw water for cooking ahead of time.
• Store a large bottle of water in the refrigerator for drinking.
• Check for discolored water before using the washing machine or dishwasher.

Note: If your laundry becomes stained. DO NOT USE BLEACH AND DO NOT PUT YOUR LAUNDRY IN THE DRYER. Rewash clothes immediately using more detergent or a heavy-duty detergent and add a rust remover. Most rust removers can also be used on stained fixtures.

For more information see our flushing brochure.