Make Purple Your Favorite Color!

Purple pipes offer an easy way to distinguish recycled water from the potable water distribution system.

Purple pipes offer an easy way to distinguish recycled water from the potable water distribution system.

by Alysa Suero

What comes to mind when you think of purple? Likely you conjure images of grapes, flowers, or your favorite socks. How about a purple pipe? Most states require pipes to be colored purple if they carry reclaimed water. Reclaimed water is an important component in water conservation and one that is rapidly gaining in popularity for many uses.

Reclaimed, or recycled, water is highly treated wastewater that’s used again for a variety of purposes such as irrigation, industrial processes, and cooling towers. Often the treated water flows through purple pipes to the end user. Purple pipes offer an easy way to distinguish recycled water from the potable water distribution system.

There are many benefits to using reclaimed water. Using it for golf course irrigation or toilet flushing, for example, reduces the demand on our fresh water resources, reduces the nitrogen loading to the watershed from the wastewater treatment plant, and offers the end user a financial savings since it’s often cheaper to use reclaimed water than to operate a ground water well or purchase potable water from the local water supplier. It also saves energy that would otherwise be used to treat raw water at a drinking water treatment plant.

Reclaimed water in those purple pipes isn’t just for physical processes, either. Highly treated reclaimed water can be used to indirectly augment drinking water sources. In the mid-Atlantic, the Upper Occoquan Sewage Authority has been discharging recycled water into a stream above the Occoquan Reservoir since 1978. The sewage authority can send as much as 54 million gallons per day to the reservoir ensuring that a potable water supply source is consistently ready to serve Fairfax County and the City of Alexandria, Virginia.

As an individual, you don’t need a purple pipe to recycle water in your own home. Try watering your garden with rain water collected in a barrel. Feed your houseplants with water from your half-full water glass instead of pouring it down the drain. Every time we reuse water, whether through purple pipes from a wastewater treatment plant or even in our own home, we’re taking another step to conserve our precious water resources, and that’s a “plum” reward we can all appreciate.

About the author: Alysa Suero is a licensed professional geologist in the Water Protection Division’s Drinking Water Branch. When not in the office, Alysa, who was recently married, enjoys cooking, family game night, organizing closets, and caring for her two rabbits.


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