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Cities turn to grey water recycling to fight drought

Grey water can also be used for landscaping and gardening in places with proper regulations. California and Arizona are just two states allowing it.
Posted at 9:05 PM, Feb 24, 2023

The city of Fort Collins, Colorado is working to be an example for other cities to implement their own grey water systems. Experts say it's just one solution to making better use of our water.

Water scarcity and drought issues may sound like colossal undertakings, and experts say they certainly can be.

As Mayor of Fort Collins, Jeni Arndt faces big questions about it.

"We are becoming fundamentally drier. So how are we going to take an actually shrinking resource in an expanding population and still serve people well?" Arndt said. "When we save water from not being up to today's potability standards, we're really saving energy that it takes to refine that water."

Last summer, the city of Fort Collins began allowing grey water systems to be installed in new buildings.

"It's really for new buildings — if someone wants to develop a housing development or build a new home, then can plumb from their shower to their toilet and then out," Arndt said. 

Here's how it works: A grey water system captures gently used water coming out of bathtubs, showers and washing machines from homes. The water is essentially filtered and then used in toilets. This gives the water a second use in the household instead of going straight into the sewer system.

Grey water can also be used for landscaping and gardening in places with proper regulations. California and Arizona are just two states allowing it.

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"We're not allowing outdoor use of grey water because what we're really trying to do is keep the consumptive part of water intact. If you put it out on your landscaping, it could evaporate and then you could have consumptive loss," Arndt said. 

Gary Wockner is the director of the nonprofit Save the Colorado. His group advocates for preservation of the Colorado River. He says implementing grey water systems can happen anywhere, but he points out there are limitations.

"The number of times you can use water repeatedly actually depends on water rights and water law," Wockner said. 

"And let me tell you there are very strict controls on these types of things because we really don't want waterborne illness," Arndt said. 

That is part of the reason they are still so few and far between.

"This [is] very rare that this is happening," Wockner said. 

While water scarcity is a global issue, experts say each community has a set of unique challenges.

"Think about what's right for your community, what your goals and your values are and then how you can pitch in to make that a reality," Arndt said. 

And regardless of where you are, implementing grey water systems like her city has done can take some pressure off of the over-reliance on freshwater resources.

"When there's a real need, humans will respond and I'm an optimist and I think we can really take care of our water-short future," Arndt.