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Castle Rock to implement 'toilet to tap' surface water treatment system

Posted at 5:37 PM, Feb 20, 2019
and last updated 2019-02-21 10:46:05-05

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DENVER — As Colorado’s cities grow, municipal leaders are finding creative ways to protect resources, like water. The City of Castle Rock is doing just that by planning to purify sewage water into drinking water.

Four and a half million gallons of surface water a day in the winter is treated at the Plum Creek Reclamation Authority's wastewater treatment plant in Castle Rock.

Mark Marlowe, the Director of Castle Rock Water, said as soon as next year, the city’s wastewater purification system will turn toilet, drain and sink water into drinkable tap water.

"Tap water is great water, and I would argue just as good as spring water and in many cases better than bottled water," said Marlowe.

Between growing populations and changing climates, water sources are expected to shrink, so the city has to get creative.

Greg Baker with the City of Aurora said there have been no complaints since the city implemented the system that recaptures river water to provide drought insurance.

"All water starts someplace. All water ends, and it goes into a giant circle and starts over again," said Baker. "I think the challenge here for most people is that they have a connection between something that is not pleasant to something that is vital for safety and health."

Back in Castle Rock, treated wastewater is released into East Plum Creek and then will be recaptured and purified once more before we drink it from the tap. The concept is nothing new.

"Everyone lives downstream of somebody and they're reusing that water all the time," said Marlowe.

Now it’s just deliberate.

"We're doing everything we can to fully utilize every drop we can before we have to go out and find more water to meet a growing population," said Baker.

Castle Rock Water will host an open house Feb. 23 from 10 a.m. to 2 p.m. at the Plum Creek Water Purification Facility, 1929 Liggett Road, to learn more about how to reuse water is a safe, sustainable and economical water source for the community.