RIVERTON, Wyo. (AP) — Encana is constructing a facility in central Wyoming that will treat up to 1 million gallons of water a day that comes with oil and gas production.

Encana says the facility between Casper and Riverton is the third largest of its kind in the world. It partnered with GE and Dow on the facility and held a groundbreaking ceremony on Friday.

Officials say the water treatment plant will effectively clean produced field water to about the same purity as mountain spring water.

Some of the cleaned water will be used for field operations, while the rest will be piped into Boysen Reservoir. Frequent tests will be conducted at the facility and discharge points, to assure water quality meets state requirements.