Joint Water Purification Plant (JWPP)

The Joint Water Purification Plant (JWPP) is a cooperative venture between Arapahoe County Water and Wastewater Authority (ACWWA) and Cottonwood Water and Sanitation District. The plant provides potable water to 12,000 residents and 30,000 commercial employees.

Two Providers

The two water providers developed this cooperative project to meet their customers' increasing potable water demand and reduce reliance on deep groundwater supplies that will eventually be depleted. The plant provides up to 6 million gallons per day of treated potable water from the Cherry Creek alluvial aquifer, a renewable water source.

Lone Tree Creek Water Reuse Facility (LTCWRF)

The Lone Tree Creek Water Reuse Facility (LTCWRF) is a state-of-the-art Biological Nutrient Removal treatment plant that was commissioned on June 17th, 2008. The LTCWRF serves the Arapahoe County Water and Wastewater Authority (ACWWA), Cottonwood Water and Sanitation District, and the Inverness Water and Sanitation District. LTCWRF treats an average of 2.4 million gallons of wastewater per day.


Located adjacent to Cherry Creek Reservoir, a major recreational resource for the Denver region, this facility helps protect the reservoir’s water quality for swimming, boating and fishing by meeting one of the most stringent phosphorous limits in the country. In order to achieve this limit, the facility design incorporates a unique Advanced Water Treatment facility at the end of the treatment process.


ACWWA is dedicated to conserving our resources and has integrated a reclaimed water program which allows the re-use of our treated water for irrigation purposes. While some of the treated water is discharged out to Lone Tree Creek, during the summer irrigation season approximately half is returned to certain customers for irrigation use, helping to alleviate demand on our potable water supplies. For more information please visit the Regulation 84 page.