Tapped: The Denver metro region sits at the center of one of the American West’s most complex and consequential water challenges. This series examines the interconnected systems that determine how the region secures, stores, and conserves its water while navigating the competing demands of fast‑growing urban communities and the increasingly unpredictable mountain snowpack that underpins the entire system.

Sterling Ranch receives water service from Dominion Water & Sanitation District, a wholesale provider serving northwest Douglas County. Currently, Dominion’s sole retail customer is the Sterling Ranch Community Authority Board.

Dominion holds permanent water delivery contracts with Aurora Water, the Water Infrastructure and Supply Efficiency (WISE) program and Castle Rock, connecting the district’s future water supply to other regional water authorities. 

Under those agreements, water is diverted from the South Platte River, transported through Aurora’s tunnel system and routed to Dominion’s jointly operated Larry D. Moore Water Treatment Plant. 

To support future growth, expanded aquifer well connections are currently being designed to connect to existing infrastructure. To compensate for seasonal flows, this project will allow Sterling Ranch to access deep underground water during dry conditions. 

The district is also planning a regional rainwater harvesting project in partnership with state universities. If completed, it will be the first of its kind in Colorado and will allow the district to store rainwater for use in outdoor irrigation, according to district documents. 

In March, Dominion addressed the current drought conditions. Drought stages in Sterling Ranch begin once the provider cannot meet at least 90% of demands. 

“At this time Dominion’s physically available water supply exceeds 100% of our customer demands or normal conditions per our Dominion Drought Plan,” the statement said. 

Lone Tree

Lone Tree residents receive water from Denver Water, which is stored and distributed locally by Southgate Water & Sanitation District. SWDS operates 240 miles of pipelines, four storage reservoirs and pump stations to distribute the water that has been collected, treated and tested by Denver Water. Meanwhile, residents on the east side of Interstate 25 receive water through Parker Water & Sanitation District.

This structure allows smaller communities to access large, established surface water systems without duplicating costly treatment and delivery infrastructure.