With nearly all seven states within the 250,000-sq-mile Colorado River basin scrambling to conserve their apportionments from the river system’s increasingly depleted resources, interest in securing alternative local drinking water supplies is soaring.

The reliability of water supplies in the arid and semi-arid Mountain States is a growing concern for the public and the engineering community in the wake of persistent drought and a multiyear downward trend in Colorado River flow and storage. Robust snowpack in early 2023 brought a welcome reprieve, but one good year cannot overcome decades of drought.

Water recycling and other forms of reuse—such as direct potable reuse—have become mainstream enough to attract the attention of the U.S. Environmental Protection Agency.