The sight of trucks bringing water up the mountain to the tiny village of Cloudcroft, N.M., has become familiar to its 900 or so local residents, many of whom are American Indians. Despite its small groundwater supply system, the town can grow to 3,000 people during peak tourist season.
The limited groundwater supplies and virtually non-existent sources of surface water are insufficient to provide enough water to the village, so the residents have relied on trucked-in water during those times of the year when the population swells.
"That's not what we would call sustainable," says Jeff Mosher, executive director of the National Water Research Institute, Fountain Valley, Calif. "They, literally, are running out of water."
Mosher is working with a team of consultants and the New Mexico Dept. of Environmental Quality to plan and oversee the construction of a water treatment facility that will treat wastewater to a drinkable standard. Begun in 2006, the project ran into difficulties with preliminary designs and a lawsuit that alleged faulty construction, which held up progress for years.
The project is small, relatively speaking. Currently under construction with a new team, the new treatment system will bring 100,000 gallons a day of purified water to local residents when complete sometime in 2016.
Although Cloudcroft is an extreme example, it is not unique. As droughts caused by climate change spread—and are expected to grow significantly—throughout the parched Southwest, utilities increasingly are looking at all options to diversify their water-supply portfolios, and those options include direct and indirect potable reuse.
Although water recycling has been used for decades for irrigation and industrial applications, treating wastewater to a safe drinking level, either through additional treatment—that is, direct potable reuse (DPR)—or through an environmental or engineered buffer, such as a reservoir—that is, indirect potable reuse (IPR)—has been less common. However, it is growing as a viable option for many utilities.
"I think the droughts of the past couple of years will only stimulate the communities in very arid climates to consider potable reuse," says Julie Labonte, senior vice president at MWH Global.
Numerous municipalities and utilities in California, including the Santa Clara Water District, near San Francisco, and the city of Los Angeles, as well as those in Arizona; El Paso, Texas; Florida; and even Oklahoma are looking seriously at adding potable-reuse projects into their programs over the next few years and decades.
One of the largest is San Diego's PURE water program, a conservation and recycling program with a significant IPR component, currently in the preliminary design stage. The city has already built a 1-million- gallon-a-day (mgd) pilot advanced water purification facility to demonstrate to the public and public officials the feasibility and safety of the technology used.
MWH Global is program manager, along with Brown and Caldwell and Trussell Technologies. The team is providing program, risk and change management, preliminary design services of up to 10% on all facilities involved with the project's first phase, and some design work of up to 30%, also for the first phase.
Labonte, who is also the lead on the PURE water program management team for MWH, says the first phase of the program involves building an advanced water purification facility to produce 30 mgd of purified water. The city will select a final design team sometime in 2016, and construction will begin in 2019.
