Carollo Engineers' Delano biottta® Project Wins ACEC Award

The American Council of Engineering Companies recently announced their 2016 Engineering Excellence Awards, selecting Carollo Engineers as an Honor Award winner for the Delano biottta™ Wellhead Nitrate Treatment Demonstration Project.

In April of 2014, California approved a grant-funded project to help provide the City of Delano with safe drinking water. The $5M grant allows the City to remove one of California’s most widespread groundwater contaminants: nitrates. It funded a three-year pilot and demonstration project for the removal of nitrate from drinking water, and Delano subsequently installed and began operating a biottta (biologically-tailored, two-stage treatment approach) nitrate system in the Fall of 2015. This system, designed by Carollo Engineers, is used on critical municipal supply well 35, that produces water exceeding the required safety levels for nitrates.

The City has sufficient water supply to meet demands, but the supply well requiring treatment was needed to ensure future supply. Carollo’s patented biottta process uses naturally-occurring bacteria to treat a range of groundwater contaminants, while eliminating traditional, environmentally harmful waste streams, increasing water recovery rates, and reducing treatment costs. The City needed a nitrate treatment system that doesn’t produce a nitrate-laden concentrated waste stream, requires limited operator attention, and is cost-effective.

“Our process will help make sure that the well is an integral part of Delano’s future potable water supply,” said Chris Cleveland, VP, senior project manager at Carollo Engineers. “The system is a cost-effective, sustainable solution for removing nitrate from groundwater, resulting in lower waste disposal costs than other treatment options. The system is low-energy, cost-effective, and flexible, and we think it makes an ideal fit for Delano.”

Responding to these needs, the extended pilot study showed that the biottta treatment system efficiently degrades nitrate to harmless nitrogen gas, avoiding the generation of a concentrated waste stream. The pilot also demonstrated the automated nature of the treatment system, which limits manual operation demands. Finally, piloting confirmed the anticipated design and operating criteria,ensuring a cost-effective solution for the City.The system also removes nitrate from groundwater without producing a concentrated waste stream. As a result, the City’s future O&M costs will be economical, compared to conventional phase separation technologies that produce a brine waste.

The three-year project consisted of a ten-month pilot study, and it will provide twelve months of actual full-scale operational data to refine and confirm the long-term economic benefits that can be realized by the City and other communities in similar situations. With the process in place, the City has a treatment facility that ensures that Well 35 is an integral part of its water supply.

About Carollo Engineers
For more than 80 years, Carollo Engineers has provided a full range of innovative planning, design and construction management services to meet the water and wastewater needs of municipalities, public agencies, private developers and industrial firms. For more information, visit www.carollo.com.