News | November 12, 2015

The City Of Gresham Honored With Project Of The Year Award

The American Public Works Association’s Oregon Chapter has recently selected the City of Gresham as winner of the Public Works Project of the Year Award in the Environmental category (including Water, Wastewater, and Stormwater). The Gresham Wastewater Treatment Plant (WWTP) was recognized for its Cogeneration (Cogen) Expansion Project – which allowed the plant to go energy net zero. Carollo Engineers served as the primary consultant on the project.

With the completion of the Cogen Expansion Project, the Gresham WWTP has achieved its seven year old goal of becoming energy net zero. Using the biogas byproduct from anaerobic digesters to fuel cogeneration engines, the plant now generates more electricity than it uses on an annual basis and has turned the City’s biggest energy user into its leading energy producer.

“We are pleased that the City of Gresham was honored with this prestigious award from the American Public Works Association,” Jeff McCormick, Associate Vice President and Principal Engineer, Carollo Engineers. “We believe that the Gresham WWTP is a shining example of a new way to look at wastewater treatment, and it’s blazing a trail to be emulated nation-wide. It’s not just about treating waste, it’s about recovering resources – in this case, generating renewable energy worth over $500,000 annually.”

As the Pacific Northwest’s first energy net zero WWTP and one of only a few in the United States, the Gresham WTTP is gaining national and international attention – helping to promote the use of this reproducible technology. It is estimated that only eight percent of WWTPs in the U.S. with anaerobic digestion generate electricity or hot water as a renewable energy resource.

With the completion of the Cogen Expansion Project, all months since February 2015 have been energy net zero months. With the expansion, a second 400 kW CAT cogen unit was installed which enabled the WWTP to generate all the energy needed to operate the plant. The WWTP’s first energy net zero day was February 12, 2015 and trends indicate that 2015, and all future years, will be energy net zero for the plant.

The expansion also provides a boost to the community. By adopting this technology and becoming more energy efficient, the City is saving approximately $500,00 per year on electricity. The project will also help the City to meet two key goals of its sustainability policy implemented in 2009: to have an 80 percent reduction in City greenhouse gas emission by 2050, and to use 100 percent renewable energy for City facilities by 2030.

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.

Source: Carollo Engineers