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Construction begins on City of Longmont project to convert sewage treatment gas to renewable fuel

Driven by an age where sustainable resources are increasingly important, the City of Longmont has begun construction on its Biogas Treatment and Renewable Natural Gas (RNG) Fueling Station Project. Once complete, this innovative project will transform sewage gas from the wastewater-treatment process into sustainable fuel for the City's trash trucks.
city of longmont logo
city of longmont logo

This content was originally published by the Longmont Observer and is licensed under a Creative Commons license.

Driven by an age where sustainable resources are increasingly important, the City of Longmont has begun construction on its Biogas Treatment and Renewable Natural Gas (RNG) Fueling Station Project. Once complete, this innovative project will transform sewage gas from the wastewater-treatment process into sustainable fuel for the city's trash trucks.

The city will replace 11 of its diesel trash trucks with trucks capable of using RNG fuel. It is estimated that the city will offset over 100,000 gallons of diesel fuel annually, reducing greenhouse gas emissions by about 1,000 metric tons of carbon dioxide equivalents per year — the equivalent of removing 200 cars from the road. In addition, by building the RNG Fueling Station, the city is also able to take advantage of valuable credits from the United States Environmental Protection Agency’s Renewable Fuel Standard program.

“This project is directly in line with the city’s Sustainability Plan,” says John Gage, Civil Engineer and project manager for the City of Longmont. “In 2018, Longmont completed the city’s first greenhouse gas inventory to develop a baseline of greenhouse gas emissions. Based on the results, we prioritized a number of strategies to reduce citywide greenhouse gas emissions, such as the transition to RNG trash trucks.”

The city has contracted with Carollo Engineers, a top national design firm with local offices in Broomfield and Littleton, and CGRS, a Fort Collins-based environmental services and construction company, to design and construct the project. CGRS is serving as project manager and construction contractor for the project as well as designing the new fueling station; Carollo designed the biogas treatment system.

“I thought we were uniquely qualified with our experience in designing and building both wastewater and RNG facilities,” says Randy Kenyon, CGRS Senior Engineer and project manager. “We have a great team collaborating with the City of Longmont to bring this important project to fruition.”

CGRS’s CNG Construction Services department is building the entire project, which consists of two sites: the first is the city’s current wastewater plant to which CGRS will provide interconnections and gas treatment equipment to clean the sewage gas. The RNG pipeline will run from the wastewater plant, 501 1st Avenue, to a second site on the northwest corner of the property off of South Martin Street. CGRS will build a 17,000-square-foot building with four bays for indoor fueling of the city’s trash fleet and a two-story, 5,000-square-foot administration building on that site.

Becky Luna, PE, Design Manager for Carollo, says her company is excited to support the city's sustainability initiatives as well. “This state-of-the-art project is sustainability in action – the city will be able to make use of an untapped resource, reduce greenhouse gases and save on fuel costs,” she says. “Longmont will be the first city on the Front Range to implement a renewable vehicle fuel project; other utilities have been looking at Longmont as a model for their operations.”

Learn more about the project.

See regular updates about CGRS’s progress on the City of Longmont’s RNG Project here.