
Neuse River Resource Recovery Facility Bioenergy Recovery Project
Raleigh, NC
Merit Award
Sent by: Crowder Construction Co.
Owner: Raleigh Water
Main design company: Hazen and Sawyer
General contractor: Crowder Construction Co.
Built into North Carolina’s largest wastewater treatment plant for the city of Raleigh, this $205.4 million project converts wastewater biosolids into renewable natural gas. It integrates thermal hydrolysis and anaerobic digestion, using high heat and pressure to increase biogas production, expand digester capacity and reduce biosolids volumes by 50%. The resulting biosolids meet EPA Class A standards for unrestricted reuse, while the biogas is upgraded to pipeline-grade renewable natural gas.
The team encountered poorly compacted soils and large underground blocks. Instead of installing deeper foundations, crews preloaded the soils with material from a nearby city-owned borrow area and crushed excavated blocks for the aggregate base.
Built within an active 75 million gallon per day wastewater treatment facility, the project required careful sequencing and coordination to maintain uninterrupted treatment operations throughout construction. Process tie-ups, shutdowns and transitions were planned with plant personnel to ensure continuous service and regulatory compliance.
The facility now supplies renewable natural gas to more than 70 GoRaleigh transit buses daily, making Raleigh the first municipality in North Carolina to power its transit fleet with gas produced from its own wastewater system. The project also reduces transportation and disposal needs while generating revenue from surplus gas sales.
