Skip Links

Covanta SEMASS

SEMASS Facility Photo

Covanta SEMASS

Covanta’s Southeastern Massachusetts (SEMASS) Resource Recovery Facility provides the community with an alternative to municipal solid waste (MSW) disposal at landfills. Since opening in 1988, the 95-acre facility in Rochester, MA, has employed a shred-and-burn technology to create fuel, enabling the plant's processing of more than one million tons of solid waste each year. This is more than one-fifth of all MSW generated in Massachusetts annually. The resulting electricity serves nearly 40 communities in Southeastern Massachusetts, Cape Cod, and the metropolitan Boston vicinity, and meets the needs of more than 75,000 homes. The facility also recovers nearly 35,000 tons of recyclable ferrous and non-ferrous metals annually from pre-combustion magnets and bottom ash processing. 

Commercial Operation:


Waste Processing Capacity:

3,000 tons per day of processed refuse fuel

Air Pollution Control Equipment:

Dry scrubbers for acid gas control, carbon injection for mercury control, and electrostatic precipitators and baghouses for particulate control.

Energy-from-Waste System:

Three Riley-Stoker boilers each with 375 million British thermal units (MBtu) per hour design heat release rate 

Energy Generation:

300,000 pounds per hour @ 650 pounds per square inch absolute (psia)/750°F

Awards and Recognition:

  • American Academy of Environmental Engineers' Ash Technology Honor Award
  • American Society of Mechanical Engineer's (ASME) Solid Waste Processing Facility "Honorable Mention" Recognition Award (2007) 

Community Initiatives

Mistic Aquarium


Mystic Aquarium

Covanta SEMASS recently teamed up with Mystic Aquarium and our SECONN, Haverhill, and Bristol facilities to create an interactive exhibit showcasing how discarded marine debris can be turned into clean energy. This exhibit, entitled “Covanta Cove,” includes a water feature depicting a local pond, a diorama reflective of a local CT neighborhood, a scale-model of a typical Energy-from-Waste facility, and two giant, mobile claws. Visitors can maneuver the cranes to collect debris from the cove’s pond, and then deposit the “waste” into receptacles for processing at the facility. It’s a great way for people to experience the EfW process first hand.

Ton of Thanks

Covanta SEMASS honored the Cape Cod Cooperative Extension’s (CCCE) Hazardous Materials Program with its “Ton of Thanks” award for its exceptional leadership in mercury education and awareness. This award is part of Covanta’s celebration of removing over one ton of mercury from the waste stream through events and public awareness. With the help of CCCE, Covanta SEMASS has collected over 1,800 pounds of mercury thermostats and other items since 2004. 


Covanta SEMASS

141 Cranberry Highway

West Wareham, MA  02576



Mark Davis


Visit Our Facility!

If you would like an escorted tour of our facility, please reach out. We welcome the opportunity to show you how our resource recovery process works.

Click here for tour checklist (PDF)

All tours must be scheduled in advance. Please contact Patti Howard, Community Outreach Manager, at 508-291-4427 or email

To search for careers in this area click below: