The Dirty Dozen: Design, Construction, and Operational History of Deer Island's EggShaped Digesters

The Massachusetts Water Resources Authority (MWRA) Deer Island Treatment Plant's 12 eggshaped digesters may be the most striking architectural forms on the site, but their existence was by no means envisioned from the start. The early design plan for the 1270 MGD facility called for anaerobic digestion, but the road that led to the selection and commissioning of the eggs involved no small amount of trepidation and debate. The object of this presentation is to tell the story of Deer Island's eggs, starting with their first suggestion, touching on design and construction challenges, and finally relating some of the lessons and concepts learned through the short operational experience since the phased 1995–98 start-up of the facility.