BARRIER BEACH COMMUNITY OPTS FOR VACUUM SEWERS

This paper presents the selection and development of a vacuum wastewater collection system to serve Plum Island, Massachusetts. Plum Island is a barrier beach community with a seasonal population of approximately 4,400. Residents currently rely subsurface wastewater disposal systems, many of which are failing and contaminate nearby shallow drinking water wells. The Massachusetts Department of Environmental Protection issued a consent order to the community, requiring the design and construction of a water distribution and wastewater collection system. Conventional gravity, low pressure, and vacuum systems were analyzed to determine the most appropriate collection system for the island. Vacuum sewers were recommended based on cost savings and other factors that are summarized in this paper. The system design includes shallow, small diameter pipes that follow the topography, minimizing the potential for costly and difficult construction due to the island's high groundwater and narrow streets. The vacuum system also includes one central vacuum pumping station that maintains vacuum pressure throughout the pipe network.