About the Sewer System

Wastewater from homes and businesses travels through miles of sewer lines to get to our Plum Island Wastewater Treatment Plant. The sewer system, or wastewater collection system, consists of 800 miles of sewer lines (including gravity pipe and pressurized force mains), more than 208 pump stations, and 12 miles of deep tunnels.

Our Wastewater Collection department operates and maintains the sewer system, which includes cleaning manholes, conducting smoke and dye testing to reduce infiltration and inflow, and other corrective and preventive maintenance.

Annual Wastewater Quality Report

Our 2017 report was published Oct. 2018. 

*The 2018 report, as well as each year following, will be published in February.


In 2009, our Wastewater Collection department received a National Environmental Achievement Award from the National Association of Clean Water Agencies for its Infiltration/Inflow Reduction Program. This project eliminated sources of rainwater in the sewer system, which takes up needed capacity and can cause sewer overflows during heavy rainfall.

Partnership for Clean Water

Our Plum Island Wastewater Treatment Plant became a charter member of this organization in early 2017. We proudly progressed to Phase II facility status on June 7, 2017. Our next step is to complete the comprehensive wastewater treatment facility self-assessment process, making the facility eligible to receive the Phase III Directors Award.

Video: Three Things to Know About Your Sewer Service