A tunnel that will help prevent sewer overflows into the Connecticut River is in the early stages of construction. The tunnel will be approximately four miles long, 18 feet in diameter and 200 feet deep underground that will carry storm water and sewer overflows to the Hartford sewage facility and help keep untreated water out of the Connecticut River. The Connecticut River is the longest river in the New England region of the United States. Flowing roughly southward for 406.12 miles through four U.S. states. The $500 million South Hartford Conveyance and Storage Tunnel will run from West Hartford to the Hartford Water Pollution Control Facility and is a key piece of The Metropolitan District’s 20-year Clean Water Project that aims to safeguard the future of the Connecticut River by cleaning up discharges to streams and reducing oxygen-depleting nitrogen in the river, which ultimately flows to Long Island Sound.
The tunnel-boring machine will start at the Hartford treatment plant and cut slightly uphill to allow gravity to move the wastewater to the plant. The tunnel will end in a private West Hartford industrial area off Talcott Road, between Quaker Lane and New Park Avenue. The massive tunnel will collect the combined sewer overflows from south Hartford and sanitary sewage overflows from West Hartford and Newington. The additional capacity and more controlled tunnel inflow will prevent the plant from being overwhelmed, as well as, diversion of untreated overflows into the river during heavy rain. The project is being paid for largely with revenue bonds, plus low-interest state loans and grants. A “Special Sewer Service Charge,” now at $2.90 per 748 gallons of water used for customers, is generating revenue to help repay the bonds and loans. The special charge took effect several years ago. The charge is in addition to the current water charge of $2.53 per 748 gallons.