State lawmakers who say their hands are tied on the dumping of untreated wastewater into the Connecticut River because much of the material comes from Massachusetts are seeking help from federal regulators to force the commonwealth to minimize its raw sewage discharges.
Three Massachusetts facilities that are permitted to conduct so-called combined sewer overflows, or CSOs, discharged a total of 511 million gallons of untreated material into the Connecticut River last year, according to the Massachusetts Department of Environmental Protection.
CSOs from Connecticut facilities discharged a total of 277 million gallons of material last year…