BOSTON — Sewage plant operators must give more timely public notice of spills into rivers and other waterways under proposed state regulations.
The draft rules rolled out by the state Department of Environmental Protection on Monday, which stem from a law signed in February by Gov. Charlie Baker, would will require operators to tell the public and local boards of health within two hours of a combined sewer overflow spill.
Operators would also be required to post signs or other notices near and around the outfalls notifying the public of the potential health hazards.
State environmental officials say the proposed rules, which would go into effect next year, will improve public awareness of sewage spills into the state’s waterways.
“We tried to develop these rules taking into account the letter and the spirit of the legislation,” MassDEP Commissioner Martin Suuberg said. “And we tried to make sure we were thoughtful about the regulations by talking to people who use the rivers, public health officials and importantly the wastewater system operators.”
The current rules require sewage systems to notify MassDEP no later than 24 hours after a discharge, but observers say those requirements are inadequate.
The only catch is that communities won’t know exactly how much sewage has been discharged.
Under the proposed rules, sewage treatment plant operators won’t be required to disclose that information as part of the initial notice of a CSO discharge.
“That means that when they send out the notification we won’t know whether it’s 2,000 gallons or 2 million gallons of sewage being discharged,” said John Macone, policy and education coordinator Merrimack River Watershed Council, which monitors CSO discharges along the river.
Lawmakers have filed a proposal aimed at closing that regulatory loophole by requiring testing of rivers and other waterways immediately following discharges. The bill, filed by Rep. Tram Nguyen, D-Andover, would also require sewer plant operators that report high bacteria levels around CSOs to develop a mitigation plan.
MassDEP officials point out there are requirements for treatment plants to provide estimates of discharges based on the past three years of data from previous spills.
They also note that they couldn’t go beyond the scope of the law, which didn’t call for disclosure of the size of CSO discharges.
While rules would apply to all of the state’s waterways, the effort was spurred by discharges into the Merrimack River, one of the state’s most polluted waterways.
Last year, the five sewage systems along the 117-mile river discharged an estimated 350 million gallons of raw or partially treated sewage, according to state data.
The effluent comes from overflow pipes built into decades-old sewer and storm-water systems, which were designed to spill when those systems become inundated.
Environmentalists say the overflows pose health risks to those who use the river for recreation, as well as the communities that draw drinking water from it. An estimated 600,000 people get their drinking water from the Merrimack.
Untreated sewage carries pathogens such as fecal coliform and bacteria that can cause dysentery, hepatitis and other diseases.
Under the proposed rules, plant operators would be required to post signage after a discharge: “WARNING! AVOID CONTACT WITH WATER – MAY CAUSE ILLNESS.”
Sewage plant operators along Merrimack and other major rivers have improved public notices amid outrage over discharges and heightened scrutiny from regulators.
A trade group that represents sewage treatment plant operators said the proposed notification rules could be costly for some smaller communities.
“Some larger cities have been monitoring CSOs for years, so they’ve already got the infrastructure,” said Mickey Nowak, executive director of the Massachusetts Water Environment Association. “But it could become a big expense for smaller communities that don’t have the staff or equipment to monitor the overflows.”
MassDEP plans to hold an online public hearing on the proposed regulations on Oct. 27.
Christian M. Wade covers the Massachusetts Statehouse for North of Boston Media Group’s newspapers and websites. Email him at firstname.lastname@example.org.