Heavy rain causes release of more sewage into Merrimack River

By: Allison Corneau 

It happened again.

Heavy rains last weekend caused sewage to discharge into the Merrimack River, with treatment plants in Haverhill and Greater Lawrence reporting releases.

The incidents are the latest in a series of such discharges. The problem has caused federal officials to order communities with old sewer pipe systems to make repairs — at a cost of tens of millions of dollars.

The discharges also have state officials and communities along the river creating a system to notify the public quickly when a sewage discharge happens. The system is designed to warn people who use the river — boaters, kayakers, even swimmers and people whose dogs go into the waterway — to stay away from the Merrimack for a period of time after a discharge.

The discharges happen when heavy rains run into pipes carrying both storm water and sewage, resulting in too much fluid for the system to handle. Such systems are known as Combined Sewage Overflow systems, or CSOs.

In the incidents last weekend, eight out of 13 sewage outfall pipes in Haverhill were activated for 25 minutes starting at 4 p.m. on Sunday, according to the Merrimack River Watershed Council. In the Greater Lawrence Sanitary District, three out of five outfall pipes were activated from 4:07 p.m. until 5 p.m. Sunday. An unknown amount of sewage was released into the river in those two events, the watershed council said.

Health officials recommend that people avoid direct contact with river water for 48 hours after a sewage discharge, the watershed council said.

State Sen. Diana DiZoglio of Methuen who also represents Haverhill is among the local leaders calling on the federal government to create "sustainable solutions" to clean up the river.

"Legislative action on the numerous bills that would provide CSO (combined sewage overflow) notification and prevention are long overdue," DiZoglio said. "While the pandemic has interrupted a lot of the work being done locally to help clean up the Merrimack River, there is still so much that could be done in the legislature that has been unnecessarily stalled. We need to take action yesterday."

Congresswoman Lori Trahan, who represents much of the Merrimack Valley, has proposed legislation that would provide billions of dollars in grants to communities to modernize their storm water systems. The improvements would prevent the overflow of storm water mixed with raw sewage into rivers, lakes and, in the case of coastal communities, the ocean.

In 2019, Trahan proposed the Stop Sewage Overflow Act, which would increase money for the Environmental Protection Agency’s grant program for communities to address CSOs.