BOSTON (WBZ NewsRadio) — Boston is a historic city, right down to its sewer system. The area uses something called Combined Sewer Overflows (CSOs) — an invention that cropped up in the late 19th century. Those sewers were cutting edge around the turn of the century, but they're now starting to show their age.
Combined Sewer Overflows are called "combined" because they let waste water and storm water flow into basically the same pipes. On a dry day, this poses no problems. But when storms dump torrential rain on the area like they did this past summer, the system is designed to spill some of that combined slurry of sewage and rain out into nearby rivers and streams. Without that vital pressure valve, enough rain would send everything shooting back up the pipes and into our homes. These days, much of Greater Boston's sewers are run by one system: the Massachusetts Water Resources Authority, or MWRA.
'Built for an Earlier Time'
A hundred years ago, CSOs were a boon for public health. Chamber pots were no longer being emptied onto the streets, and waste was efficiently carried away from where people lived and worked. But in modern society, the system is becoming outdated.
At a public meeting last week, Katherine Lange with the Massachusetts Rivers Alliance said the CSOs in this area are systems “that were built for an earlier time and are unequipped to meet the demands of today.”
For one, we have more people roaming the streets than before. City planners estimate Boston will easily top 700,000 people by 2030, within striking distance of records set in the 1950s before suburbanization. Modern-day pollutants are also not what they used to be. Streets once traversed by horses and buggies are now filled with cars. There’s now anti-freeze on top of animal waste. Dumping polluted runoff and sewage into local rivers is causing serious concern among local environmental groups, like the Massachusetts Rivers Alliance.
The situation will almost certainly get worse as our climate changes. We are already getting more precipitation than before. Current climatology suggests that the rain will only pound down on New England harder as the earth heats up. That means a furious barrage of storms that the architects of our sewers couldn't have had in mind when they laid the groundwork of our water systems. The more rain brought on by climate change, the more sewage overflows.
“Our water infrastructure was not built for these new trends that we are experiencing,” Lange said in the meeting.
The summer of 2023 was a particularly wet one with heavy rains and catastrophic flooding, like in Leominster. The rain, and the overflows it causes, can have a negative impact on public health. Contact with water after a sewer overflow can cause serious illness.
“This has been a terrible year,” said John Macone, with the Merrimack River Watershed Council. “We have had three times as much sewage going into the [Merrimack River] as normal. And we have 700,000 people who drink out of this river.”
Macone made the comments at a hearing of the Joint Committee on Environment and Natural Resources on Beacon Hill Wednesday afternoon. State lawmakers heard testimony on a number of bills relating to hazardous waste, septics, sewers, and toxic management.
"CSOs carry pathogens, the bacteria, the viruses. And what research is showing is that if you live in an area that has CSOs, and this has happened in the Merrimack in particular, you see this correlation between high intensity rainfall and trips to the emergency room for gastrointestinal illnesses," Patrick Herron, executive director of the Mystic River Watershed Association, said at the hearing.
Concerns were also raised about recreation. A crowd of thousands came out for the Head of the Charles over the weekend. But, Emily Norton with the Charles River Watershed Association said there was a red flag day during the annual event, meaning it was potentially dangerous to be out on the water.
“It’s simply unacceptable,” Norton said.
Digging a Way Out
The problems with CSOs are well documented. So how does Massachusetts dig its way out of a sticky sewer bind?
One proposed bill, An Act relative to combined sewer overflows (H.886), aims to do away with most untreated CSOs for the millions of people on the MWRA service area by 2035. But, updating our sewers — like separating wastewater and storm pipes, for example — would be incredibly expensive. In a 2019 report on the Charles River, the MWRA estimated it would cost $18.6 billion to completely eliminate CSO discharges.
State Rep. David Rogers is one of the bill's sponsors. In a statement to WBZ NewsRadio, Rogers acknowledged that sewer separation would be costly but said funding could come from multiple different places. That could include the MWRA, affected municipalities, and the federal government.
"While this will not be cheap, we cannot use this is an excuse to allow this level of pollution to continue unabated," Rogers said.
Norton said it is important push for these updates and get funding now that the federal Bipartisan Infrastructure Law is on the books. "Now really is the time to make the case, get organized, get in line for these projects, and beat out other areas of the country," she said.
For its part, the MWRA said it has already spent more than $900 million dollars to address CSOs, "an effort that has resulted in the reduction of almost 90% of overflows" in its service area. "We continue to work to find ways to address these environmental issues," a MWRA spokesperson said. The authority declined to comment on the proposed legislation.
Sewer separation isn't the only option. At the hearing, Norton said other cities were trying different things, like storing stormwater in rain gardens and storage tanks until it can be treated. "And maybe that would even be cheaper," she said.
WBZ NewsRadio's Chaiel Schaffel (@CSchaffelWBZ) reports: