Over the summer, in 2022, Somerville, Cambridge, and Massachusetts Water Resources Authority held their first Alewife CSO Control Plan public meeting. At this meeting, Cambridge resident Ann McDonald asked, “When will the Alewife Brook not smell?” Save the Alewife Brook’s David Stoff has been asking this question since the 1990’s.
When you take a walk along the Alewife Greenway Path, the first thing you are likely to notice is the stench. What you are smelling is disgusting sewage vapor escaping from the area’s terribly old sewer system! Last year, that old sewer infrastructure was responsible for dumping 51 million gallons of untreated sewage into Alewife Brook.
On our recent tour of the MWRA’s Alewife sewer system, David Stoff asked MWRA’s Stephen Cullen about odor control on the Alewife Greenway, specifically at the Alewife Brook Sewer siphon near Bicentennial Park. As a result of Save the Alewife Brook’s inquiry, the MWRA sealed the siphon access with clear caulking. This solution worked! And it could be duplicated for all such sewer infrastructure along our popular public path.

The MWRA’s Alewife Brook siphon structure, near Bicentennial Park in Arlington. Photos by David Stoff.

A silicon seal on the MWRA’s sewer system keeps sewer vapors from escaping from the old sewer system.
The nauseating odor leaking from the sewer system causes a gag reflex, ruining many nice walks and picnics in our park. That odor dramatically diminishes the quality of life for everyone who lives near, walks, or rides a bike along the brook or over the Mass Ave bridge to and from Cambridge. It affects a lot of people!
A Few Words About Sewer Odor from Technical Advisor David White:
There are three primary sources of the bad odor along Alewife Brook:
(1) leaks from the manholes of the sanitary sewer lines that run next to the brook
(2) leaks from some of the Combined Sewer Outfalls which are open to the air
(3) from CSO sewage discharges
The manhole problem can easily be fixed, although the sewer gas has to come out somewhere. The CSO sewer vapor problem is a little more complicated but doable. The CSO sewage discharges need to be reduced, treated, and eliminated.
Afterall, on our summer tour of the MWRA’s sewer system, MWRA kindly treated our group to sandwiches, potato chips, and soda at the Deer Island Wastewater Treatment facility, where there was no foul smell at all.
Why is there no smell at Deer Island? In response to public pressure, MWRA installed a sophisticated and modern odor control system at Deer Island. And, according to MWRA, a well-managed sewer system does not smell.