New Sound Dampening System at Ashmont

Having realized that the two automatic greasers on the trolley loop at Ashmont are almost useless at getting grease spread throughout the loop and reducing the screech from cars going through the loop, the T installed last weekend an even more advanced system for lubricating the rails.

They installed an automatic sprinkler system around the loop.

For about $20 worth of materials from Home Depot, they could've just had an inspector grease the loop by hand every morning. Instead they wasted a couple thousand $$ on this nonsense, plus whatever the added water bill is going to be.

Toronto uses this in a station in a tunnel. I was thinking of this being a solution here, but then our climate made that idea not really a good one.

Why didn't they build a wider loop when they rebuilt it?

Toronto uses this in a station in a tunnel. I was thinking of this being a solution here, but then our climate made that idea not really a good one.

TTC also uses water as a lubricant in a couple other places... McCaul Loop downtown is one that immediately comes to mind. I assume they just don't use the water in winter months.

I seem to recall a distant memory of sprinklers being used on that tight-ish curve where the Ashmont Branch of the Red Line diverges from the Braintree/Old Colony right of way. Do they still do that?

I think they still do, Jon, about a year ago, when i was riding Ashmont Red line, they still had the sprinklers at the splitoff where the Commuter and Braintree Extensions are. Also, they should put that same sprinkler water type at the tight turn (both directions) at the south end of Harvard Station

Sprinklers were also used in the past neat Orient Heights/ Wood Island, but only on hot summer days. I was told it was to keep heat kinks out of the rail more than to keep the noise down.

Should reinstall resilient wheels on the PCCs as well.

Boston Globe - July 7, 2010

Trolley turnaround tests nerves
Neighbors say the noise tops 100 decibels at Ashmont Station

By Eric Moskowitz, Globe Staff | July 7, 2010

At its best, the noise emitted by the MBTA’s Mattapan Trolley as it turns at Ashmont sounds like the long, low moan of a whale. At its worst, it is like nails on a chalkboard coupled with a piercing whistle, drawn out for half a minute.

Using noise meters from RadioShack, neighbors have measured the sound in excess of 110 decibels at the platform (louder than a jackhammer) and at 100 decibels in the kitchens of the Victorians, colonials, and three-deckers surrounding the station, with the windows open. The noise repeats every five to 12 minutes for 20 hours, from the first trolley at 5 a.m. to the last at 1 a.m.

“It’s like a toothache,’’ said Kim Pengelly, 49, a caterer who owns a condo on nearby Beale Street. “It doesn’t go away. . . . It cuts through everything.’’

The shrieks and screeches, which the MBTA says it has temporarily fixed, are an unexpected byproduct of the MBTA’s roughly $50 million investment over the last five years to rebuild Ashmont Station and to refurbish the historic trolley line that runs between Mattapan and the Ashmont section of Dorchester.

The line uses a fleet of 10 painstakingly restored trolleys from the 1940s. The trolleys are beloved by transit aficionados, who visit Boston to ride them, as well as by local residents who over the years have called on the T to preserve them.

But the trolleys lack the modern ability to go in reverse. As a result, the rebuilt terminus at Ashmont includes an elevated loop for the trolleys to change direction, albeit with a curve so tight the friction of the steel wheels against the steel track causes a screech. Residents say they have been tortured by the sound since that loop opened in December 2007.

“It’s not to be confused with normal train noise,’’ said Moo Bishop, a Bushnell Street resident who has organized neighbors on the issue. “I live next to the train. I’ve always had train noise, I expect train noise, I’m not complaining about train noise. This is something that’s just at a sound level that is unbearable.’’

Over two years, T officials made several attempts to quiet the screeching while telling residents they were making progress, telling them the problem was not as bad as they thought and telling them they had simply forgotten what the trolleys used to sound like before construction, several neighbors said.

The screech is exacerbated in warm weather. As this summer approached, Bishop formed a Facebook group with her neighbors and they began pressing the T to resolve the problem.

With help from local elected officials, the neighbors arranged a meeting last month with the T’s new general manager, Richard A. Davey. About a week later, the T installed what officials and residents call a semisuccessful solution: $30,000 in special blankets draped on fences surrounding the tracks, and thousands of gallons of water sprayed along the route by a network of hoses and sprinklers.

The water reduces the friction that causes the squealing, while the blankets dampen the noise. Neighbors say the noise level is now acceptable, but they worry about what will happen when winter comes; they also say there have been scattered moments when the screeching still pierces the neighborhood.

Mary MacMasters, a lifelong Bushnell Street resident, said the “ear-splitting’’ sounds have been replaced by the constant rush of water sprinkling the tracks and draining to the neighborhood below.

“That’s their solution? I do everything I can: I recycle, I conserve, when I brush my teeth I don’t run the water,’’ said MacMasters, 55, who called the T a good neighbor for most of the six decades her family has owned the house. “Now I hear that going on for days?’’

T officials acknowledge the blankets and water are temporary measures and say they are seeking a long-term solution short of reconstructing the loop or disrupting trolley service.

“The T wants to be a good neighbor, and we’re going to solve this problem,’’ Davey said yesterday.

The 2.55-mile Mattapan High-Speed Trolley Line, reputed to be the only line in the country that runs through a cemetery, carries 4,700 one-way riders a day, a fraction of 1 percent of the MBTA’s daily riders. On paper, it appears to be an eight-stop extension of the Red Line route beyond Ashmont. In reality, the trolleys are operated and maintained by Green Line workers, and the vehicles were painted green until a few years ago.

Since the service resumed, following construction and 18 months of busing, the trolleys have been painted pumpkin orange and bedecked with old-fashioned insignia not used anywhere else in the MBTA system. Riding the trolley is like stepping back in time, save for the recently added air conditioning and the posters carrying Davey’s face and the message “We’re only as good as our last rush hour.’’

Under a 99-degree sun yesterday, MBTA officials stood on the Ashmont trolley platform as dozens of sprinklers watered the bend along both sides of the track. They pointed out the features that have not worked — a pair of solar-powered, grease-pumping “friction modification systems’’ — as well as the sprinklers and blankets. New signs have also been effective, encouraging trolley operators to proceed more slowly around the bend, at 3 miles per hour.

An audio specialist is working with the T to identify more precisely the extent of the problem and its cause, including which trolley components are causing the worst noise at different points in the bend.

“We’re really not sure exactly what the fix for this is going to be,’’ said Brian Dwyer, the T’s director of light rail operations. “This is buying us time for us . . . to investigate what we think the best fix will be.’’

Eric Moskowitz can be reached at [email protected].

I saw a huge spike in views for a video I put on YouTube of a PCC rounding the loop and I discovered it had been linked to by a blog reporting on the issue. I took the video back in 08 partly because I wanted to capture how loud the loop was. I guess I wasn't the only one.

The new water system sure puts the "damp" in sound dampening system.

Would this be a flange greaser problem?

In europe they have been combatting this noise by putting weights on rubber on side of rail.
it dampens the resonance of the railweb with great succes.

Three seconds with an internet search uncovered one possible solution:

http://pennmach.com/Transit/ResilientWheels.asp

just about every trolley already uses these wheels, its the rail that sqeels.

Just about... but not the Mattapan PCCs. They use solid steel wheels.