In a Flash: Blinking Yellow Signals Lead to Drop in Accidents at Lenox Intersection

June 18, 2016

LENOX >> For years, making a southbound left turn onto Holmes Road from Routes 7 and 20, known locally as Pittsfield Road, was a potential nightmare for motorists.

Following a deadly crash in the fall of 2012 and a total of 17 other collisions going back to early 2009, the state Department of Transportation received a report from Lenox Police Chief Stephen O’Brien detailing the incidents. The worst involved four vehicles on Oct. 4, 2012, resulting in one death and a severe injury.

State Rep. William “Smitty” Pignatelli, D-Lenox, former MassDOT District 1 Director Peter Niles and Gregory Federspiel, the Lenox town manager at the time, urged swift action for a safety fix at the accident-prone intersection. Second only to Coltsville in Pittsfield as the busiest in Berkshire County, 27,000 vehicles pass it daily, on average year-round — many more in the summer.

Agreeing that the intersection was especially dangerous, MassDOT fast-tracked the installation in January 2013 of the first multiphased signal in Massachusetts specifically designed to help drivers safely navigate the left turn. The signal includes a flashing yellow left-turn arrow alerting southbound Pittsfield Road motorists in the left-turn lane onto Holmes Road to yield to oncoming traffic.

The result, O’Brien told The Eagle this week, has been a “drastic decrease” of 70 percent in the number of left-turn crashes at the site — only five since January 2013, with far fewer personal injuries.

“The impacts have been less severe,” he said.

As the result of the success in Lenox, similar flashing yellow arrows are now in place or planned at intersections from Cape Cod to the Berkshires, according to MassDOT’s State Traffic Engineer Neil Boudreau.

More than 350 traffic signals on state highways in at least 140 cities and towns are being converted. The $3,237,888 project that began last year is expected to be completed next summer.

Chief O’Brien welcomed the recent installation by MassDOT of flashing yellow systems in Lenox at the Route 7 and 7A intersection near the state highway department and at New Lenox Road.

In Pittsfield, there’s a newly upgraded flashing yellow traffic light for northbound traffic on South Street at South Mountain Road.

In all, 16 conversions have been finished in the Berkshires, according to Assistant State Traffic Engineer James Dinila, with one more to come: Three in Pittsfield, three in North Adams, four in Lenox, three in Lanesborough, two in Great Barrington, one in Lee and one in Great Barrington.

Because some drivers did not understand that “steady green circular indicators” allowing left turns but requiring them to yield to oncoming traffic, the department decided to replace these traditional “Protected-Permissive Left-Turn Phasing” (PPLT) signals with the “Flashing Yellow Arrow” systems approved by the Federal Highway Administration in 2009 after extensive testing in several states.

“Motorists see the flashing yellow arrow intuitively, it means proceed with caution if it’s safe to do so. The steady green gave them the notion that it’s OK to go,” Boudreau said. “We feel the yellow caution is a better indicator of what that left-turn movement should be.”

To be eligible for the upgrade, a state highway intersection must have a separate left-turn lane as well as an existing traditional turn signal, Boudreau said.

According to state Transportation Department statistics, about 25 percent of all crashes at traffic signals in Massachusetts are caused by left-turning vehicles against oncoming traffic. The agency points out that because of the angle of a collision’s impact, such accidents are more likely to result in injuries or fatalities.

Since three years of crash reports are required to determine the safety effects of the new signal system, Dinila said, the state has no complete data except for Lenox. But based on national studies, the upgraded signals result in a 25 percent reduction in fatal or serious crashes involving left turns, and a 20 percent drop in all left-turn accidents.

“Flashing yellow arrows are a proven highway safety measure,” Boudreau said.

Congested state highways with busy left-turn intersections such as Route 6 on Cape Cod are a major focus of the technological upgrade, he said.

Based on the national safety statistics, Boudreau said MassDOT decided on a systemwide fix.

“Instead of a Band-Aid approach, we decided to do it all rather than piecemeal,” he said.

He said towns and cities statewide are being encouraged to adopt the same technology on their local roads as the state highway system is using.

“Lenox was a test case because the police chief was fed up,” Boudreau said. “So we decided to try this, we put it up and it has been very successful. It’s a proactive rather than reactive approach to safety.”

Contact Clarence Fanto at 413-637-2551.

Upgraded traffic signals ...

The following Berkshire County intersections have MassDOT’s enhanced, four-phase flashing yellow arrow signals:

Great Barrington

Routes 7 & 23 (State Road) at Routes 7 & 183 (Stockbridge Road)

Route 7 & 183 at Monument Valley Road


Route 8 (Cheshire Road) at Berkshire Mall Road

Route 8 (Cheshire Road at Old State Road

Route 7 (S. Main Street) at Berkshire Mall Road


Route 102 (Pleasant St.) at Tyringham Road


Route 7 & 20 at Route 7A (Main Street)

Route 20 (Lee Road) at Route 7

Routes 7 & 20 at New Lenox Road

Routes 7 & 20 at Holmes Road

North Adams

Route 2 at Barbour Street

Route 2 at Airport Road

Route 8 at Walmart driveway


Route 9 (Dalton Avenue) at Meadowview Drive

Route 8 at Allendale Shopping Center driveway

Route 7 & 20 at Guardian Life/Pittsfield Country Club entrance (under contract)


Route 2 at Cole Avenue

Source: MassDOT Highway Division

How they work ...

Mass DOT is retrofitting several-hundred flashing yellow arrow signal systems across Massachusetts following a successful first in the state installation at Pittsfield and Holmes roads in Lenox. Here’s how they work for drivers seeking left turns at busy state highway intersections:

• Steady red arrow: Drivers turning left must stop.

• Steady yellow arrow. The traffic signal will be turning red. Drivers should not assume oncoming traffic has a red light, as their signal may still be green.

• Flashing yellow arrow. Left turns are allowed, but drivers must first yield to oncoming traffic and pedestrians, then proceed with caution.

• Steady green arrow. Drivers may turn left. Opposing traffic has a red light.

Source: Massachusetts Department of Transportation Highway Division