Town revisits roundabout for Blinker

By Aubrey Gibavic - May 18, 2006

After nearly a year of observing and collecting data from the notorious Blinker light intersection in Oak Bluffs, the Martha's Vineyard Commission (MVC) has produced a lengthy report detailing the possibilities for the future of the junction.

The report concludes that a roundabout, one of the five outlined possibilities, would produce the lowest accident rate, the least congestion and delays, and most improved air quality. This choice would also have the highest cost.

According to the report, construction costs would total between $400,000 and $450,000. MassHighway and the Federal Highway Administration are expected to furnish the construction costs.

Residents met with the MVC and Oak Bluffs selectmen last Monday at the Oak Bluffs Library to discuss the various options for the intersection of Edgartown-Vineyard Haven and Barnes roads.

Computerized diagrams, produced by the Martha's Vineyard Commission, show the details of two of the proposed plans for the problematic Blinker intersection in Oak Bluffs.

The selectmen requested the report after they scrapped an idea of building a roundabout at the intersection in 2004, to replace the four-way stop that was implemented a year earlier. The board rescinded their decision to build the roundabout after a public outcry citing multiple traffic impacts and bicycle and pedestrian safety.

The 28-page report, released late last month, provides detailed diagrams and accompanying explanations, comparing five possibilities for the intersection: the current geometry of the four-way stop; a four-way stop with a right turn lane; a traffic signal; a traffic signal with right turn lanes; and a roundabout.

The report highlights the pros and cons of a roundabout at the intersection, being careful to explain the difference from conventional rotaries. The report outlines that in a rotary, motorists enter a multi-lane circle at high speeds, and navigation requires "weaving movements." The roundabout, referred to as a "revolving door for vehicles," would have a single lane flowing around a 70-foot diameter landscaped circle. At the Blinker intersection, vehicles would slow to about 10 or 15 miles per hour while passing through.

The MVC produced the report after analyzing traffic patterns and levels of danger, in order to provide insight into a long-term solution for the intersection.

"The intersection ... is one of the most critical intersections on Martha's Vineyard," the report states. "It has been the subject of considerable discussion in recent years as to what is the best long-term solution for providing safe, efficient movement of vehicular, bicycle and pedestrian traffic at this central crossroads."

The report refers to the one existing roundabout on Cape Cod, on Route 149 in Marston Mills. That intersection, which suffered considerable traffic congestion for many years as a four-way stop, underwent a makeover in 1999. Despite some pubic opposition when the project was first introduced, town officials say there are now no traffic backups.

Nantucket plans to start construction in the fall on their first modern roundabout.

The Blinker light intersection has for years been a hazardous and frustrating junction for motorists.

According to the report, in 2002, when the intersection still had its namesake Blinker light, there were 10 accidents. That number dropped to four in 2003, and just two the following year.

"When the intersection was a two-way stop, the accident rate had been much higher than district or state averages for similar intersections," the report states.

The report determines that the use of bike paths along both intersecting roads is moderate, with approximately 50-100 bikes passing through hourly; less than half the volume of bikes and pedestrians that use the path on Beach Road between Oak Bluffs and Edgartown.

Anxiety about the intersection not only concerns safety, but also traffic volume and congestion. The report states that during the winter months the average daily traffic (ADT) on Edgartown-Vineyard Haven Road west of the Blinker is about 8,400 vehicles; this rises to upwards of 14,000 during the summer.

The report highlights an increase in costs to the Vineyard Transit Authority (VTA), since the change over to the four-way stop. The VTA currently has three bus routes running through the intersection.

Public opposition to the roundabout played a major role in the decision to abandon the plan for a small-scale rotary in 2004. The report refers to examples in other parts of the country, in which public support for a roundabout rose greatly after it was built.

The report cites a study by the Insurance Institute for Highway Safety, which states that, "American motorists often say they don't like roundabouts, but experience quickly wins them over."

The report addresses the issue of air quality, and states that the options that require all vehicles to come to a complete stop are the worst offenders.

"Automobile emissions and air pollution are increased when vehicles idle while waiting in stop-and-go traffic or at a traffic signal or stop sign," the report states. "Emissions also increase when vehicles accelerate, particularly from a standing stop."

The roundabout would have the best impact on air quality, as vehicles generally do not come to a complete stop, and there would be the least amount of general congestion.

In regard to installing a traffic signal at the intersection, a public opinion survey carried out by the MVC in 2004 indicated that only 40 percent of year-round residents and 34 percent of seasonal residents favored that option.

If a traffic light were to be in stalled, it would be the only one on the Island.