Recently, many people have talked to me about the Oak Bluffs roundabout. These talks left me with the impression that many people do not fully understand the project or the Martha’s Vineyard Commission’s role. And so, speaking for myself, I’d like to address some items.

First, this is a roundabout. It’s not a rotary. A roundabout is as different from a rotary as a dog is from an elephant. A roundabout is small. It’s about the same size as the existing intersection with a single lane of traffic moving slowly around a small, landscaped center island. There is one in Marstons Mills on Cape Cod. A rotary, such as the one next to the Bourne Bridge, is about four times larger and is multi-laned, allowing for fast-moving traffic and unpredictable driver behavior.

While rotaries are unpopular, roundabouts have been well received as safe, efficient, and pleasant traffic-calming measures. The MVC reviewed data showing that most people oppose roundabouts at first, but support them after construction of the first one in a community. One multi-state survey showed 31 per cent in favor and 41 per cent opposed before construction; but 63 per cent in favor and 15 per cent opposed after construction. The first roundabouts in Nantucket and Barnstable were opposed, but both are now well accepted.

Second, the roundabout is an Oak Bluffs project. The MVC has had only limited involvement.

In 2001, when the intersection was a backed-up, accident-prone, two-way stop, the Oak Bluffs Selectmen hired traffic engineers to study the situation. The engineers recommended installing a four-way stop but only as a temporary measure because “it would impose significant inconvenience/delays” with long back-ups on the Edgartown-Vineyard Haven Road by 2010. The engineers said that only a traffic signal or modern roundabout would provide a long-term solution. The selectmen decided to build a roundabout and started working on the design and funding. (The commission was not involved and Mark London was still working in Canada.)

In 2003, the selectmen converted the intersection into a four-way stop on an interim basis. They also asked the MVC to collect new data and analyze the long-term options. The MVC completed a study (in 2006) on the impacts of keeping the four-way stop, installing a traffic light or building a roundabout. The study did not make a recommendation.

In 2006, the selectmen reaffirmed its decision to go ahead with the roundabout. (The MVC only reviews projects as developments of regional impact when there is a referral from a town board. There was none in this case, nor was there a clear requirement to refer it.) The Martha’s Vineyard joint transportation committee (with representatives appointed by all Island town selectmen and the county commissioners) made the roundabout a high priority and included the project in its Transportation Improvement Program every year since 2006 to make it eligible for state and federal funding. The selectmen arranged that MassDOT take over the design and construction on the town’s behalf. Last April, MassDOT held a public hearing, after which it authorized completion of the plans, incorporating public comment. Last June, MassDOT engineers (Greenman Pederson Inc., or GPI) made another full presentation of the roundabout proposal at the Oak Bluffs town meeting, which voted by a large margin to accept temporary construction easements to allow the project to proceed.

In June 2011, the West Tisbury selectmen referred the roundabout to the MVC as a discretionary DRI. The MVC accepted this referral, promising to proceed expeditiously while following its procedures and affording everyone an opportunity to be heard. It held a public hearing over two evenings last September. The plans were very detailed. (The reference to 25 per cent plans — MassDOT terminology — describes the stage in the design engineers’ payments, not the amount of detail on the plans.)

The MVC reviewed the results of a third traffic study completed by GPI and validated by MassDOT. The results were similar to the 2001 and 2006 studies. The study concluded that summer delays with the four-way stop — typically eight minutes coming from Vineyard Haven — would get far worse with projected traffic growth. The roundabout would reduce these delays to 13 to 20 seconds.

The MVC carefully considered public input in light of technical testimony. Many of the 3,500 roundabouts built in recent years have been carefully studied, allowing traffic engineers to design new ones with a full understanding of the impacts. Some examples follow.

Some people said that large trucks would not fit. MassDOT testified that the roundabout is designed to accommodate all trucks licensed to use public roads, including 18-wheelers.

Some people said that they’d prefer traffic lights. However, there is evidence that traffic lights result in 60 per cent more accidents, three times more accidents with injuries, and 10 times more fatalities than roundabouts.

Some people said that delays on Barnes Road might revert to pre-2003 levels. But all three traffic studies showed that delays would be virtually eliminated with a roundabout.

The commission ultimately concluded that, on balance, the benefits outweighed the detriments, that this was a reasonable proposal, and that it would not prevent Oak Bluffs from proceeding.

In approving the proposal, the MVC imposed conditions to improve the design. This involved reducing the number of bus pull-offs and the size of platforms, and eliminating excessive sidewalks and walkways. Other conditions called for greater preservation of existing trees, eliminating unnecessary lighting, and improving the safety of the bike path crossing.

The Edgartown and West Tisbury selectmen have now sued the MVC over the roundabout decision. I disagree with what they have said about the project and the process. I strongly believe that the MVC reviewed the project carefully and that its conclusions will be given deference by a court.

Regardless of where they stand on the roundabout, the people of Edgartown and West Tisbury must decide whether it’s worth suing the MVC — at the cost of tens if not hundreds of thousands of dollars to Island taxpayers — to try to prevent Oak Bluffs from proceeding with its project. In my opinion, a lawsuit like this is bad for the Island. We have greater challenges than fighting among ourselves about how one intersection is configured.

Chris Murphy is chairman of the Martha’s Vineyard Commission.