Norwich — Redesigning West Main Street-Route 82 with six roundabouts and a median divider to eliminate left turns is the best of several alternatives state transportation officials considered for resolving numerous traffic safety problems on the busy commercial strip, officials told more than 50 people Wednesday at a public information meeting.

The preliminary “concept project,” with a rough cost estimate of $42 million, would be the first location in Connecticut with multiple roundabouts and a median divider along a 1.3-mile stretch of commercial roadway, DOT Principal Engineer William Britnell said.

Several speakers from the audience expressed mixed views about the project — some calling it an excessive response to the safety problems that could be resolved with speed warning signs and traffic enforcement.

“I am stunned at this,” resident Kathleen Murphy said. “I've been a Norwich resident all my life. I think this is going to affect a lot of businesses.”

She questioned whether the project would solve the many traffic problems on Route 82 and asked that the entire project be reconsidered.

Others applauded the project, calling the plan a practical solution to one of the worst traffic hazard areas in the state.

About a third of the audience clapped at the end of the nearly two-hour informational meeting.

The plan calls for placing roundabouts at New London Turnpike, Norman Road, Dunham Street, Osgood Street, Mount Pleasant Street and Asylum Street.

A six-inch-tall median divider with landscaping would run from New London Turnpike to Asylum Street, prohibiting left turns, with side streets and driveways accessible by right turns only.

The existing four lanes of traffic, two in each direction, would be retained from the Interstate 395 Exit 11 intersection to Dunham Street.

From there to the red light at High Street, the roadway would be two lanes, one in each direction.

DOT Supervising Engineer Peter Talarico cautioned that the project still is in preliminary stages.

The agency next will explore community support, take concerns and suggestions into account and decide whether to go forward.

If the project goes forward, a second public meeting would be held once the design is 30 percent complete.

At that point, officials could better discuss final designs, property acquisition, pedestrian safety measures and other features, Talarico said.

“We want to make sure it has reasonable support before we commit significant resources to it,” Talarico said.

Much of the presentation prior to questions centered on the rationale behind the roundabouts.

Traffic crash data from 2010 through 2012 showed 462 crashes along the strip, with 169 injuries.

An unusually high number of crashes occurred at non-signalized intersections, with left turns and side-swipes by cars switching lanes to avoid a car stopped to make a left turn.

Nine locations along the strip are on the state list of high crash rate spots, with seven of those being in spots between signal lights.

A raised median was installed on Route 83 in Vernon and reduced turning crashes by 78 percent, with a 95 percent reduction in injuries, Britnell said.

While that road does not have roundabouts, Britnell said roundabouts slow traffic down while keeping it moving and improves pedestrian safety by allowing people to cross one lane at a time in the roundabout with “refuge islands” in between lanes.

In Salem, a roundabout that replaced a four-way signal intersection at routes 82 and 85 reduced crashes from 24 per year with nine injuries to six per year with less than one injury, Britnell said.

Residents peppered DOT officials with questions and comments following the presentation, including questions about how the frequent Southeast Area Transit bus stops would be handled, how pedestrians would cross without traffic and walk signals and how firetrucks at the East Great Plain Volunteer Fire Department would get through the New London Turnpike roundabout.

Britnell said the DOT would consider designing pull-off bus stops and additional crosswalks between roundabouts and flashing-light, audible pedestrian crosswalks in the roundabouts.

The roundabouts would be designed to accommodate 18-wheeler trucks and firetrucks, he said.

c.bessette@theday.com

Twitter: @Bessettetheday