The $4.6 million roundabout under construction at the Riverside traffic circle is on schedule and is expected to be done by November or December, according to Bill Hillman, chief engineer for the Suffolk County Department of Public Works.
It will be “substantially complete to most people’s eyes” well before that, he added.
Some residents posting on social media had become concerned that the county had failed to follow the approved plans for the two-lane roundabout, claiming it still looked like a one-lane roundabout.
Mr. Hillman said the project simply isn’t done yet.
“We had our surveyors go out and survey the work and we are building it right to plan,” Mr. Hillman said. “It’s exactly to plan.”
Two locations in the roundabout will be one lane, as had been planned from the beginning, Mr. Hillman said. A leg heading north from the circle onto Peconic Avenue will remain one lane. But southbound traffic coming into the roundabout from Peconic Avenue will have two lanes.
Likewise, a small section just north of the former diner property and heading into Riverleigh Avenue will also be one lane, Mr. Hillman said.
“Riverleigh Avenue would have been much more complicated with two lanes going through this portion of it,” he said. “The same with Peconic Avenue. Because of the close configuration of the five legs, there would have been confusion and safety issues had we not done this.”
The rest of the roundabout will have two lanes going in and out, according to Mr. Hillman.
The difference between a traffic circle and a roundabout is that the approach angles on a roundabout are designed to make cars slow down, he said. The county feels roundabouts are safer.
“When you do have accidents in a roundabout, they’re traditionally much less severe because you generally don’t have high-speed, right-angle collisions,” Mr. Hillman said.
The county had originally wanted to eliminate one of the five legs on the roundabout, but a plan to close off Riverleigh Avenue was dropped after it met with opposition from residents.
Residents of Flanders, Riverside and Northampton also fought for years to get the county to fund the widening of the Riverside traffic circle.
In 2015, the county postponed the funding until 2018, prompting local residents to attend county Legislature meetings, where they convinced legislators to restore the funding.
Design work began on the project in 2011 and the county awarded the contract for the job to Pioneer Landscaping and Asphalt Paving of Kings Park in late 2016.
In January 2017, Mr. Hillman estimated it would take about two years to complete the work.