Construction crews this week kicked off a $31.1-million revamp of one of the most congested, pedestrian-unfriendly suburban roadways in Greater Boston.

Decades in the making, the Massachusetts Dept. of Transportation project will overhaul the 1.7-mile long Newton/Needham Corridor, a major commercial and retail artery just outside of Boston that is packed with both businesses and traffic, with an average daily vehicle count of 28,000.

Littered with curb cuts, the roadway has been marked by a free-for-all of traffic coming from all directions, making it difficult for pedestrians and shoppers to move from one store to the next – or simply cross the street – without getting back in their cars, noted Greg Reibman, president of the Newton-Needham Chamber.

The project includes a number of measures to help make it easier to get around, both by car and on foot, with plans to eliminate a number of curb cuts and synchronize traffic lights.

P. Gioiso & Sons Inc. is the prime contractor on the project, with D&R General Contracting Inc. and the Don Martin Corp. handling the paving, with work slated for completion in 2023.

"It's the biggest road construction project to touch our region in a generation," Reibman wrote in a blog post on the launch of the project. 

The corridor starts at the intersection of Winchester Street with Route 9 in Newton, and then continues down Needham Street before crossing a historic Charles River bridge to Highland Avenue in Needham.

One of the key features of the roadway revamp are plans for a wide sidewalk with space for pedestrians alongside a raised bike lane for cyclists. All told, the new sidewalk will be more than 11 ft wide, divided between a 5 ½-ft-wide bike lane and a 5 ½-ft space for pedestrians.

Cantilevered sidewalks will also be added onto the stone bridge over the Charles, which dates to 1875, for use by both cyclists and pedestrians.

The roadway at the heart of the corridor is also poised for a major makeover, with plans for two drive lanes and a center lane for left turns from both directions.

Traffic signals will be replaced at five locations, with two signals installed as well, including at the busy intersection with Route 9 at the start of the corridor.

The project has been on the radar screen for more than two decades, having been proposed as far back as the mid-1990s.

But competition for always scarce federal and state transportation dollars meant it eventually required a coordinated push by local officials in both Newton and Needham over the last few years to eventually move it up the list of eligible projects, the chamber’s Reibman said.

The long-delayed roadwork also kicks off a few months after the start of construction on major redevelopment of 28 acres of underused commercial buildings and lots along alongside the Newton stretch of the winding suburban corridor.

Developer Northland Investment Corp. is pushing ahead with plans for 1.1 million sq ft of new commercial and housing space, including 300,000 sq ft of new offices and shops and 800 housing units, of which 140 will be designated as affordable and rented out at below-market rates.

Despite the decades it took to get the revamp of the Newton/Needham Corridor off the drawing boards and into construction, there may have been a silver lining, noted one local official.

Thinking about transportation has changed significantly over the years, as can be seen with the addition of a 11-ft-plus wide sidewalk with space for a raised bike path.

“In the 20-plus years it has been in the making, it has allowed advances in transportation to catch up,” said Barney Heath, director of planning and development for the city of Newton.