Image courtesy of 1265Main.com

Boston Properties is moving ahead with the full buildout of the 94-acre former Polaroid campus in Waltham, a 1-million-square-foot office-lab project that would be accompanied with an extensive series of roadway changes at Route 128.

The developer submitted plans Wednesday to Waltham officials for off-site transportation projects that would accompany the development. They include construction of a new on-ramp from Main Street (Route 117) to Route 128, and widening of the existing Main Street overpass from four to seven lanes to accommodate traffic generated by the full buildout of the property, including new bicycle and pedestrian lanes.

The initial phase of the 1265 Main St. project was completed in 2016, including an office building initially leased to Clarks’ shoes and a retail center anchored by Market Basket.

Because developers estimated the full buildout would generate nearly 19,000 vehicle trips daily, the remaining buildout was required to be accompanied by the road projects. According to a draft environmental impact report submitted to the Massachusetts Environmental Policy Act office, the developers offered to pay for designs but requested that the Massachusetts Department of Transportation pay for the transportation construction costs.

Boston Properties did not return a message seeking comment. A 2019 presentation described the extensive changes to the roadway network, including a new connection from Main Street to the Route 20 rotary, and an additional lane added to the Route 128 northbound off-ramp.

A Waltham Conservation Commission hearing is scheduled for 7 p.m. tonight.

The second phase of the project was originally scheduled to begin in 2020, but suburban office development hit pause at the onset of the pandemic.

The lease-up of one nearby project completed in 2022, Hobbs Brook Real Estate’s 507,000-square-foot 225 Wyman St. project, illustrated the potential success for new office construction in core suburban submarkets.