One look at a New Haven street map will show the beginnings of a highway extending from the interchange between Interstate 95 and Interstate 91. But this highway, also known as the Oak Street connector, has ended abruptly before the Air Right Garage for over 30 years. Although the state has recently decided to revive the project, New Haven Mayor John DeStefano Jr. wants to make one important modification — the building of “footings” below the highway.

Under the current plan, the Oak Street connector would be a four-lane, partially underground urban boulevard that extends from the I-95/I-91 interchange in the east to Ella T. Grasso Boulevard, and eventually to Route 34 in the west between North Frontage Road and Legion Avenue. DeStefano said he wants to modify the project, which is currently in its design phase, to include the building of “footings” in the first segment of the underground section of the highway, an area from the Air Right Garage to Howe Street between Oak Street and North Frontage Road.

“Don’t build it unless the state puts in footings that will allow us to cover the extension just west of the Air Rights Garage,” DeStefano said.

Footings are foundational structures that need to be built before the construction of the highway that would allow structures to be built above the highway. The city wants to turn the air space above the connector into commercial property, possibly as part of a biomedical science park.

“It would be much cheaper to put [the footings] in now than to do it later,” said Michael Piscitelli, the director of comprehensive planning at the New Haven City Plan Department. “To have additional loss of this area would be very detrimental to economic development in this area.”

The state Department of Transportation has expressed its willingness to comply with the city’s suggestions, but there has been some disagreement about who should fund the footings.

“We have been willing to incorporate the footings into the project,” said Tom Harley, the principal engineer at the Department of Transportation. “The issue is who is designing it, who is paying for it.”

The department first proposed a plan to build a connector to Route 34 in the 1950s. At the time, the plan was one of the first urban renewal projects aimed at bringing more visitors into downtown New Haven.

The original plan called for a six-lane, underground highway extending from I-95 and I-91 in the east to Derby Avenue in the west, and eventually to I-84. Under this plan, the connector would pass through the Oak Street neighborhood, dividing the Hill neighborhood from downtown New Haven.

For the project, the state acquired a 1.1 million square foot plot of land extending from York Street to Ella T. Grasso Boulevard and, in the process, forced many residents to leave the Oak Street neighborhood. But by the 1970s, the project had stalled. The connector was never completed, and the cleared area was left empty.

“They removed a real neighborhood, an organism with a lot of multicultural life,” said Karyn Gilvarg, the executive director of the City Plan Department. “Some people feel that this is an example of urban renewal gone wrong.”

In the 1980s, a new proposal by city economic development staff and the state Department of Economic and Community Development aimed at reviving the project. This new plan, not formally drafted until 1993, called for the cleared area to be turned into a biomedical science park lined by two landscaped, two-lane urban boulevards that would serve to connect Route 34 with I-95 and I-91. The city hoped to attract biomedical companies to the area, and city planners hoped the project would not only create jobs but also reconnect the Hill neighborhood to downtown New Haven.

The current plan has incorporated elements of the 1993 proposal.

“We’ve agreed to do it,” Harley said. “The DOT has only one functioning goal, and that is to create a Route 34 roadway.”