New York State Route 747

Plans initiated by then-governor Nelson Rockefeller changed that. With supersonic transport (SST) considered at the time to be the next major development in air travel, Rockefeller wanted New York to have an airport that could handle both the SSTs and regular jets. Accordingly, plans were drawn up for a major expansion of the airport.

The state moved to condemn much of the land between Drury Lane and Maybrook in order to more than double Stewart's size. Families that had lived there since the Revolution fought bitterly. Eventually they were all evicted, but only after the state had promised never to develop the land and American SST development was canceled due to rising fuel costs.

The new route of 747, left, forking from Drury Lane, middle, at the Catskill Aqueduct, right.

In the years that followed, environmental and business activists in the region clashed over what to do with the 7,400 acres (30 km²) west of Drury. The former saw the recreational and conservation possibilities of keeping it a protected area; the latter pointed to ideal real estate in a region that was beginning to lose its job base.

The privatization of the airport in 2000 led the state to finally begin construction of the interchange, after Governor George Pataki designated much of the western lands as Stewart State Forest. It was stalled for three years by a lawsuit filed by several national and local environmental groups alleging that required environmental reviews were not properly conducted. On November 21, 2005, a compromise was reached in which most of the land that had not been designated as part of the state forest was and 400 acres (1.6 km²) near the exit was made available for development.[3][4] Construction of the exit and the surrounding roads proceeded apace.

Drury Lane as it was could not serve to bring the kind of traffic a major airport would handle. The road would have to be widened to at least four lanes and realigned. The presence of the aqueduct also complicated matters greatly. New York City's Department of Environmental Protection insisted that any new roads over the aqueduct bridge it to protect the aging pipeline from damage that vibrations from trucks passing overhead could cause.

The cut for the new access road.

Since Drury crosses the aqueduct north of the interstate on relatively level ground, a bridge would have added considerable expense to the project. However, a federally required 1999 value engineering study recommended instead rerouting Drury to make a four-way intersection at Stone Castle Road and Route 17K. While at the time there were some other issues seen as holding this up, eventually this was the option chosen.

The access road required some deep cuts to keep it level at the intersection with Drury Lane. Bill Gorton, NYSDOT's regional design engineer, compared it to the initial construction of I-84. "We tell our young engineers to take a good look at what we're doing here because chances are they won't see anything like this again in their careers", said Rashid Shariff, DOT's engineer in charge.[5] Over 1,000,000 cubic yards (760,000 m³) of dirt were moved. A quarter of that was used to fill a ravine the road crosses; the rest will be used as needed on the airport property.[5]

Southern terminus as of 2007. Old route on left; current route being constructed on right

The project's design took into account several considerations for rare or endangered species native to the area, which earned it an Exemplary Ecosystem Initiative award from the Federal Highway Administration. These included the construction of 12 vernal pools adjacent to the road to provide habitat for the Blue-spotted Salamander and Jefferson Salamander and box culverts to allow them to safely cross under the road, avoiding tree removal during the season when Indiana bats are roosting, and siting new wetlands to avoid impacting Purple milkweed.[6][7][8]

Prior to the project, Drury Lane had been maintained by Orange County as County Route 54. In February 2007, it was announced that the highway would become state-maintained and be designated as NY 747 once the project was completed.[2] On July 30, 2007, Route 747 was de facto open. Drury Lane was closed off north of the aqueduct and traffic was routed onto the new roadway between both termini, and on the new overpass. Road crews began removing the pavement from the former roadbed and dismantling the old overpass.

The 1.25-mile (2.01 km) long east–west airport access road from Route 747 to the main terminal, International Boulevard, was opened on November 20, 2007, officially completing the $55 million project.[9] Although NYSDOT refers to this access road as Stewart Boulevard in their press release, all area signage refers to the access road as International Boulevard, a last-minute change by the Port Authority of New York and New Jersey.[10]