Ms. Hochul has said that building along the freight line would allow the Interborough Express to be finished faster and at a lower cost than starting from scratch. On Thursday, she said the ongoing Metro-North expansion would likely crowd the tracks needed to extend the Interborough Express to the Bronx.
The route would bring additional transit options to parts of Brooklyn and Queens that are unserved or underserved by the existing subway, bus and rail system, including many low-income neighborhoods where people do not have cars.
According to the feasibility study, more than 900,000 people live within a half-mile of the new transit corridor. Of those, about 70 percent are people of color, about half live in households with no cars, and about one-third live in households whose income is below 150 percent of the federal poverty line.
“This is a fundamental equity issue,” Mr. Lieber said. “Communities — disproportionately low-income and communities of color, who are not in the middle of our transit system — will be connected.”
The study also found that 260,000 jobs exist in the area that would be most immediately served by the Interborough Express. But the new transit line would also link up with 17 subway lines, providing better access to jobs across the region. It could also ease congestion: About half of commutes made between Brooklyn and Queens in the area near the new transit line are made by car, the study said.
The feasibility study — which was commissioned in 2020, before Ms. Hochul’s tenure — estimated that as many as 88,000 people could ride the new transit line each weekday. The transportation authority is aiming to have service run every five minutes during peak commuting hours.
In the areas along the proposed transit line, “there are more people in Brooklyn and Queens together who are going to jobs in their borough or into the other of the two boroughs than there are crossing the East River,” Mr. Lieber said. “We have to adjust our transportation system to deal with that.”
Ana Ley contributed reporting.