The Second Avenue subway line currently under construction in New York City is one of the largest infrastructure projects under way in the United States.
According to the Metropolitan Transportation Authority (MTA) information,
The Second Avenue Subway will be New York City’s first major expansion of the subway system in over 50 years. When fully completed, the line will stretch 8.5 miles along the length of Manhattan's East Side, from 125th Street in Harlem to Hanover Square in Lower Manhattan. In addition, a track connection to the existing 63rd Street and Broadway Lines, will allow a second subway line to provide direct service from East Harlem and the Upper East Side to West Midtown via the Broadway express tracks.
In all, 16 new stations will be built, serving communities in Harlem, the Upper East Side, East Midtown, Gramercy Park, East Village, the Lower East Side, Chinatown and Lower Manhattan. The new stations will also provide transfers to other subway and commuter rail lines.
All of the stations will have escalator and elevator access including access for the disabled, and will feature climate control features to maximize customer comfort.
According to Adam Clark Estes’ latest Gizmodo post, the latest pictures from the MTA and Flickr show the scale of the tunnels and the stations that are being built below the city. The project, which took decades to plan and design, is becoming a reality through the efforts of some highly skilled, well-paid craft workers.
Check out the pictures below. By the way, the yellow “tarps” are permanent insulation and vapor barriers that will help keep the line dry when the concrete is poured and the trains start running and carrying 200,000 passengers per day.