By Jared Ebersole in Video — 28 Mar 2026

Why the Second Avenue Subway Became So Expensive

The Second Avenue Subway took nearly a century to open three stations because every delay made the next version harder and more expensive.

The Second Avenue Subway is not expensive because New York suddenly forgot how to dig.

It is expensive because New York waited until digging became the hardest possible version of the job.

Where to ride it

86th Street Station, Second Avenue and East 86th Street, New York, NY 10028.

The idea is almost a century old. After World War I, New York's subways were crowded and the city was still thinking in grand expansion maps. A Second Avenue line would relieve the East Side, replace elevated service, and run the length of Manhattan. Early plans imagined far more than the short piece riders use today.

Then the city kept missing its window.

In the late 1920s, the line was part of a sweeping subway expansion plan. WNYC's history of the project notes an early $86 million estimate. The Great Depression crushed the city's ability to build. By 1939, scaled-back plans had a projected cost of roughly $249 million, and World War II pushed major public works aside again.

The need did not disappear. The Second Avenue Elevated closed in 1942. The Third Avenue Elevated closed in 1955. That left the Lexington Avenue line to carry the East Side's subway burden for generations. The city removed the old elevated lines before the promised subway replacement arrived.

In the 1970s, New York finally started digging pieces of the Second Avenue Subway. Then the fiscal crisis hit. Construction stopped in 1975, leaving short tunnel segments sealed underground like archaeological evidence of an abandoned future.

The modern project restarted in 2007 and opened to riders on January 1, 2017. Phase 1 added three new stations, at 72nd, 86th, and 96th Streets, plus a connection to the existing Lexington Avenue-63rd Street station. AECOM describes the project as a $4.45 billion, 1.8-mile first phase. That is the kind of number that makes the line infamous: roughly $2.5 billion per mile, or close to half a million dollars per foot if you divide the total by the new route length.

The easy reaction is outrage.

The more useful question is what the money bought.

The early subway was built by tearing open streets, digging shallow trenches, building the tunnel box, and covering it back up. That method is disruptive, but it is simple compared with modern work under a fully built city. By the 2000s, Second Avenue was no longer a loose corridor waiting for infrastructure. It was packed with utilities, foundations, traffic, businesses, apartment buildings, hospitals, schools, and residents who could not simply pause their lives for a decade.

So the tunnels were bored deep underground. Tunnel boring machines helped avoid some of the utility chaos closer to the surface, but deep tunnels create another problem: deep stations.

Stations are where subway costs explode.

A tunnel between stations can be relatively simple: a tube with tracks, signals, ventilation, drainage, and emergency systems. A station is a cavern, a building, and a vertical transportation system all at once. Riders need entrances, escalators, elevators, mezzanines, fare control, ventilation plants, emergency exits, fire systems, communications, power rooms, waterproofing, artwork, finishes, and enough space to move crowds safely.

Second Avenue's new stations are unusually large by New York standards. The MTA's own descriptions note 615-foot platforms and overall station lengths that can run far beyond the platform itself to house equipment and access. At 86th Street, the platform is about 93 feet below ground. That depth requires long escalator runs and more underground volume before a rider even reaches the train.

Then there is the city above.

Excavating station caverns under dense Manhattan means managing building foundations, settlement risk, noise, blasting, trucking, utility relocation, street access, legal fights, community impacts, and the basic fact that the subway system keeps running 24 hours a day. The construction site is not a blank field. It is a surgical operation under one of the most expensive neighborhoods in the country.

The 1970s tunnels did help. Phase 2, which will extend the line north to Harlem-125th Street, is designed to reuse a tunnel segment built decades ago between 110th and 120th Streets. State and MTA announcements have framed that reuse, along with other lessons from Phase 1, as part of a plan to cut future costs.

But the underlying lesson remains.

Every generation that delayed the Second Avenue Subway made the next generation's version more complicated. The city removed the elevated lines, filled the corridor with more people and buildings, packed more utilities under the street, raised modern safety standards, and then finally asked engineers to build the missing subway beneath all of it.

That is why the Second Avenue Subway feels both miraculous and maddening.

New York did build it.

It just waited until the bill had become part of the story.