125th Street Subway Tunnel
Have your say on the subway tunnel planned under 125th Street
The MTA plans to dig a new subway tunnel under 125th Street, from Lenox Avenue west to 12th Avenue. Before it builds, it must study how the work would affect the neighborhood, and it is asking the public what that study should cover.
Comment deadline
Friday, November 13, 2026
Comment period: October 7 to November 13, 2026
The project
What’s happening and why it matters
The MTA wants to reuse the tunnel boring machines that will dig Second Avenue Subway Phase 2. It says building this tunnel right after that job saves money and time. Comments sent now help decide what its environmental study looks at.
A tunnel now. Stations later.
The project under review is a tunnel and nothing else: two side-by-side tubes deep under 125th Street, one for each future track. It would have no tracks, stations or power yet.
It would add some permanent structures above ground:
- A ventilation shaft with a permanent building at each end of the tunnel
- Two smaller shafts with kiosk-size structures at street level, somewhere along the route
The MTA says their exact locations and sizes are “currently being developed.”
Why now
The two tunnel boring machines that will dig Second Avenue Subway Phase 2 are due to finish that job at 125th Street in late 2028. The MTA wants to reuse them right away instead of bringing in new machines later. It says this could save hundreds of millions of dollars and more than two years.
What comes later
The MTA’s long-term goal is crosstown subway service under 125th Street. Its project page describes a line from Lexington Avenue to Broadway, and its 2025 feasibility study looked at up to three new stations: at Lenox Avenue, St. Nicholas Avenue and Broadway. Stations and tracks would need their own design and a separate environmental review. The review open now covers only the tunnel.
This “tunnel only” project would include the new tunnel, access shafts for egress to and from the tunnel, and ventilation equipment.
MTA Draft Scoping Document, §1
Once trains run
164,000 riders a day
The MTA’s early forecast for an average weekday on the full 125th Street subway, about 5,500 of them new transit trips (Draft Scoping Document §3.2).
Sources: MTA Draft Scoping Document §1, §2, §3.2, §3.4.1, §3.4.2 · MTA FAQ · MTA project page · Feasibility Study
Where the work would happen
The tunnel route is set. Most construction sites are not. The MTA says their locations are “still being developed,” and the Draft Environmental Impact Statement will describe the potential staging sites.
- Proposed tunnel (route known)
- Location not yet chosen
- Ground improvement (known block)
- Second Avenue Subway Phase 2, under construction
- Possible future station, not part of this project
Known
- The route: under 125th Street from about Lenox Avenue west to about 12th Avenue, then north to end between about West 131st and 138th Streets, near the Henry Hudson Parkway. §3.4.1
- Ground improvement, which strengthens soil before digging, is needed between Lenox Avenue and Adam Clayton Powell Jr. Boulevard. Some methods need work from the street surface. §3.4.2
- On that same block, Second Avenue Subway Phase 2 is building its own ventilation building, “Ancillary A,” and a construction site on the south side of 125th Street. §2, §3.4.2
Not yet decided
- The east-end construction site. It would handle workers, deliveries, storage of large concrete tunnel rings, removal of rock and soil, and a slurry treatment plant that processes the wet soil and rock from digging. §3.4.2
- One or two west-end sites, used to lift the machines out of the ground. §3.4.2
- The permanent shaft buildings at each end, and the two kiosk-size shafts in between. §3.4.1
- Other places that may need ground improvement, including the shaft sites. §3.4.2
Sources: MTA Draft Scoping Document §2, §3.4.1, §3.4.2, §5.2.2 · MTA FAQ · Possible stations: Feasibility Study
Timeline
- 2024New York State funds a feasibility study.
- December 2025The MTA completes the 125th Street Subway Feasibility Study.
- January 2026The Governor announces $25 million for design and environmental review of the tunnel.
- October 7 to November 13, 2026 NowPublic comment on the Draft Scoping Document, with three public sessions.
- After the comment periodThe MTA publishes a Final Scoping Document. Date not yet public.
- Winter 2027The MTA releases the Draft Environmental Impact Statement, followed by another public comment period.
- Late 2027 or early 2028Construction would begin with about 12 months of site setup.
- Late 2028The Second Avenue Subway machines finish their tunnels and become available. About 12 months of digging under 125th Street would follow.
- Late 2029 or early 2030Tunnel complete.
- LaterStations and tracks, after their own design and environmental review. No date is public yet.
Construction
About two years
The MTA expects the east and west staging sites to be in use for the whole construction period, about two years, with workers, trucks and deliveries coming and going. Its contractors would follow traffic plans worked out with the city’s Department of Transportation (§3.4.2).
Construction dates are the MTA’s current estimates, “based on current conceptual design,” and may change.
Sources: MTA project page (2024, January 2026, Winter 2027) · MTA FAQ (comment period) · MTA Draft Scoping Document §1, §2, §3.4.2
What the environmental review will study
The Draft Scoping Document lists what the Environmental Impact Statement will cover. Each topic looks at effects during construction and after the tunnel is finished. Scoping comments can say what is missing or what needs a closer look. After the comment period, the MTA will publish a Final Scoping Document that “reflects comments received, as appropriate” (§1).
The 18 topics the review will study
- Land use, zoning and public policy §5.2.3
- Socioeconomic conditions: people, housing and business activity, including business displacement and property needed for shaft sites §5.2.4
- Community facilities: schools, libraries, police, fire and health care §5.2.5
- Open space: parks, plazas and playgrounds §5.2.6
- Shadows from the new shaft buildings on open space §5.2.7
- Historic and cultural resources, including archaeology §5.2.8
- Natural resources §5.2.9
- Transportation: traffic, transit, pedestrians, street safety and parking §5.2.10
- Noise and vibration during construction §5.2.11
- Air quality during construction §5.2.12
- Greenhouse gases and climate change §5.2.13
- Energy §5.2.14
- Contaminated materials in the soil or groundwater §5.2.15
- Public health §5.2.16
- Disadvantaged communities §5.2.17
- Smart growth §5.2.18
- Mitigation: ways to reduce any significant harm the review finds §5.2.19
- Alternatives to the project §5.2.20
Left out of detailed study
- Urban design and visual resources
- Water and sewer infrastructure
- Solid waste and sanitation
The MTA’s reason: the project “would consist of an underground tunnel with limited above-ground structures and no new permanent workers or other permanent activities.” §5.1
Details worth knowing
- Vibration: the review will estimate vibration from building the shafts. Vibration from the tunnel boring machines will be described in words, not measured. §5.2.11
- Businesses: the study screens for six issues, including direct and indirect business displacement and harm to a specific industry. §5.2.4
- Getting around: the study covers lanes, parking, sidewalks and bus service on 125th Street during construction. Deeper analysis starts if construction adds 50 or more vehicle trips, or 200 or more pedestrian or transit trips, in a peak hour. §5.2.10
- Alternatives: the project will be compared with “No Action” (no tunnel) and with other ways to build it. §5.2.20
- Both projects at once: combined effects with Second Avenue Subway Phase 2 construction will be discussed “where relevant.” §5
Source: MTA Draft Scoping Document, sections 1 and 5. Section numbers follow the document’s body headings; its table of contents numbers them one lower from Shadows (§5.2.7) on.
Get involved
How to take part
Learn more at a public session, then send your comment by Friday, November 13, 2026.
Public scoping sessions
Online · Zoom
Thursday, October 22
12 noon to 2 pm
By phone: +1 646 828 7666
Webinar ID: 165 350 9093
Online · Zoom
Thursday, October 22
6 pm to 8 pm
By phone: +1 646 828 7666
Webinar ID: 165 740 5876
In person
Tuesday, October 27
5:30 pm to 8 pm
Adam Clayton Powell Jr. State Office Building, Community Room, 2nd Floor, 163 W 125th St
Bring a government-issued photo ID.
Registration is on the MTA’s website.
Three ways to comment
The MTA’s online form
Send your comment straight to the MTA. Open the MTA form
MTA Government & Community Relations
Re: 125 Street Subway
2 Broadway, D16.94
New York, NY 10004
Read the MTA’s questions and answers in your language
Our view
Where the BID stands
The 125th Street BID supports the tunnel. It is a big project, and we want it to be the best it can be, with the least disruption to our neighborhood and businesses. The more voices the MTA hears, the better.
Read more
Project documents
PDF · October 2026
Draft Scoping Document
What the MTA proposes and what its environmental review will study. Comments respond to this document.
PDF · 8 languages
Frequently asked questions
Plain-language answers about the tunnel, construction and the review.
Public scoping session notice
The MTA’s flyer with session dates, times and places.
PDF · December 2025
125th Street Subway Feasibility Study
The MTA’s study of the full subway line, including three possible stations.
Web page
MTA project page
News, session links and the official ways to comment.
Web page · October 7, 2026
State environmental notice
New York State’s official notice that the review has started.
Template letter
Start from a sample letter
A sample comment letter you can use as a starting point. Add your own details before you send it.
