The Pittsburgh skyline rises in the distance as an eastbound Norfolk Southern train passes through the Liberty Avenue Amtrak station on the Pittsburgh Line. Height restrictions through the North Side prevent NS from operating double-stack intermodal trains and auto multilevel rail cars over the line.

increasing rail Clearance heights in Pittsburgh

Norfolk Southern’s 22-state rail network is an important part of the nation’s freight transportation system. The ability to move freight safely, efficiently, and reliably by rail is essential to businesses and households and is a cornerstone of the U.S. economy.

Nowhere is this more critical than in Pennsylvania. Norfolk Southern’s operations in the Commonwealth are a core part of the company’s rail system and the movement of freight between the Midwest and the East Coast. 

To enhance the efficiency of freight rail movement through Pennsylvania, Norfolk Southern has proposed the Pittsburgh Vertical Clearance projects. As part of a public-private partnership with Pennsylvania and PennDOT, Norfolk Southern has developed a series of projects designed to increase the height clearance for trains moving through Pittsburgh and southwest Pennsylvania. 


The Merchant Street Bridge Project is a stand-alone, on alignment bridge replacement project.  The Merchant Street Bridge was constructed circa 1905 and consists of two skewed steel spans supported by stone masonry abutments and one intermediate steel bent. The ballast-deck superstructure is comprised of a concrete-filled riveted steel trough system that varies in length and width and carries four active railroad tracks. There is extensive steel corrosion within the cross girders and columns comprising the intermediate bent as well as throughout the riveted trough system. These conditions will be considered safety concerns within a few years and may pose a safety hazard to the railroad and the traveling public and a potential liability to other transportation entities if not addressed.

On this webpage, people can learn more about these projects. Included are documents that explain the purpose and need for the projects; a list of frequently asked questions; and information about the public involvement processes. To help keep the public informed, Norfolk Southern will post updates on this page as discussion of the projects moves forward.

Purpose and Need

The proposed Pittsburgh Vertical Clearance projects will enable Norfolk Southern to move freight and people more efficiently through Pittsburgh and southwest Pennsylvania and connect industries and businesses to consumer markets on the East Coast and in the Midwest. The projects support jobs, economic growth, and national goals relating to greenhouse gas emissions and fuel efficiency. They will improve both rail and roadway networks in Pittsburgh and Allegheny County.

Pittsburgh Vertical Clearance Projects Purpose and Need Statement

The proposed Merchant Street Bridge Project will maintain safe freight and passenger rail operations through Pittsburgh and southwest Pennsylvania and connect industries and businesses to consumer markets on the East Coast and in the Midwest.  The Merchant Street Bridge has reached the end of its useful life and engineering inspections have identified a need to address structural deficiencies that have the potential to create risks to current rail traffic and forecasted rail traffic increases.

Merchant Street Bridge Project Purpose and Need Statement


These reports have been prepared in accordance with the Pennsylvania State History Code.  

An open process: Meeting with the community

On June 26, 2018, Norfolk Southern held a combined open house for the Pittsburgh Vertical Clearance Projects and Mechant Street Bridge Project at the Children’s Museum of Pittsburgh to introduce the public to the projects. An estimated 300 to 400 people attended, including North Side residents and local government leaders. NS received more than 90 written comments at the meeting, with additional comments received later by email or postal mail. The projects remain in the preliminary phase and NS continues to seek comment on potential community impacts.

For information about the open house, including public notices, project boards displayed, and public comments received, view the Open House Summary document.


Norfolk Southern had planned to host a traditional public meeting for the Merchant Street Bridge Project, but that was not possible due to COVID-19 safety concerns. In lieu of an in-person meeting, NSR provided an online presentation and comment form to gather input on the project.  Comments were received from July 27, 2020 to August 26, 2020.

Learn more about the public involvement process for Merchant Street Bridge Project. 



The Environmental Document for the Merchant Street Bridge Project was approved by PennDOT on October 27, 2021.

Merchant Street Bridge Project Environmental Document 

FAQs: We’re glad you asked

People who attended the public open house and Consulting Party #1 had plenty of questions about the projects. They ranged from concerns about air quality and noise to why Pennsylvania tax dollars would be used to help fund the projects.

Read Norfolk Southern’s answers to the most frequently asked questions about the Pittsburgh Vertical Clearance Projects.

During the public involvement and consulting party processes, there were plenty of questions about the Merchant Street Bridge Project. The questions ranged from concerns about whether the Allegheny Commons will be affected to what the bridge and roadway design will be.

Read Norfolk Southern’s answers to the most frequently asked questions about the Merchant Street Bridge Project.

NS in Pennsylvania: An essential part of our rail network

Norfolk Southern operates more than 2,400 route miles of track in Pennsylvania, while more than 4,600 employees live and work in the Commonwealth. NS operates four intermodal terminals across Pennsylvania and serves three additional private intermodal terminals, including one in Pittsburgh. NS’ Harrisburg Intermodal Facility anchors the east end of the Pittsburgh Line, serving as a major transportation hub for shippers moving freight between Chicago and the mid-Atlantic region.

View a Fact Sheet to learn more about NS’ presence in Pennsylvania, including the railroad’s positive economic impact and the categories of freight NS moves in and out of the Commonwealth.

Rail intermodal: efficient, cost-effective, environmentally friendly

The Pittsburgh Vertical Clearance projects would create an efficient, reliable route for Norfolk Southern to operate double-stack intermodal trains and auto multilevel rail cars through the city’s North Side. A growing number of businesses are shipping goods on intermodal trains, and double-stack trains are the most cost-effective and environmentally friendly way to transport them.

Learn more about the benefits of rail intermodal at the Association of American Railroads’ webpage, Freight Rail & Intermodal.

Projects lOcator Map


Related Links and downloads

view from the rails


A Norfolk Southern train passes under the canopy at the Liberty Avenue Amtrak Station. The low height of the canopy prevents the passage of double-stack trains or auto multilevel rail cars


Two Norfolk Southern trains pass near the North Avenue/Brighton Road Bridge in Allegheny Commons. The existing bridge prevents passage of double-stack trains or auto multilevel rail cars, and the clearance needs to be increased.


Traveling on NS' current double-stack intermodal route through Pittsburgh, an eastbound double-stack train on the Mon Line passes Mount Washington in a section prone to landslides. The brown area in the photo is the site of a landslide two years ago that disrupted train traffic for 11 days. This area is near Highmark Stadium and Station Square.


The rail cars on the rear end of a Norfolk Southern train move under the Columbus Avenue Bridge, which is not tall enough to allow passage of double-stack intermodal trains or auto multilevel rail cars.