By Andrew Tangel 

An Amtrak derailment in Philadelphia that killed at least six people Tuesday cast a pall over one of the busiest and most lucrative passenger rail routes in the U.S.

The Northeast Corridor, which runs between Washington, D.C., and Boston, is the national passenger railroad's moneymaker, churning profits that prop up money-losing long-distance routes elsewhere in the country.

Now, the Amtrak line that carries top government officials, corporate commuters and weekend travelers is grappling with what one railroad official called its deadliest accident in nearly three decades. It is believed to be the worst accident along the Northeast Corridor since 1987, when 16 people were killed near Baltimore after a Conrail train collided with an Amtrak train. The accident sparked several safety reforms.

As railroad officials and regulators began to assess the damage from Tuesday's wreck, the accident was expected to upend train service between major American cities for the rest of the week.

The incident comes as Amtrak--which relies in part on funding from federal and state governments for its operations--is pushing for funding to upgrade aging infrastructure along the Northeast Corridor and working on finishing the installation of an advanced signal system known as positive train control, which is aimed at preventing collisions and derailments.

The railroad has already installed the federally mandated system between New Haven, Conn., and Boston and was to complete work between New York and Washington by the end of this year, an Amtrak official said.

In Washington on Wednesday, House lawmakers debated a transportation spending bill that would cut federal funding for Amtrak operations in fiscal 2016 by 18%.

"The bill is a victim of the majority's policy of self-imposed austerity, " said Rep. David Price (D., N.C.), speaking at House Appropriations Committee debate on the bill. "As investigators continue to piece together the series of events that unfolded, this committee must renew our commitment to provide whatever assistance is necessary to ensure safety aboard passenger train systems."

Rep. Mario Diaz-Balart (R., Fla.) said the committee was awaiting the findings of the National Transportation Safety Board about the accident. "From those findings, Congress must look at what we can do to try to avoid this from ever happening again," he said. "I know that I speak for everyone, not only in this committee but around the country that our hearts, our prayers are with them."

For the 2015 budget year, which ends Sept. 30, Amtrak had $1.39 billion in federal funding for its operations, capital spending and debt service, according to the appropriations panel. The committee was considering a bill that would set 2016 funding at $1.14 billion, which included a boost in the operations budget but larger cuts to federal grants for capital spending and debt service.

Lawmakers met at a separate and previously scheduled House Transportation Committee panel hearing on Wednesday to discuss freight railroad oversight, during which the Amtrak accident came up. "While we don't yet know many details, we need to know how this happened and ensure the safety of the system and the millions of Americans who rely on the Northeast Corridor," House Transportation Chairman Bill Shuster (R., Pa.) said in a written statement.

While authorities declined to speculate on what caused the wreck, the Amtrak official said the train derailed in an area known as Frankford Junction.

The area features a sharp curve that has a speed restriction of 55 miles per hour, the official said. To the east, trains are allowed to travel up to 100 mph; to the west, 80 mph, this official said.

Northeast Regional trains, the type involved in Tuesday's wreck, can travel as fast as about 125 mph in this area of the Northeast Corridor, while Acela Express trains are currently restricted at 135 mph, the official said.

Amtrak officials have recently been touting rising Northeast Corridor revenue and ridership across the railroad.

Amtrak's Northeast Corridor had 11.6 million riders in fiscal year 2014, up 3.3% from 11.3 million the previous year.

The Northeast Corridor had an operating surplus of $496.7 million in fiscal year 2014, up from $390.1 million the previous year, the railroad has said.

Amtrak officials have been making cases publicly and to local and congressional leaders for increased funding for big-ticket infrastructure upgrades, including a replacement of a Hackensack River rail bridge in New Jersey that is more than a century old and frequently snarls train traffic when it fails to close properly.

They are also trying to secure billions of dollars in funding to dig two additional rail tunnels beneath the Hudson River. Amtrak officials have warned they may need to shut down one of the two existing tunnels between New Jersey and New York so they can repair extensive damage caused by superstorm Sandy in 2012.

Write to Andrew Tangel at Andrew.Tangel@wsj.com

American Tower (NYSE:AMT)
Historical Stock Chart
From Aug 2024 to Sep 2024 Click Here for more American Tower Charts.
American Tower (NYSE:AMT)
Historical Stock Chart
From Sep 2023 to Sep 2024 Click Here for more American Tower Charts.