The first southbound train on of the newly routed Amtrak Cascades Seattle-to-Portland service derailed on a highway overpass on Monday morning, with two passenger cars falling onto southbound Interstate 5, striking motor vehicles.

[Updated 12/20/2017] Amtrak train 501, which had a scheduled departure of 6:45 am local time from Tacoma, "was part of a new service that launched Monday morning," reports CBS News. "The train is able to carry up to 250 people, but officials said there were about 75 aboard at the time of the crash." The derailment occurred in Pierce County.
‘‘The only car that is on the tracks is the rear locomotive," stated passenger Chris Karnes who was three or four cars back from the front. "There are several cars that are hanging over the overpass,’’ Karnes said in an AP report on the derailment which indicated that a "track obstruction" is seen as the likely cause.
The Amtrak Cascades travel between Vancouver, British Columbia and Eugene, Oregon, although train 501 only travels between Seattle and Portland. December 18 was the first day for the new schedule [pdf].
The new service refers to a new route between Seattle and Portland rated for a higher speed limit of 79 mph.The older route traveled along Puget Sound and involved many curves. Radio reports indicates that the train was traveling at 80 mph on a curve before the I-5 overpass with a speed limit of 30 mph. This will likely be a major aspect of the investigation by the National Transportation Safety Board.
"Several vehicles on I-5 were struck by derailed train cars tumbling down from the tracks above," Pierce County Sheriff's Department spokesman Ed Troyer said, reports John Bacon for USA TODAY.
"We have multiple fatals on the train, no fatals on the roadway," Troyer said. He said the number of fatalities had not been determined."
"Interstate 5 southbound near Dupont, about 50 miles south of Seattle, was closed after the derailment "and will be for some time," Troyer said. He said the derailment took place at about 7:40 a.m. local time.
The new route was part of a $180.7 million project. Monday was the first day of revenue service. Radio reports indicate that news reporters had rode the train between Portland and Seattle on Friday, Dec. 15.
Amtrak Cascades trains are designed for high-speed rail service," according to Amtrak.
Amtrak Cascades trains feature a special technology that uses gravity to tilt through curves while speed is maintained. This technology shortens travel time between Seattle, Washington, and Portland, Oregon, by 25 minutes.
[This story was updated with correct count for fatalities and correct information regarding the speed limit in the area of the crash.]
FULL STORY: At least 6 dead after train derails, falls onto Wash. highway

Alabama: Trump Terminates Settlements for Black Communities Harmed By Raw Sewage
Trump deemed the landmark civil rights agreement “illegal DEI and environmental justice policy.”

Study: Maui’s Plan to Convert Vacation Rentals to Long-Term Housing Could Cause Nearly $1 Billion Economic Loss
The plan would reduce visitor accommodation by 25% resulting in 1,900 jobs lost.

Planetizen Federal Action Tracker
A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

Wind Energy on the Rise Despite Federal Policy Reversal
The Trump administration is revoking federal support for renewable energy, but demand for new projects continues unabated.

Passengers Flock to Caltrain After Electrification
The new electric trains are running faster and more reliably, leading to strong ridership growth on the Bay Area rail system.

Texas Churches Rally Behind ‘Yes in God’s Back Yard’ Legislation
Religious leaders want the state to reduce zoning regulations to streamline leasing church-owned land to housing developers.
Urban Design for Planners 1: Software Tools
This six-course series explores essential urban design concepts using open source software and equips planners with the tools they need to participate fully in the urban design process.
Planning for Universal Design
Learn the tools for implementing Universal Design in planning regulations.
Caltrans
Smith Gee Studio
Institute for Housing and Urban Development Studies (IHS)
City of Grandview
Harvard GSD Executive Education
Toledo-Lucas County Plan Commissions
Salt Lake City
NYU Wagner Graduate School of Public Service