Nearly four years after a deadly derailment, Amtrak Cascades trains safely rolled through the new Lakewood-DuPont trackway again Thursday, a quicker path than the former waterfront route around Point Defiance.

Sound Transit, which owns the 14-mile, $181 million inland track segment, says it waited to reopen the route until safety reforms were ready: satellite-based positive train control in the locomotives, a succession of speed limits and signs slowing trains from 80 mph to 50 to 30 before the DuPont curve, and extensive training of Amtrak crews.

Amtrak has said that eight trains — including Amtrak Cascades and Coast Starlight — will use the bypass daily, with additional trains added in the coming months as COVID-19 restrictions are expected to ease.

On Dec. 18, 2017, Amtrak 501 was on its inaugural run on the new, faster rail line when it went off the tracks near Olympia. Rail cars careened off an overpass onto morning rush-hour traffic on Interstate 5, and three people were killed and 62 injured.

The engineer said he didn’t see or didn’t recognize the signposts and signals indicating a drastic drop in the speed limit, a report from federal investigators said. The train went into a curve at 80 mph in a 30 mph zone before jumping the tracks.

It was the engineer’s second time operating a train in that direction on the newly opened stretch of track, known as the Point Defiance Bypass.