Flaw at L.A. light-rail junction poses derailment risk, experts say

Local transit officials have run into complications trying to fix a junction on the recently opened Expo light-rail line, where experts said a serious track flaw presented a higher risk of train derailments.

Officials of the Los Angeles County Metropolitan Transportation Authority believed they had found a permanent solution to a rail alignment problem where the Expo Line and Blue Line merge at Washington Boulevard and Flower Street just south of downtown Los Angeles.

However, the extra metal that was welded to a portion of track to keep trains moving smoothly as the Blue Line makes a 90-degree turn has had to be redone several times because of frequent wear, Metro officials say.

“We have been re-welding the section of track as it wears down,” said Michael Harris-Gifford, Metro’s executive officer of wayside systems. “We have no doubts yet about this being a permanent solution, but we need to see what is going on here.”

Metro officials had reported earlier that the results of the modification were encouraging and appeared to stop the abnormal wear of track and rail car wheel assemblies.

But on Wednesday, regulators with the California Public Utilities Commission, which oversees certain rail operations in the state, contradicted Metro’s assertion that wear was the problem. State officials said that a small part of the outer layer of the weld broke some time before July 6 and that the same weld also had broken in May.

Dave Sotero, a Metro spokesman, said the portion of track is set to be re-welded on Friday night. By adding a bulb of metal to thicken a key part of the rail, the repair is designed to reduce the damage to wheel assemblies as trains enter the turn.

First noticed in June 2010, the alignment flaw affects a portion of the junction used by southbound trains on the Blue Line, which runs between Long Beach and downtown Los Angeles. With 140 trips a day and 26 million annual riders, it is one of the busiest light-rail lines in the nation.

Though the metal bulb is a non-standard repair, Metro says the recent complications and the alignment problem have not endangered passengers or resulted in operating restrictions, such as slower speeds, for trains that now go through the junction.

As a condition of opening the Expo Line in April, the utilities commission imposed a stringent inspection program for the intersection. The agency plans to check on the welded portion of track.

The alignment problem has attracted the attention of several MTA board members, including Los Angeles County SupervisorsMark Ridley-Thomas, who has requested explanations from Metro, and Michael D. Antonovich, the new board chairman.

“Our office is extremely concerned about the issue and will work with MTA staff to find a solution because safety has to be the top priority,” said Tony Bell, a spokesman for Antonovich.

dan.weikel@latimes.com