February 7: This Date in Los Angeles Transportation History

2007:  The U.S. House of Representatives repeals a 20-year-old prohibition on federal funding for subway tunneling in the Wilshire Corridor.

Earth pressure balance tunneling machine

Citing safety concerns following a March 24, 1985 explosion and fire near 3rd Street and Fairfax Avenue, California Congressman Henry Waxman had sponsored legislative language in 1986 that prevented federal funding for further subway construction under Wilshire Boulevard.

Following the incident, investigators found that methane gas seeping into an auxiliary room of a Ross Dress For Less store had caused the explosion.  At least 21 people were injured in the blast, including two critically burned.

Over time, safer tunneling technology evolved.  “Earth pressure balance” boring machines were developed as more advantageous over traditional tunneling machinery.

In 2005, Waxman worked with Los Angeles Mayor Antonio Villaraigosa to appoint a five-member peer review panel of independent tunneling experts to review a subway tunneling proposal using earth pressure balance technology.

In November, 2005, the panel reported that tunneling along Wilshire Boulevard and the operation of subway trains west of Western Avenue (where the project had been halted) could be done safely using new technology.

Their report detailed both general conclusions and detailed conclusions along with general recommendations, while also explaining the difference in boring technologies.

California Congressman Henry Waxman’s legislation (H.R.238 of the 110th Congress), cosponsored by Congressman Brad Sherman,  is passed by voice vote.

Tunnel boring, explained. (Click for more information)

Following the reversal of tunneling prohibition, Los Angeles County Metropolitan Transportation Authority CEO Roger Snoble released the following statement:

“Metro welcomes House passage of Congressman Henry Waxman’s bill.  We are glad the House voted to repeal a longstanding prohibition on the use of federal funds for subway tunneling in Los Angeles.   A world-class panel of independent experts agreed in November, 2005 that Metro can tunnel safely along the Wilshire Corridor.  Today’s vote in Congress affirms the findings of this panel and opens the possibility of securing federal money to extend our subway westward to help alleviate the area’s crushing traffic congestion.”
U.S. Senators Barbara Boxer and Diane Feinstein filed companion legislation in the U.S. Senate less than a week later.
At the time, Senator Boxer proclaimed:
“Today is a good day for Los Angeles.  This subway project is another important step to decrease congestion in Los Angeles.  We’ve been told this project can be done safely, so it’s time to move forward.”
Senator Feinstein added that:
“Several gridlock is a reality faced by millions of residents in Los Angeles every day.  But plans to expand the city’s Metro Red Line and to ofer direct connections from Downtown Los Angeles to the Pacific Ocean were delayed for more than 20 years because of serious safety concerns.  Experts have now assured us htat tunneling technologies have improved sufficiently to allay those concerns. It’s time to make this project a reality.”

The legislation became law following the December 3, 2007 approval of the Senate version (S.497).

The earth pressure balance machines were put into use for the construction of the Metro Gold Line Eastside Extension.

More photos and information about how they work can be found in the Winter, 2006 issue of Metro Quarterly and the December 9, 2005 issue of the MyMetro employee news digest.

Additional information about the Wilshire Corridor Tunneling Project peer review can be found in the American Public Transportation Association Peer Review Panel’s Final Report.