Harriet the tunnel boring machine reaches Crenshaw/LAX Line’s Leimert Park Station

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LeimertTBM20Oct2016-118

Photo by Steve Hymon/Metro.

Photo by Juan Ocampo for Metro.

Photo by Juan Ocampo for Metro.

For your use: high-res pics here.

And there it is, shortly after 9:15 a.m. on Thursday. This means that one of the twin tunnels on the northern part of the Crenshaw/LAX Line alignment has been excavated.

The TBM will now be taken apart, trucked back to Expo and Crenshaw and then put back in the ground and reassembled. At that point the TBM will dig the other of the twin rail tunnels.

Click to see larger.

Click to see larger.

The underground section will include three of the eight new stations being built as part of this project: Crenshaw/Expo, Martin Luther King, Jr. and Leimert Park.

Harriet the TBM was lowered into the Crenshaw/Expo Station in February and then began digging its way south in April and reached the MLK Station in August and then resumed digging in September. The tunnel just completed is about one mile long.

The Crenshaw/LAX Line is expected to open in fall 2019. As part of today’s break-through, Metro CEO Phil Washington also announced that the firm building the project for Metro — Walsh Shea Corridor Constructors — has agreed to do the civil work, grading and other prep work for a ninth station along the alignment at Aviation Boulevard and 96th Street. The environmental studies for that project are ongoing.

That station will be used by the Crenshaw/LAX Line, the Green Line and numerous bus lines by Metro and other agencies. The station — also known as the Airport Metro Connector — will be the transfer point to the LAX automated people mover that will take riders to three stations at the airport terminals.

And some more pics. The top one was taken in the tunnel just south of Leimert Park Station looking south toward the tunnel entrance between 48th Street and Vernon Avenue.

LeimertTBM20Oct2016-54-Edit

And a few other randoms from this morning:

LeimertTBM20Oct2016-98 LeimertTBM20Oct2016-90 LeimertTBM20Oct2016-156 LeimertTBM20Oct2016-175 LeimertTBM20Oct2016-229-Edit

LeimertTBM20Oct2016-232 LeimertTBM20Oct2016-184-Edit LeimertTBM20Oct2016-41-Edit LeimertTBM20Oct2016-194

Categories: Projects

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14 replies ›

  2. Steve: You mention that: “The TBM will now be taken apart, trucked back to Expo and Crenshaw and then put back in the ground and reassembled. At that point the TBM will dig the other of the twin rail tunnels.” Do you know why they don’t just turn the TBM around at Leimert and then tunnel back north to Expo? It seems that would be faster, cheaper and easier. I’m sure there’s a reasonable engineering reason, but I haven’t heard it.

    • Here’s the answer from Metro construction staff:

      There is a great deal of support that is needed for the TBM at the Expo Yard launch point. There is an electrical power substation just to power the machine. The cranes, trucking, etc. that remove the dirt and supply the concrete tunnel segments are located there. The contractor would have had to duplicate or move all of that support equipment and get more real estate at the south end to turn the machine around and relaunch. These are some of the biggest reasons that the TBM has to mine from north to south on both tunnels starting at the Expo Yard.

      Steve Hymon
      Editor, The Source

  8. I wish civilians could tour the site, because I find this stuff so fascinating!

  9. Uh, Steve, looks like you linked to the high resolution versions above – it’s been many minutes on my DSL connection and all of the pictures still aren’t visible. The first pic is 4928 x 3280 pixels.