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Lane Construction Reaches Milestone on Northeast Boundary Tunnel Project

August 7, 2018


August 7, 2018 - The Northeast Boundary Tunnel (NEBT) project reached a significant milestone—the lowering of the tunnel boring machine (TBM) into the CSO-019N shaft located near Robert F. Kennedy Memorial Stadium in Washington, DC. The TBM is now ready to excavate the underground tunnel that will improve the quality of waters in Washington.

At 26-feet in diameter and weighing 650 tons, the massive machine, named Chris, will drive 27,000 feet underneath the city.

During a delicate 8-hour process, the machine was lowered down into the shaft in one piece. The hoisting system used 4 hydraulic strand jacks enabling the machine to be precisely placed at the bottom of the shaft. The strand jacks were paired to make a cradle configuration under the TBM. A total of 19 high-strength steel strands were suspended from each hydraulic jack.

It will take approximately 30 months to construct the tunnel, which is 5.5 miles in length. The entire project is slated for completion in December 2022. Once completed, the tunnel will connect with the Anacostia River Tunnel and the First Street Tunnel to provide a complete gravity combined sewer overflow collection system from northeast DC to the Blue Plains Advanced Wastewater Treatment Plant. All flows captured by the tunnel system will be delivered for treatment at Blue Plains prior to discharge to the Potomac River.

View the time-lapse video.

View the photostory.

To learn the story behind Chris, including how the TBM got its name, click here.

Read the project profile.

 

Posted in the categories Featured Announcements, News.

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