Concrete slurry with aggregate was poured into 250mm, 375mm and 450mm (10”, 15”, 18”) sewer mainlines after boring into an unmarked sewer line during ground stabilization work in a coastal condo development near Los Angeles. The concrete blocked the sewage flow from nearby Marina del Rey towards the treatment plant.


The operator controls the 1000bar (14,500psi) water blast with eyes on the operation to cut its way through the aggregate and the concrete to break it into smaller pieces. The concrete removal from the three lines took multiple weeks to complete and saved the building project as construction could continue.