J-117A Interplant Pipeline Rehabilitation

This project is the first portion of a larger outfall rehabilitation program. Shimmick’s work for this contract consisted of civil and electrical site work including interplant water flow isolations, large pipeline rehabilitation, electrical duct banks, and misc. site repairs. The work was highly integrated and required well-coordinated flow isolations to maintain safe work conditions.  Shimmick’s work was performed at numerous locations at the facility and included the following:

• A new effluent junction box at Plant 1, which included installing new access hatches, installing a new slide gate, removing unneeded appurtenances, and electrical modifications.
• 84-inch diameter interplant pipeline and downstream 72-inch diameter overflow pipeline rehabilitation requiring repair at various locations within the pipelines with glass fiber reinforcement and carbon fiber reinforcement. Shimmick also installed joint seals to mitigate incoming leakage into the pipelines. This scope also included an 18-inch storm drain rehabilitation with approximately 185 linear-feet with a cured-in-place pipeline.
• 120-inch interplant pipeline and downstream west junction structure included the rehabilitation of each joint with the installation of Ameron flat sheet over the joints and the sandblasting and coating of each manhole over a distance of approximately 3.5 miles. This scope of work also included a 10-day plant outfall booster pump station shutdown.
• Concrete repairs, included work on the Santa Ana outfall wing walls, wet well topside concrete slab, and the ocean outfall booster station pipe pit.

This project was also used as a means for OCSD to relocate critical utilities that would impede construction of the new LOFLO Pump Station that will be built on a future project.