WALNUT CREEK, Calif., Dec. 8, 2015 — Brown and Caldwell continues to do its part in rehabilitating  the nation’s aging infrastructure, earning accolades for the Orange County Sanitation District in the process, after a BC team designed and upgraded two deteriorated sewer force mains in Newport Beach, Calif., along the picturesque Pacific Coast Highway.

The pipeline project — one of the largest diameter (30- to 36-inch) installations of glass-fiber reinforced cured-in-place pipe (GFR-CIPP) that includes one of the longest CIPP liner inversion drives (1,013 linear feet) — has been recognized with a Trenchless Technology award for the Southern California district. Earlier, the project received the 2014 American Society of Civil Engineers, Orange County branch, award for Construction Project of the Year.

“The design and construction of this pipeline rehabilitation project was considerably complex from a technical, environmental and social perspective,” BC project manager Mark Briggs said. Benefits include extended service life, protection of coastal resources and public health, increased system reliability, and reduced risk of wastewater overflows.

The district’s 60-year-old Newport Force Main (NFM) consists of two parallel, interconnected ductile iron pipelines, with diameters varying from 20 to 36 inches. The NFM conveys up to 36 mgd of wastewater flow across more than five miles of pressure pipe along the PCH to the district’s treatment plant in Huntington Beach.

This project was essential for the district to maintain a reliable and effective wastewater collection system and to convey flows from three sewage lift stations in Newport Beach.

Briggs noted that “it has been a great experience applying advancing technologies for trenchless rehabilitation of force mains, which to date have lagged behind those developed for gravity sewer and potable water systems. Replacing under-capacity segments with upsized non-metallic HDPE pipe has also been key. Being a part of the OCSD mission to protect public health and the environment while endeavoring to mitigate a variety of risks and community impacts has been truly rewarding.”

Brown and Caldwell has led the evaluation of force main inspection technologies, developing inspection programs and providing condition assessments and rehabilitation design of force mains throughout the country. The firm is consistently ranked in Trenchless Technology’s annual Top 10 Design firms list, and to date, has completed the inspection and condition assessment of more than 1 million feet of wastewater force mains nationwide.

For the Orange County Sanitation District, more than half of the NFM system was rehabilitated using GFR-CIPP to reduce impacts to the community, businesses, tourism and the environment. New 32-inch HDPE was installed in a 42-inch microtunneled steel casing, and 150 linear feet of 24-inch HDPE was installed in a 36-inch bored and jacked steel casing to connect to the lift station.  In addition, 32- and 36-inch HDPE was used to replace the balance of project piping using traditional cut-and-cover techniques.

This is phase one of the two-phase project. Phase one focused on replacement piping, tunneling and rehabilitation of portions of the two-barrel system pipeline located on the south side of the Pacific Coast Highway. Phase two focuses on rehabilitation of the portions of the pipeline on the north side of the highway, which needed to remain in service during phase one, along with final abandonments and roadway restoration, and is expected to be completed in the spring of 2016.

Brown and Caldwell performed evaluation, design and construction support for the project, with Kiewit on board as the general contractor and Insituform serving as a major subcontractor.