Joint Outfall “B” Unit 1A

On October 12, 2016, Spiniello Companies was awarded the Joint Outfall “B” Unit 1A Trunk Sewer Rehabilitation Phase 1 Project located in the City of Carson, California. The Joint Outfall “B” was constructed in 1957, with the largest RCP pipe available then, to service millions of users under the Los Angeles County Sanitation Districts (LACSD) service area. After 60 years of service, the 144” pipeline was in need of a major rehabilitation. Contract work included:

• Lining of approximately 5,017 LF of existing 144" diameter reinforced concrete sewer

• Rehabilitation of 15 maintenance holes

• Construction of 2 insertion pits

• Installation and maintenance of bypass pumping

• Grouting of annular space and site restoration

Project Details

To restore the structural integrity of the trunk sewer, which had moderate to severe structural damage resulting from hydrogen sulfide corrosion (H2S), LACSD chose the largest available fiberglass Reinforced Polymer Mortar Pipe (RPMP) available on the market to slipline the system - 126” inside diameter RPMP manufactured by Hobas Pipe USA.

The Trenchless Technology 2019 project of the year, Joint Outfall “B”, posed a major challenge due to significant flows along with several curves in the pipe’s alignment. Spiniello utilized information provided by laser profiling of the alignment to manufacture the mitered pipes to be placed within the curve sections. The pipeline had two major sections, each requiring an access pit for pipe insertion.  Additionally, two bulkheads were constructed to isolate the system and allow for man-entry. Given the large pipe size, complete isolation and full bypass, the Joint Outfall “B” was cleaned and lined via man-entry using specialty equipment.

This project was funded in part by the Clean Water State Revolving Fund through an agreement with the State Water Resources Control Board and California’s Clean Water State Revolving Fund. Los Angeles County Sanitation District (LACSD) has sliplined with fiberglass pipes since 1989, in over 45 miles of deteriorated sewers. LACSD is considered the single largest user of this pipe and rehabilitation method in the country.

The Joint Outfall “B” was a one-of-a kind project with unique challenges. The fact that the project was completed seamlessly and ahead of schedule, is a testament to Spiniello’s great expertise in this field of pipeline rehabilitation.