With rain occurring about 100 days a year in Portland, wastewater volumes often exceed the city's sewer system capacity, resulting in untreated overflows into the Willamette River. The East Side Combined Sewer Overflow (CSO) project is part of a massive tunnel construction program that will virtually eliminate combined sewer overflows into the river.
The Kiewit-led joint venture of Kiewit-Bilfinger-Berger (KBB) completed Phase 1 of the East Side CSO project, a $1.5 million Preconstruction Services contract. Phase 1 included design review and assist, a cost estimate and schedule, and development of project-specific programs such as safety, quality and subcontracting plans.
Based on KBB's exemplary performance during Phase 1, the team was awarded the $381 million Phase 2 contract, the single largest component of Portland's CSO program. Referred to as "the Big Pipe," Phase 2 is the largest public works contract ever awarded by the City of Portland.