For this project, crews constructed a 30-ft-deep, below-grade pump station with three 21-million-gallons-per-day (MGD) medium-voltage pumping units and a 3-MW emergency generator. 

The existing force main shutdown and tie-in challenged the project team. The contractor had to remove an existing 60-in.-dia steel bend pipe section located 16 ft underground and replace it with a 60-in. wye and isolation valve. This valve connects the new pump station discharge piping to the existing force main piping. 

The contract specified that the team had one week to complete the tie-in, after which penalties of $15,000 per hour would be imposed. The team worked closely with the client and outside agencies to develop an hour-by-hour schedule for the critical tie-in. 

The team had materials and equipment standing by in case the primary plan was disrupted. Crews worked around the clock and completed the work in three days.

Safety was also a top priority because the project involved several high-risk construction activities, including deep excavations, confined space entries and multiple diver operations. The contractor ensured all workers were properly trained and comfortable with each task they performed.

Back to ENR California's 2020 Regional Best Project Shine