The Zone 3D and 4A Improvements Program, 24th St. Water Treatment Plant (WTP) Booster Pump and Pressure Reducing Valve (PRV) Stations Project in Phoenix, Arizona, plays a pivotal role in the city's strategic response to a reduced water supply allocation from the Colorado River. Historically, the Colorado River has been a vital source for the north Phoenix area. This initiative is designed to ensure a dependable water supply for the greater Phoenix region.

The project involves the interconnection of [RM1] two major water sources for Phoenix using the new booster pump station and integrated PRV station. This system facilitates the pumping of water from the Salt River to North Phoenix while also providing the flexibility to back feed the Colorado River water supply to South Phoenix.

Construction included an impressive 76-million-gallons-per-day booster pump station. This station features vertical turbine pumps set in below-grade pump cans, alongside a surge system that includes a suction surge tank and two 150,000-pound discharge tanks. The comprehensive infrastructure includes the installation of 66- to 84-inch-diameter suction and discharge piping, and aPRV station, complete with 13 specialty valves. The pump station is equipped with control valves, isolation butterfly valves, gate valves, and various instrumentation components for enhanced operational efficiency.

A major challenge encountered during the project was the delayed delivery of pump cans due to pandemic-related disruptions – a potential 80-day delay. The client's top priority was meeting the schedule to maintain a reliable water supply. Working with the City of Phoenix, the team took immediate action and fabricated the pump cans locally. This decision allowed the team to mitigate the delays caused by the supply chain disruptions and keep the project on schedule.

The PCL team identified a value engineering opportunity in the form of an innovative pipe tie-in. Originally, the plan called for the demolition of an existing concrete structure and its replacement with a shoring system. Through collaborative discussions with the client and designer, the team devised a more efficient solution that saved approximately $300,000. Instead of demolishing the structure, only the top of the building was removed, leaving the below-grade building and foundation to remain in place as a shoring sytem. The new pipe was then installed through the old structure underground. This innovative approach not only resulted in significant cost-savings but also reduced the project timeline.