Heavy rains last year in Arizona were a welcome and much-needed event, filling most lakes and reservoirs to capacity. Even though Arizona needed the precipitation, it caused interesting challenges along the way.
One challenge took place at Phoenix’s 91st Avenue Wastewater Treatment Plant, which has a capacity of 180 mgd. At the plant, effluent flows via gravity into the nearby Salt River, which is usually dry. As water from the upstream dams was released into the Salt River, the water rose to levels that had the potential to disrupt the plant’s discharge.
As the river level continued to rise, the level of the plant’s effluent rose and had the potential to back up into the plant. To eliminate the impact on the plant’s operations, the city of Phoenix determined it had to immediately install a temporary system capable of pumping up to 350 mgd from the plant’s effluent channel to the river.
The city of Phoenix requested Godwin Pumps of America, Inc. to propose deployment of a temporary pumping system capable of handling the full 350 mgd.
Godwin proposed a system consisting of 14 Godwin CD400M Dri-Prime 16-in. pumps, 14 Godwin DPC300 12-in. pumps and three large axial flow pumps. Because the pumps are portable and have the ability to automatically prime from dry, they are ideal for emergency installations, according to Ron Askin, Godwin’s western regional manager.
“With the largest fleet of portable diesel-driven pumps in the world and with one of our best distributors, Water Movers, Inc., I was confident we were the city’s best chance of beating the rising waters,” Askin said. “We committed to having the entire 350-mgd pumping system completely operational in 10 days.”
“We received word late in the day on Friday that we had the job,” Askin said. “We had five pumps on site the following Monday, and installation began immediately; by Monday night, two pumps were operational.”
The first delivery trucks were loaded late into the night from Godwin’s Corona, Calif., facility, 50 miles southeast of Los Angeles. Crews began work on Saturday morning. High density polyethylene suction and discharge pipes were fused and the first pumps placed. Multiple trucks arrived daily for the next five days, and a 10-man crew worked 10 to 12 hours a day until the system was complete.
On arrival, the pumps were placed on a 30-ft-wide dike road. Each piece needed to be brought in individually, making the installation more challenging to coordinate than on a more open site. Three forklifts, including a 30,000-lb machine, were used to offload and transfer the large pumps. A 60,000-lb crane was utilized to set each in place. Suction and discharge were connected, and each pump was tested as soon as it was installed. Because of the capacity each pump added as it was installed, the threat of the plant backing up diminished daily.
The entire setup was completed in eight days—two days ahead of schedule.