We were asked to evaluate the high service pump station (HSPS) at the Blendville water treatment plant in Joplin, Missouri. The high service pump station housed five constant-speed pumps ranging in rated capacity from 4 million gallons per day (MGD) to 9 MGD and with a firm capacity of 22 MGD. During typical operation, the high service pumps are controlled by water levels in the 4th Street elevated tank, which is the primary water storage supply for the main pressure zone. When the 4th Street tank is out of service, the configuration of the high service pumps must be such that the water treatment plant can continue to supply water to the distribution system.

We recommended variable frequency drives (VFDs) for the future high service pump arrangement. The addition of VFDs required upgrades to the electrical system to ensure that power distribution needs were met and there was sufficient backup power-generation capacity to run at least half of the high service pumps. Changes to the HSP configuration also involved upgrades to the finished water metering at the plant. 

A new building is being constructed to house six pumps with a firm capacity of 22.5 MGD. The pump bases and piping were designed to facilitate installing higher capacity pumps in the future. Portions of the existing building are being gutted of equipment and piping. However, the structure is not being demolished. The pump discharge manifold permits discharge to two separate mains that transport water from the pump station to the collection system. A concrete vault that houses a mag meter was installed on each of the discharge lines.