Over the past several years, Fort Pierce Utilities Authority (FPUA) has hired Globaltech under a continuing design-build services contract to replace aging transfers pumps, which transfer treated water from the water treatment plant’s Lime Softening process to the ground storage tanks.

In three separate projects, Transfer Pumps 1, 3 and 5 were replaced with larger capacity pumps equipped with variable frequency drives (VFDs). The projects also called for replacing the pipe and valves from the pumps to the discharge 90-degree bend.

Globaltech prepared mechanical and electrical drawings for each new transfer pump installation, then furnished and installed 60HP vertical turbine pumps to replace the existing 40HP pumps.The new pumps were equipped with 60HP 6-pulse VFDs.

Project Achievements / Benefits

• Replacing the smaller, constant speed transfer pumps with larger, VFD-equipped pumps has given FPUA more operational flexibility and control. Previously, FPUA had to run multiple pumps at all times and manually balance their flows with flow control valves. Significant water elevation differences arose in the clearwell, making disinfection dosing more difficult and limiting backwash times. Now that the pumps have been upgraded, the desired transfer flow can be attained, if necessary, utilizing just one of the new variable speed pumps, providing better reliability and redundancy. Normal operation is for several pumps to run at reduced flows, which maintains the desired clearwell level, leading to better disinfection control and allowing for backwash operations at any time.
• Globaltech is currently preparing to replace a fourth (and final) transfer pump for FPUA in 2019.