The Lake Huron Water Treatment Plant (LHWTP) supplies water to 59 wholesale customers. The facility began operation in 1973. The high service pump station houses eight (8) vertical pumping units and associated piping, valves, electrical gear, and auxiliary services. LHWTP has five GE 5500HP vertical synchronous pump motors (13.2 kV).
At 45 years of age, much of the pump equipment has reached or is nearing the end of its useful operating life. In 2017, the LHWTP staff found it more difficult to maintain the aging high lift field cubicles. High-lift pumps discharge treated water into arterial mains and operate under higher pressures. Failure in a critical component will render a high lift pump motor unusable unless upgraded to modern standards.
GLWA-DB-173 is a design/build contract awarded to Rotor Electric of Michigan, LLC, to provide upgrade solutions and implementation for a single high lift field cubicle at the LHWTP. The main issues relate to the existing DC rotating excitation system.
The scope of services for this project includes addressing all facility modifications required to install the new field cubicle components including development of system isolation plans, and all aspects of putting the equipment back into service while minimizing disruption to the water supply system. Disruptions in high service water flow must be carefully planned and coordinated with GLWA Water Supply Operations staff based on seasonal and diurnal fluctuations in water demands from customers.
High Lift Field Cubicle Repairs
Rotor has been charged with the professional engineering and construction services including completion of selective demolition of a single cubicle and construction of the repairs for each designated portion of the cubicle. This includes relays and controls, termination strips, installation of a 120V cubicle heater and thermostat to prevent further corrosion, and the addition of an automatic power factor control from the excitation system.
Upon successful completion of the work on the first high lift field cubicle, GLWA may expand the project to include the remaining four units.