Chapter 24 - Designing for Easy Operation and Low Maintenance

Abstract

This chapter deals with the design considerations that reduce life-cycle costs by facilitating operation and maintenance (O&M) and by improving labor efficiency. It is primarily directed toward wastewater pumping but much of it also applies to water pumping and to sludge pumping. Landscaping the pumping station to fit or to blend into the surroundings is desirable, and so is designing the landscaping for low maintenance by using ornamental woody perennials and ground cover that require little attention. A flowmeter in conjunction with the pressure gauges facilitates checking the power consumed against the water output. The lengths of straight inlet and outlet pipe recommended by the manufacturer must be observed for all types of meters; otherwise, the meter readings would probably be erroneous. The errors increase exponentially as the inlet and outlet pipes are shortened. The electrical control panels must have a minimum clearance in front of at least 0.91 m (3 ft) for 0 to 150 V, 1.07 m (3 ft, 6 in.) for 151 to 600 V, 1.22 m (4 ft) for 601 to 2500 V, and 1.52 m (5 ft) for 2501 to 9000 V. The same clearance is required at the back if the panel is a free-standing unit. Free-standing panels are recommended over wall-mounted panels. Equipment and system-wide standards should be developed to minimize the need for equipment, O&M knowledge, and spare parts.