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Publisher Summary This chapter describes methods for determining the required capacity and pressure for water pumping stations, presents recommendations on selecting and sizing the pumps, discusses control methods for operating pumps and provides representative examples of pumping station design. Water pumping stations are usually designed to supply water to an area in which the required demand is reasonably well defined or could be projected to a reasonable degree. In a water distribution system, the demand is a combination of customer needs and fire flow requirements. Average annual per capita water consumption, peak hour, and maximum daily demands vary widely depending on factors such as climate, income levels, population, and the proportions of residential, commercial, and industrial users. Depending on the source and ultimate use of the water, raw water pumping facilities are generally a combination of only three basic components that include the raw water intake structure, the pumping facilities, and the screening facilities, which might or might not be required. Most raw water pumping facilities are shore installations. The intake might be placed below the lowest water level on record or the lowest level of reservoir drawdown determined by storage requirements. Heat, cold, wind, dust, precipitation, and moisture are natural elements that must be considered in the design of any waterworks facility. Weatherproof enclosures for electrical equipment and devices and well-maintained paint, coatings, and linings for pumping units, piping, valves, and appurtenances might be adequate in moderate climatic conditions.

Publisher Summary This chapter presents several mistakes in pumping station design that could be minimized by making periodic design reviews at various stages of design and acquiring extensive knowledge about the manufactured products and pumping station design. One of the mistakes is inadequate ventilation for control rooms containing AFD equipment. Consideration of the effect of the heat loads from AFD equipment in designing and sizing the ventilating and air-conditioning systems for such electrical control rooms is required. The presence of hydraulic resonance within a pumping system could result in very high-pressure pulsations, high vibration, loud noises, and premature failure of the pump and/or piping equipment. The best way to avoid hydraulic resonance is to calculate the expected resonance frequency while the piping system is being designed and make sure that it is well away from the vane-pass frequency of the selected pump. Wastewater systems are especially vulnerable to water hammer because of buildup of grease and foam in control devices such as air valves. Pilot-operated surge-control valves for wastewater are unreliable due to the potential clogging of pilot lines, so it is recommended to avoid them in wastewater pumping stations. The water hammer is to be avoided in wastewater force mains by controlling the pipeline profile and/or by adding flywheels to drivers.

Publisher Summary Several considerations are involved in the design of pumping stations. It is required to make sure all the environmental considerations are met before the pumping station design is begun. The site should be checked for archaeological findings, and local and state regulatory agencies that may have jurisdiction should be consulted. Several codes such as NFPA 820, NFPA 70, and NFPA 101 provide guidance for fire protection for installations such as pumping stations. In addition to these documents, the designer should focus on choice of materials and fire suppression systems. Requirements for the design of ventilation systems for wastewater installations are provided in NFPA 820. Designers should be particularly aware that control and electrical equipment require an environment that has proper temperature control and protection against atmospheric conditions such as hydrogen sulfide gas. Pumping stations should be designed to handle flows from the entire service area. A pumping capacity that is adequate for the fully developed service area is to be installed or a pumping and force main capacity that could handle both the current needs and those of the immediate future with an adequate provision for economically adding to the capacity in the future is to be installed at the pumping station. The positive-displacement pumps are employed for thick sludges because these sludges are thixotropic and, after immobilization, high pressures are required to start their movement.