Tech Brief: Lime Softening - Hard water can cause scaling problems in water heaters and soap does not lather well in hard water. Some water utilities soften water to improve its quality for domestic use. Lime softening is best suited to groundwater sources, which have relatively stable water quality. The combination of variable source water quality and the complexity of the chemistry of lime softening may make lime softening too complex for small systems that use surface water sources.
Tech Brief: Corrosion Control - Corrosion occurs because metals tend to oxidize when they come in contact with water, resulting in the formation of stable solids. Corrosion in water distribution systems can impact consumers’ health, water treatment costs, and the aesthetics of finished water. Various methods can be used to diagnose, evaluate, and control corrosion problems.
Tech Brief: Jar Testing - Jar testing is a pilot-scale test of the treatment chemicals used in a particular water plant.It simulates the coagulation/flocculation process in a water treatment plant and helps operators determine if they are using the right amount of treatment chemicals, and, thus, improves the plant’s performance.
Tech Brief: Taste and Odor Control - Complaints about the taste and smell of drinking water are all too common for many systems. This Tech Brief examines common taste and odor problems and provides techniques for dealing with them in the treatment plant.
Tech Brief: Turbidity Control - One of the water treatment operator’s primary jobs is controlling turbidity. Turbidity control is usually associated with surface water systems and groundwater systems under the direct influence of surface water. This Tech Brief examines turbidity control through the entire water treatment process from the raw water source to the clear well.
Tech Brief: Calibrating Liquid Feed Pumps - Liquid feeder pumps are used to inject various chemicals needed for effective water and wastewater treatment. Calibrating these pumps helps control and optimize feeding rates, which in turn provides better water quality at a lower cost. This Tech Brief discusses how to calibrate liquid feed pumps.
Tech Brief: Reading Centrifugal Pump Curves - Reading and understanding centrifugal pump curves is key to proper pump selection, and to their reliable and efficient operation. This Tech Brief examines how pump curves can provide data about a pump’s ability to produce flow against certain head, shows how to read a typical centrifugal pump curve, and provides information about pump efficiency and brake horsepower.
Tech Brief: Iron and Manganese Removal - Iron and manganese are common in groundwater supplies used by many small water systems. Exceeding the suggested maximum contaminant levels (MCL) usually results in discolored water, laundry, and plumbing fixtures. There are secondary standards set for iron and manganese, but these are not health related and are not enforceable. Small water plants may choose to either sequestrate or remove iron and manganese.
Tech Brief: Filter Backwashing - Backwashing a drinking water system filter means reversing and increasing the water’s flow to flush out accumulated debris and particles. Backwashing is not only vital to the life of a filter, it is fundamental to the quality of water coming out of the filter.