Water Treatment Overview
Qualified, dedicated, and capable water treatment plant operators are responsible for providing potable, palatable water to the public 24 hours each day and 365 days each year. To do so requires operators to understand basic conventional treatment processes that are key to ensuring drinking water quality and preventing waterborne disease.
Raw Water
Before treatment, water taken from the ground or from a surface source is called Raw Water.
Water characteristics differ from one source to another. Each aquifer or surface source has water of a different quality and chemical profile that will determine what type of treatment it should receive.
Groundwater
Groundwater is raw water that’s taken from wells. * Characteristics: Usually clear enough and clean enough that the only treatment needed may be to just add a chlorine disinfectant. * Requirements: All water, regardless of its origin, requires disinfection before entering the distribution system. * Additional Treatment: At times, groundwater may need treatment to address undesirable aesthetics (tastes, odors, or color).
Surface Water
Surface water can come from lakes, rivers, reservoirs, or the ocean. Depending on the source, the water’s characteristics will determine the necessary treatment.
- Low pH Waters: May require pH adjustment at the treatment plant.
- High Salinity: May require advanced membrane treatment to remove salt.
- Minimum Requirement: At the very least, raw surface water will need treatment to remove solids, followed by some form of filtration and chemical disinfection.
Water Treatment Categories
Water Treatment involves any process in which a source water’s quality is improved for drinking, irrigation, industrial uses, and many other applications.
1. Conventional Treatment
These are traditional, time-tested physical and chemical processes used to improve water quality from source to tap. * Goal: To protect public health, these processes remove various drinking water contaminants in accordance with the US EPA National Primary Drinking Water Regulations. * Operator Role: Operators must manage, maintain, and repair facilities. Performing these duties successfully requires good judgment and an understanding of the fundamentals.
2. Advanced Treatment
It is becoming vital for operators to understand advanced treatment processes, as many utilities are starting to use newer technologies (such as membranes) to address specific water quality challenges.