Types of Water Treatments & How to Choose

With so many types of water treatments available, choosing the right one for your needs can be confusing. Some treatment systems work better for removing specific contaminants than others. The purpose of water treatments is to improve the quality of the water, making it more acceptable for its intended use. The types listed below are used to treat drinking water, and are called point-of-use methods. They can be installed in your home where the water is being used. The most common types of systems available include the following:

- Distillation: In this process, the water is boiled and the steam is condensed into a clean container. When the water vaporizes, many of the contaminants are left behind as the steam moves to a different area of the unit to be cooled and condensed back into a liquid. This process effectively removes some contaminants that will not evaporate, like salts and sediment. However, you must also use a vapor trap or carbon filter to remove volatile organic compounds that will evaporate. Those contaminants that do not boil will remain in the distiller, which must be kept clean to function properly. One of the biggest disadvantages of distillation is that it can take up to five hours to generate one gallon of distilled water. This type of system is also typically more expensive than some of the alternatives, especially considering the cost of electricity to operate the unit.

- Reverse Osmosis (RO): This type of water treatment uses pressure to force water molecules through a membrane to remove larger contaminants. The membrane has very small pores, so contaminants cannot travel through it. Water that remains on the contaminated side of the membrane is flushed down the drain, while the purified water is collected from the clean side. This type of treatment can greatly reduce salt and most other inorganic material, as well as some organic compounds. It also removes microscopic parasites and viruses, as long as the membrane remains intact. RO systems are slower than some other types of treatment, but faster and less costly than distillation systems. One problem with this type of unit is that it wastes water. For every gallon of filtered water that is produced, two to four gallons of unpurified water is flushed down the drain. RO systems also do not remove some contaminants like pesticides, so an additional activated carbon filter may be necessary.

- Solid Block Activated Carbon (SBAC) Filters: Although there are many types of filters available, SBAC filters are the most effective for adsorbing many different contaminants. Activated carbon is a natural material that can be derived from various sources, including wood and coconut shells. Through the adsorption process, dissolved chemicals in the water stick to the carbon surface while the water molecules do not. SBAC filters have a large surface area and small pores for collecting contaminants. They are less expensive and easier to maintain than other systems. However, they do not remove soluble salts or other harmful minerals. It can be difficult to tell when the filter needs to be replaced based on the taste and smell of the water, so you must follow manufacturer's recommendations for filter replacement.

The key to finding the right water treatments is to learn about your water source and which contaminants are in it. If you use a municipal water source, those companies are required to provide water quality reports annually. Other factors that may affect the type of treatment will include how much water you use per day, and which option will have the lowest cost and least maintenance.