Many devices and services are on the market to improve drinking water quality. What devices are necessary depends on the contaminants to be removed. Have drinking water tested for coliform bacteria, nitrates, pH, total dissolved solids, hardness or iron and manganese before determining a treatment method. Bacteria and nitrates are of particular concern to private drinking water wells.
Common Water Treatment Devices and the Contaminants Removed
- Water softeners use a cation exchange process, regenerated with sodium chloride or potassium chloride, to reduce the amount of hardness in water.
- Activated carbon or charcoal filtration devices are most effective at removing organic compounds often responsible for taste, odor, and color problems. They can be used to aesthetically improve water. Activated carbon filters will also remove chlorine. These may be attached to a faucet, or a pitcher such as a Brita.
- Iron filters. There is not a health hazard from iron or manganese in water, but they can cause taste, staining and accumulation problems. Iron will cause reddish-brown staining of laundry, porcelain, dishes, utensils and even glassware. Deposits build up in pipelines, pressure tanks, water heaters and water softeners, reducing available quantity and pressure of the water supply.
- Reverse osmosis reduces levels of naturally occurring substances that cause water to be unappealing (foul tastes, smells or colors) and substances that have contaminated the water supply such as nitrate, sulfate, sodium and total dissolved solids. Reverse osmosis units with carbon filters may reduce the level of some man-made chemicals like pesticides, dioxins and VOCs (volatile organic compounds like chloroform and petrochemicals).
Selecting a Water Treatment Device and Provider
There are many water quality improvement methods. They include removing the source of contaminants, repairing or drilling a new well, connecting to a municipal or rural water supply, using bottled water, or installing a water treatment system. Here are some considerations for purchasing a device:
- Before investing in a water treatment device or service, get a water test at a certified lab to correctly identify the concern.
- If a dealer offers tests, be sure to get a written copy of the results.
- Has the system has been rated by the National Sanitation Foundation (NSF)?
- Maintenance: how much will replacement parts, filters, or chemicals cost? How often?
- How much water will be produced daily and how rapidly will it recharge?
- Water softener: be sure it recharges on demand, or as water quality indicates.
- Make sure the recharge water does not go into your septic system. Salts from a water softener, and the larger quantity of water can cause problems with septic system maintenance.
- Is there is an alarm or shut off device to notify of malfunctions?
- Within a month after having the system installed, have the well tested again - before and after it passes through the unit to determine how effectively it improves water quality.
How to Select the Right Water Treatment System?
Select the water treatment technology that suits the water conditions and delivers the amount of treated water needed. As a general rule, water treatment systems reduce concentrations rather than remove all of the contaminant.
The system should have the ability to remove contaminants to drinking water standards. The more contaminants present in the water, the higher level of treatment needed and the more stress on the system, reducing the lifespan of filters and membranes.
Determine if the unit fits the conditions that need correcting such as a softener, iron removal or foul smells.
Devices are either point of entry - serve the entire water supply such as water softeners; or point of service. Point of service devices are attached to a faucet, such as a carbon filtration device.
Maintenance of Water Treatment Systems
Regular monitoring and maintenance is needed as with any machine or device. Units need cleaning, carbon filters must be replaced as directed. Some systems have monitors that indicate performance or how many gallons of water have been treated. If there is a private well, regular water testing must be done to monitor nitrate and coliform bacteria.
How are Water Treatment Systems Regulated?
Federal and state governments do not certify water treatment equipment. Some states provide for testing of equipment; this will be documented on product information. The National Sanitation Foundation (NSF) is an independent laboratory providing testing and certification of drinking water treatment systems. They establish national, uniform sanitation standards and criteria. Their seal indicates that a product or material complies with the relevant NSF standard. Consider only purchasing a water treatment system that has the NSF listing for the health-related contaminant of concern. The Water Quality Association lists products in compliance with industry standards.
With some homework and research, homeowners can select an appropriate water treatment device.
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Valerie Prax - Valerie Prax recently retired after nearly 35 years with University of Minnesota Extension. She served as an Educator and Professor for 27 ...
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