Water purification is a two-step process of disinfecting water and removing contaminants. Coliform bacteria are one type of impurity that might be present in your water. It is one of about 90 contaminants that the U.S. Environmental Protection Agency monitors for its drinking water standards. For total coliform, the standards do not allow the presence of any total coliform bacteria. Total coliform is a measure of the entire amount of these type of contaminants that are present. Removal through filtration or other method is essential.
Coliform bacteria are naturally occurring microorganisms that are found in topsoil and surface water. Other types of coliform include fecal coliform and E. coli, which come from human and animal feces. Coliform bacteria can enter the water system through agricultural runoff into surface water sources such as streams and lakes. Nearly 75 percent of all the freshwater used in the United States comes from these sources, according to the U.S. Geological Survey.
The occurrence of coliform in the water indicates the possible presence of disease-causing bacteria from fecal matter. These bacteria can cause a host of human health issues, including gastrointestinal distress, headaches and other problems. Removing total coliform from your water is an effective way to prevent health conditions caused by these bacteria.
Filtration alone will not remove all harmful bacteria. Carbon filters, for example, will remove organic compounds from your water, explains the Minnesota Department of Health. A reverse-osmosis system will further filter your water by passing the water through a semi-permeable membrane through the use of water pressure, according to Purification Engineering Corp. A submicron filtration system will remove microscopic-sized particles, reports Cyber Nook. However, to effectively get rid of disease-causing bacteria, you will need to use a disinfection system in combination with your filtration system such as a distillation, chlorination or ozonation water treatment device.
Your water filtration system will require some maintenance to ensure it is performing at optimal levels. Your maintenance schedule will vary with the type of unit in which you use. A carbon filter will require periodic filter placements to prevent the build-up of bacteria and other contaminants on its surface. The maintenance required for reverse osmosis systems is based on estimated water use. Advanced Purification Engineering Corp. recommends changing the prefilters of a multifilter system annually. Other filter parts might last up to seven years.
No matter what type of water filtration system you use, water testing is the only way to know whether your water is free of total coliform, according to Iowa State University. If you are on a private well, you should test your water annually. However, if you live near a livestock operation or agricultural lands, you should test your water more frequently. This is especially important if you or a family member has reoccurring episodes of gastrointestinal distress, recommends the EPA.
- U.S. Environmental Protection Agency: Drinking Water Contaminants - List of Contaminants and Their MCLs
- U.S. Geological Survey: Surface Water Use in the United States
- LookD: Water Treatment Devices for Home Use
- Cyber Nook: Drinking Water Treatment Methods
- Purification Engineering Corporation: Frequently Asked Questions-Reverse Osmosis Systems