Once the floc has settled to the bottom of the water supply, the clear water on top will pass through filters of varying compositions sand, gravel, and charcoal and pore sizes, in order to remove dissolved particles, such as dust, parasites, bacteria, viruses, and chemicals.
After the water has been filtered, a disinfectant for example, chlorine, chloramine may be added in order to kill any remaining parasites, bacteria, and viruses, and to protect the water from germs when it is piped to homes and businesses.
Water may be treated differently in different communities depending on the quality of the water that enters the treatment plant. Typically, surface water requires more treatment and filtration than ground water because lakes, rivers, and streams contain more sediment and pollutants and are more likely to be contaminated than ground water.
Some water supplies may also contain disinfections by-products, inorganic chemicals, organic chemicals, and radionuclides. Specialized methods for controlling formation or removing them can also be part of water treatment. Community water fluoridation prevents tooth decay safely and effectively.
Water fluoridation has been named one of 10 great public health achievements of the 20th century 1. Top of Page. Even though EPA regulates and sets standards for public drinking water, many Americans use a home water treatment unit to:.
Household water treatment systems are composed of two categories: point-of-use and point-of-entry External NSF.
Point-of-entry systems are typically installed after the water meter and treat most of the water entering a residence. Point-of-use systems are systems that treat water in batches and deliver water to a tap, such as a kitchen or bathroom sink or an auxiliary faucet mounted next to a tap.
I have contaminated water and a vulnerable immune system. For people whose immune systems have a lessened ability to defend against illness—such as pregnant women, the very young, the elderly, those on cancer chemotherapy, and those living with AIDS— the Centers for Disease Control and Prevention recommends the following:.
As mentioned above, if you do buy bottled, look for brands that have been treated with reverse osmosis, distillation, or filtration with an absolute 1 micron or smaller filter.
My water system is not listed as having violated any health-related drinking water standards. Does that mean I'm safe? For many systems—especially large systems that serve more than , people—you may be safe. However, there are weaknesses in the rules themselves. For example, many fairly common contaminants such as perchlorate, PFOA, and algal toxins are not federally regulated, so there would be no violation of EPA rules if they are found in your water.
Also, the rules about how often to monitor water may mean that spikes in contaminants between tests go undetected. Additionally, local officials could try to avoid submitting health-based violations to the state or the EPA, might not report samples showing violations, or might not take samples in the first place.
For peace of mind, have your water tested. Who can I talk to about my concerns regarding the quality of my drinking water? Contact your water utility, your city council members, and your mayor.
Express your concerns. Urge them to fix the problems and keep you informed about their progress. Contact your state and federal legislators and ask them to support funding for water infrastructure improvement projects.
Prevention through protections like these are key. The toxic chemicals have been showing up in milk around the country, prompting midwestern farmers to take a closer look at their land. Earthquakes, spills, and groundwater contamination—wastewater wells come with many risks and few rewards for Trumbull County residents. The state now requires its public schools to test their drinking water for lead.
The problem of how to dispose of nuclear waste has haunted the United States for six decades. If lead poisoning seems like a story from the past, think again: The toxic metal lingers in communities all over the United States.
America is facing its second lead crisis. This time around, the effects are less obvious, but no less worrying. Reverse osmosis can replace a number of steps in the water treatment process or reduce the number of chemicals added to water. More than one in every seven U. These are not regulated by a federal law known as the Safe Drinking Water Act. These people face the same contamination challenges as municipal water systems. The difference, individual families have to worry about their own cleanup and treatment — without help or funding from other community members.
Edwards and Virginia Tech colleague Kelsey Pieper collected water-quality data from more than 2, wells across Virginia in and Some were fine. Others had lead levels of more than parts per billion.
Homeowners are unlikely to ever realize they have such a problem with their own well. The researchers reported those findings in in the Journal of Water and Health. To remove lead and other contaminants, well users often rely on point-of-use treatments. This is usually some type of filter.
Some people may spring for the gold-standard treatment at home: a costly reverse osmosis system. By Laurel Hamers November 29, at am.
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