How To Remove Bacteria From Water

How To Remove Bacteria From Water
There are countless harmless microorganisms around us all the time. But infectious microbes can cause illness or disease, especially when they enter your water supply.

Municipal water supplies disinfect water to eliminate waterborne pathogens, so homes on city water are usually free of disease. The EPA requires public water systems to regularly test for coliform bacteria (which is an indicator of pathogens in the water), and if detected to issue a public notice within 24 hours, telling you what to do to stay safe.

But If you get your water from a private well or other untreated water source, you are responsible for testing and treating your water to make sure it’s safe and healthy. Because you can’t always detect bacterial contamination by taste, smell, or sight, the only way to know for sure what’s lurking in your water is to test it.

If your water tests for or is at risk for pathogens, appropriate treatment solutions can eliminate the problem and protect your health and peace of mind.

What bacteria can be found in water?

The types of infectious microorganisms that may be found in your drinking water include bacteria, viruses, and protozoans.

Pathogenic bacteria

The microorganisms known as pathogenic bacteria are most likely found in unchlorinated private water supplies and stored water.

E. Coli (Escherichia Coli) is a type of fecal coliform bacteria found in the intestines of animals and humans. The presence of E. coli in your water is a strong indication of recent sewage or animal waste contamination. Rural areas with irrigation and agriculture are at higher risk of this bacterium infecting a water source.

During rainfalls, snow melts, or other types of precipitation, E. coli may be washed into creeks, rivers, streams, lakes, or groundwater. If these water sources are not treated or are inadequately treated, E. coli may end up in the drinking water.

Although most strains of E.coli live harmlessly in the intestines of healthy humans and animals, there is a strain that produces a powerful toxin and can cause severe illness.

This infection often causes severe bloody diarrhea and abdominal cramps. The greatest risk is to children under the age of five, the elderly, and people whose health is immunocompromised (i.e., people who have long-term illnesses such as cancer or AIDS).

Salmonella Enterica is most commonly spread by the improper handling of raw foods, such as chicken. But less frequently, it has also been associated with outbreaks from contaminated drinking water.

Colorado tap water was responsible for 79 cases of salmonella poisoning in 2008, which caused fevers and vomiting. In a study which looked at the water supply of Togo, Africa, 26 cases of salmonella contamination were found, suggesting that developing countries are at a greater risk for bacterial infections from drinking water.

Shigella is a group of bacteria that causes shigellosis, one of the most contagious types of diarrhea caused by bacteria. It is a common cause of waterborne outbreaks in the United States, but most of these outbreaks occur in recreational water (communal pools or lakes) rather than in drinking water. However, shallow, private wells can be at risk from storm runoff, agricultural waste, and broken sewage systems or septic tanks.


Parasitic infectious microbes can cause disease, and are about 100 times smaller than bacteria. However, viruses are less likely to be the source of infection in private wells than bacteria

Noroviruses cause intestinal illness, or gastroenteritis, and have been associated with outbreak on cruise ships and in communities, restaurants, camps, schools, institutions and families.

Rotaviruses cause intestinal illnesses and are the most common cause of severe diarrhea among infants and children. Before introduction of a rotavirus vaccine in 2006, about 55,000 children were hospitalized with rotavirus infections each year in the United States. Worldwide, more than 600,000 children die from rotavirus infections annually. However, most of these cases are not caused by drinking contaminated water.

Private wells can be contaminated by these viruses from the feces of infected humans. This waste can enter the well through sewage overflows, sewage systems that aren’t working properly and by polluted stormwater runoff.

Wells may be more vulnerable to such contamination after flooding, particularly if the wells are shallow, have been dug or bored, or have been submerged by floodwater for long periods of time.

Protozoans and Waterborne Cysts

Waterborne cysts are very common and found in most water sources.

Cryptosporidium and Giardia are the most commonly identified causes of waterborne illness in the United States.

These microorganisms are Protozoa with complex life cycles. They exist in a cyst form, very much like a microscopic egg.

When even a few cysts are consumed, they enter the small intestine, where they excyst, or "hatch," and can multiply into millions of protozoa. Giardiasis and Cryptosporidiosis are flu-like illnesses with symptoms involving persistent diarrhea, nausea, abdominal cramps, weight loss and sometimes dehydration.

Cysts enter the water through treated and untreated sewage discharges. Livestock are notorious carriers of Cryptosporidium, while beavers have been identified as a carrier of Giardia.

Once in the water, both protozoan cysts remain capable of infecting a host for many months, especially in colder water where they are more resistant to natural die-off.

Similar to spores, cysts tend to be more resistant to destruction by disinfection.

Solutions for removing bacteria from water

If your home uses city water, your public wastewater treatment system already uses many water treatment methods to provide safe drinking water. Disinfection by chlorine chemicals is the most commonly used treatment method, along with filtration.

For private wells or other untreated water sources, installation of disinfection or purification systems may be necessary to ensure your water is safe from harmful microorganisms.

Home water treatment devices treat water either where it enters the home (point of entry) or at the point where it comes out the tap (point of use.) The treatment solutions include Ultraviolet Disinfection, Ultrafiltration, Reverse Osmosis and Chlorine.

Ultraviolet (UV) Light Disinfection

The most effective treatment to protect your home from bacterial disinfection is a whole house Ultraviolet (UV) purification system. A chemical-free approach to disinfection, UV systems expose water to light at just the right wavelength for deactivating microbes, bacteria, viruses, protozoans and cysts that may be present in the water.

By deactivating the DNA of the bacteria and viruses, UV light removes their ability to multiply and reproduce, eliminating the normal threat to your health

Because these systems are installed at the point of entry to your home, they will protect the water coming out of every tap.

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Ultrafiltration systems filter down to 0.02 microns in size. While UV systems deactivate the bugs, Ultrafiltration removes them along with a wide range of other contaminants in the water.

Installed as an under sink point of use filter, this system could be paired with a UV system for ultimate peace of mind about your water purity.

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Reverse Osmosis

Reverse Osmosis (RO) systems are capable of removing particles smaller than one micron in size. Water is passed through a membrane filter with very small pores under high pressure to remove minerals and contaminants, including microorganisms.

Though capable of removing microorganisms, it is not recommended that you rely on reverse osmosis as the primary source for removing pathogens in your water.

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Chlorine Treatment

While chlorine is used by public water treatment systems to disinfect water supplies, it can also be applied to private wells for periodic disinfection.

“Shock chlorination” - where a strong dose of concentrated chlorine solution is introduced to the well to treat bacteria - may be used anytime a new well is bored, or a well pump is repaired or maintained.

While effective, shock chlorination does not guarantee permanent bacterial elimination over time, and can damage other water filtration equipment.

Common questions about bacteria removal

Can I boil water to remove bacteria?

In an emergency situation where regular water service has been interrupted, or the water supply has been infected - a “boil water” alert may be issued. Following proper boil water instructions can kill most disease-causing organisms that may be present in water.

Does a water softener help with bacterial growth?

Water softeners and most drinking water systems are NOT effective for treating water-borne pathogens. In fact, most product manuals for these systems state that they are “not intended for microbiologically unsound water”.

If bacteria is known is ongoing water testing needed?

The CDC recommends that private well owners conduct a water test every year, including a test for coliform bacteria, regardless of the results of previous tests.

While it isn’t practical to test drinking water for every type of bacteria, it is simple to test drinking water for coliform bacteria, which can indicate the presence of harmful pathogens in the water.

Any homeowner who has had issues with bacteria should continue to test the well regularly after disinfection to make sure the problem does not reoccur.

You should also test your well if flood waters come within 50 feet of your well, if your water changes in taste, appearance, or odor, or your well is opened for servicing.

Water treatment can eliminate bacteria safely

Bacterial contamination is one of the most serious water treatment issues a homeowner can face. While there are temporary fixes to an emergency situation - such as “shocking” a well with chlorine after a flood - the best solution will provide you with peace of mind over time.

Whether you can solve the problem with a filter at the tap, or should think about installing a treatment system to filter water for your entire home, Tier1 offers the products you need to fix your problems.

If you’d like a personalized recommendation for your home, the Technical Support Team at is available to chat or answer your call