How common is coliform in well water?

Coliform bacteria are one of the most common water contamination problems in private water systems in Pennsylvania and throughout the United States. A 2006 survey of 450 private wells found coliform bacteria in approximately 35 percent and E. coli bacteria in about 15 percent of private wells.

Is coliform common in wells?

Various types of Coliform live in the soil and even on surfaces in your home, but they do not occur naturally in groundwater. If Coliform bacteria (sometimes reported as Total Coliform) are found in your well water, it is an indication that disease-causing bacteria could get in the same way.

What should you do if coliform is present in well water?

When coliforms have been detected, repairs or modifications of the water system may be required. Boiling the water is advised until disinfection and retesting can confirm that contamination has been eliminated. A defective well is often the cause when coliform bacteria are found in well water.

How much coliform is acceptable in well water?

The Maximum Contaminant Level (MCL) for bacteria in drinking water is zero total coliform colonies per 100 milliliters of water as established by the EPA.

How do they fix well with coliform bacteria?

A chlorine solution is the simplest and most effective agent for disinfecting a well, pump, storage tank or piping system. Liquid household bleach is the most commonly available source of chlorine. Regular Purex or Clorox may be used, but DO NOT USE LAUNDRY DETERGENT with bleach added.

Well Water Safety Module 5: Total Coliform in Well Water

Will shocking a well get rid of coliform?

When done properly, shock chlorination will kill all the bacteria existing in a well. A recent Penn State study of wells contaminated by coliform bacteria found that shock chlorination and installation of a sanitary well cap successfully removed the bacteria for one year in 15 percent of the wells.

Do water filters remove coliform?

Biological contaminants such as coliform bacteria are most effectively eliminated through chlorine disinfection, filtration, ultraviolet irradiation, and ozonation.

Is it safe to shower in water with coliform?

Drinking water used for brushing teeth should be of safe water quality (e.g. boil water for one minute, bring water from a safe source, or buy bottled water). Showering with water that is bacterially unsafe (total coliform positive, E. coli negative) has a far lower risk of illness than drinking this water.

What happens if you drink water with coliform bacteria?

Most coliform bacteria are not harmful. However, some can make you sick. A person that has been exposed to these bacteria may have an upset stomach, vomiting, fever, or diarrhea. Children and the elderly are more at risk from these bacteria.

What does a positive coliform test indicate?

What does a positive coliform test result mean? A positive coliform test means possible contamination and a risk of waterborne disease. A positive test for total coliforms always requires more tests for fecal coliforms or E. coli.

How common is bacteria in well water?

The occurrence of bacteria in water is common, treatable, and in most cases, preventable. The ideal situation is to have no bacteria in drinking water, although most bacteria in water wells are harmless and pose little health risk. Ground water in the majority of properly constructed drilled wells is bacteria free.

What is considered a high coliform count?

Sometimes, coliform bacteria results are reported as "TNTC" (too numerous to count) or "confluent." TNTC means that the bacteria concentration was so high that it could not be counted (generally higher than 200 colonies per 100 mL).

What is the Total coliform Rule?

The rule requires all public water systems (PWSs) to monitor for the presence of total coliforms in the distribution system at a frequency proportional to the number of people served.

How is coliform removed from water?

How Do I Remove Coliform Bacteria From My Drinking Water? The water can be treated using chlorine, ultraviolet treatment system or ozone, all of which act to kill or inactivate E. coli. Systems using surface water sources are required to disinfect to ensure that all bacterial contamination is inactivated, such as E.

Can you shower in contaminated well water?

Bathing poses no risk, unless you have open wounds, and make sure that children do not swallow the bath water. Continue taking these precautions until a test shows your water is free of bacteria, she said.

What temperature kills coliform bacteria?

The World Health Organization (WHO) notes that bacteria are rapidly killed at temperatures above 149°F (65°C). This temperature is below that of boiling water or even a simmer.

Can a water softener cause coliform?

Coliform and other bacteria can remain trapped in water softeners and filters and grow and multiply. You can easily have a situation where the water coming from the well is no longer contaminated, but the water becomes contaminated after passing through the water softener or filter.

Can you brush your teeth with E. coli water?

It is NOT safe to use contaminated water to brush your teeth! Instead, use boiled or bottled water. To treat water, fill your pot with water and heat it until you see bubbles reach the top.

How do you know if your well water is contaminated?

How does coliform get into water?

Coliform can enter your well through groundwater, surface water run-off, cracked or broken well parts, poor construction, and leaking septic tanks. Coliform in your well water can mean there are disease-causing organisms such as E. coli.

How often should you chlorinate your well?

Homeowners with private wells should have their well water tested every 3 to 5 years for some contaminants, including bacteria.

Should you put Clorox in your well?

You can disinfect your well with household chlorine bleach such as Clorox, Purex or a generic brand. The chlorine in the bleach kills bacteria. Note that it may take more than one chlorination for your well to return a satisfactory test.

How long should you wait to drink water after you chlorinate a well?

Allow chlorinated water to stand in the well and pipes for at least 8 hours (preferably 12 to 24 hours). Run water from outdoor faucets to waste (away from desirable vegetation) until the chlorine odor is slight or not detected at each faucet. Then run indoor faucets until there is no chlorine odor.

Is E. coli a coliform?

E. coli is a sub-group of fecal coliform. When a water sample is sent to a lab, it is tested for total coliform. If total coliform is present, the sample will also be tested for either fecal coliform or E.