Is It Safe to Shower in Water With Coliform Bacteria

What are coliform bacteria and how do they originate in water supplies?

Coliform bacteria are a broad group of rod-shaped, gram-negative, non-spore-forming organisms found in soil, surface water, and the digestive tracts of warm-blooded animals. They enter water supplies through runoff, failing septic systems, or compromised well casings. Many people assume that finding coliforms automatically means the water is contaminated with sewage, but this is inaccurate. Total coliforms often originate from harmless environmental sources like decaying vegetation or soil. Only specific subsets, such as E. coli, serve as definitive indicators of fecal contamination and potential human pathogens.

What are the potential health risks associated with skin contact with contaminated water?

While intact skin acts as a robust barrier against most waterborne bacteria, contact with contaminated water can still lead to localized infections or systemic issues if the skin barrier is compromised.

• Folliculitis: This inflammation of hair follicles often appears as small, itchy red bumps or pus-filled blisters after exposure to contaminated water.
• Dermatitis: Prolonged contact can trigger skin irritation or rashes, especially in individuals with pre-existing conditions like eczema or psoriasis.
• Otitis externa: Water trapped in the ear canal after showering can create a breeding ground for bacteria, leading to painful swimmer's ear.
• Staphylococcus: Bacteria entering through minor abrasions or cuts can cause secondary infections, potentially requiring medical intervention if they spread.

How can coliform bacteria enter a residential plumbing system?

Coliforms frequently infiltrate residential plumbing through physical breaches or pressure changes. When a well pump fails or a pipe develops a pinhole leak, the system can experience a drop in pressure. This negative pressure acts like a vacuum, drawing in groundwater from the surrounding soil or nearby septic drain fields. A common example is a cracked well cap that allows surface runoff to seep directly into the well column during heavy rain.

An exception exists in newer, properly sealed systems where backflow prevention devices are installed. These valves stop water from flowing backward into the main supply line, even if pressure drops. However, even the best plumbing is vulnerable if the initial source water is compromised, as bacteria can form biofilms inside pipes. Once these colonies establish themselves on the interior surfaces of your plumbing, they can persist and shed bacteria into your water long after the initial contamination event is resolved.

What specific precautions should be taken if a 'boil water' advisory is in effect?

During a boil water advisory, you must heat water to a rolling boil for at least one minute to neutralize harmful pathogens before using it for any task that involves ingestion or mucosal contact.

• Drinking: All water intended for consumption, including that used for brushing teeth or making ice cubes, must be boiled first.
• Cooking: Use boiled or bottled water for washing produce, mixing powdered formula, or preparing soups to prevent accidental ingestion of bacteria.
• Washing: Hands should be cleaned with boiled water or sanitized with a high-alcohol hand rub after using the restroom or before handling food.
• Dishes: Manual dishwashing requires a final soak in a solution of one tablespoon of unscented bleach per gallon of water to ensure safety.

Can coliform bacteria be absorbed through the skin or enter the body during bathing?

Yes, bacteria can enter the body through orifices or compromised skin, though transdermal absorption is not a primary route. If you have a cut or abrasion, pathogens can bypass the skin's natural defenses, increasing the risk of infection by an estimated 10 to 50 percent depending on the bacterial concentration.

What are the recommended methods for disinfecting a private well or water system?

Disinfecting a well typically involves "shock chlorination," which requires introducing a high concentration of chlorine into the entire water system. You must pour a calculated amount of unscented household bleach into the well casing and circulate the water until you smell chlorine at every tap. After letting the solution sit for 12 to 24 hours, you must flush the system until the chlorine odor disappears. A common mistake is failing to bypass the water softener or carbon filter during this process, which can damage the media or trap bacteria inside the unit.

One nuance is that shock chlorination provides only a temporary fix. It kills existing bacteria but does not address the underlying cause, such as a faulty well seal or a nearby contamination source. If follow-up testing reveals bacteria again, the system requires a permanent solution like continuous chlorination or a UV light system. Relying solely on periodic shocking without fixing the structural integrity of the well often leads to recurring contamination.

Are there specific groups of people, such as those with open wounds or compromised immune systems, who are at higher risk?

Yes, individuals with open wounds, surgical incisions, or weakened immune systems face a significantly higher risk of infection. For these people, even a low concentration of bacteria, such as 1 colony-forming unit per 100 milliliters, can lead to serious complications or systemic illness that would not affect healthy adults.

How can homeowners effectively test their water for the presence of total coliform and E. coli?

Homeowners should collect water samples in sterile containers and submit them to a state-certified laboratory for analysis to ensure accuracy. Using a professional lab is the only way to obtain reliable, legally defensible results for your water quality.

Compare your lab results against the local health department’s maximum contaminant levels to determine if your water meets safety standards.