Can Bacteria Grow in Water Coolers?

Did you know that failure to clean your water cooler regularly could be the reason why you recently got sick? A dirty water dispenser is a home to mold, bacteria, and disease-causing germs.

If you don’t clean your water cooler, you might not know what’s lurking in there. Even if filtered and bottled water might be contaminant-free, it can get contaminated in a dirty cooler.

So, can bacteria grow in the water coolers? The answer is a big YES! Bacteria grow quickly in places where there’s a high level of moisture.

Water cooler maintenance is very vital for your health.

In this post, we look at contaminants that could be in your water cooler. Keep reading

Common Contaminants in Water Coolers


Heterotrophs are microorganisms that feed in organic carbon, including yeast, mold, and bacteria. You might be wondering how bacteria end up in the water when the water itself isn’t a food source, right?

Well, bacteria are incredibly resourceful when it comes to using materials as food. For example, once inside your water cooler, certain types of bacteria like Pseudomonas Aeruginosa feed on components found on seals and rubbers within your dispenser.

Heterotrophs can also enter the water cooler when you change the water bottle. Remember, every time you change the water bottle, you expose the surface to the air, which is full of bacteria.

Contaminants can also get into your dispenser if someone touches the internal components.

Chemical Residue

Cleaning your water cooler regularly may rid your water of unsafe microorganisms. However, the cleaning supplies are likely to create problematic issues.

Most cleaning processes include chlorine and bleach. And although the products are highly effective at getting rid of bacteria from your drinking water, they are not safe for human consumption.

This means that you need to ensure that these products are thoroughly flushed through the system and that no residue is left.

Should you dispense water from your cooler and realize that it’s off-tasting or appears cloudy, rinse the dispenser further for your safety.


The only ingredients that algae need to grow are a damp environment and some sunlight. Actually, under the right circumstances, fluorescent light is enough to make it grow.

Although non-toxic, they impact the smell and flavor of the water.

Illnesses Caused by Contaminated Water Cooler Water

Contaminated water cooler water can pose a health risk to you and your coworkers. So although you might enjoy the convenience these water coolers provide, is it worth the risk?

Germs lurking in the contaminated water might even make you ill.

Species of bacteria that grow in the water can cause several illnesses. For instance, you could contract Legionnaires’ disease, which starts like flu and later progresses to pneumonia.

In the beginning, the symptoms may include aching joints, fatigue, a slight fever, and loss of appetite. This later progresses to a high fever, dry cough, shortness of breath, chills, and chest pains.

Another illness caused by bacteria is Pontiac fever, which produces flu-like symptoms. This fever usually lasts for several days.

Other than these illnesses, you can also contract common colds and viruses from the water cooler, especially if sharing it with many people per day.

The Solution

To avoid bacteria and illnesses surrounding a water cooler, you should ensure proper cleaning and use in your workplace.

Some of the basic rules for the sanitation of the water cooler include:

  • The water cooler should be cleaned every 3 to 6 months.
  • Spray the dispensing taps at least once per week with the appropriate sanitizing agent.
  • Avoid filling water bottles from the tap or any other source.
  • Clean the outside areas of the dispenser and the drip tray regularly.
  • Have your water cooler filters replaced every 6 months.
  • Check the machine regularly to ensure that it’s functioning properly.
  • Only trained should help with the sanitation and maintenance of the water cooler.

It is also advisable that you get a sanitation kit from your supplier as these come with all the essentials to help you maintain the water cooler properly.


Can you get sick from a water cooler?

Yes, you can get sick by drinking contaminated water from a water cooler with disease-causing bacteria.

Do water dispensers grow bacteria?

Yes, some bacteria feed on rubber and seals on the water dispenser, grow and multiply.

Do water coolers get dirty?

Yes, water coolers get dirty and thus require to be sanitized and cleaned occasionally.

Does mold grow in water coolers?

Mold grows well in areas that are warm, damp, and with poor air circulation. This makes water coolers a perfect breeding ground for it.

How do you sanitize a water cooler?

Using a clean cloth and a solution of household bleach in water, wipe the bottle collar (thoroughly), the inside of the reservoir, the spigot, the top of the dispenser, and the grill and outside surfaces of the drip tray.

Can you clean a water cooler with vinegar?

You can clean a water cooler with vinegar solution.

How often should you clean the water cooler?

You should clean your water cooler with every bottle change or after every 6 weeks, whichever comes first.

Is algae in a water cooler harmful?

Algae is not harmful but can alter the flavor and smell of your water.

Is mold from my water cooler harmful?

Yes, drinking moldy water can make you sick. Mold can cause respiratory problems, nausea, cramping, and unexplained infections.

What is the green stuff in my water cooler?

The green stuff is algae. It grows in water coolers that have been left alone (usually in heat) for long.


Although water coolers are highly convenient and come in handy both at home and workplaces, they need to be well maintained to prevent diseases. You need to be aware of the hazards involved with a dirty water cooler to keep safe.

And where you find that it’s quite difficult to keep the water cooler clean because you share it with so many people during the day, you can opt for a bottleless solution with a built-in filter.

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