How To Clean Water Butts

Introduction

Step By Step Video

YouTube Video

Hello Two!

Hello Three!

Why Clean Water Butts?

Whilst rainwater is pretty clean when fresh, there are risks when storing rainwater, both for plants and gardeners. Rainwater can be contaminated with bird droppings, pollutants, and if left unused, can be a breeding ground for bacteria, fungi, and algae, as well as developing an unpleasant smell. Indeed, there has been research showing that many, perhaps the large majority of garden water butts, contain legionella bacteria, that can lead to a fatal form of pneumonia.

Now, I’m not a water scientist or health expert, so please take your own decisions about whether to use water butts, and how to minimise the health risks when using them, and any government or health advice that may be released in the future.

The purpose of this page is simply to show what I do to minimise the risks, whilst collecting water and using it around my allotment. I clean my water butts once a year, to help avoid the build up of bacteria and algae in water butts. I have used water butts to store rainwater collected from my house roof and shed roof at home, but now I’ve located all my water butts at my allotment to provide a watering system for my polytunnel.

Risks Of Storing Water In Water Butts

I think it’s helpful to start with the conditions that make water stored in water butts potentially unhealthy. To avoid legionnaire bacteria, it is recommended to keep water cold, which means below 20 °C, or hot, above 60 °C. Unfortunately, summer weather in the UK provides the best conditions for the harmful bacteria. And this is only legionnaire bacteria, there are other harmful bacteria and fungi too.

Therefore, I think it’s best to consider all water stored in water butts as a potential health risk, and take appropriate precautions. What appears to be particularly risky is storing water for prolonged periods, as this allows time for bacteria to multiply, and activities that lead to the diseases becoming airborne.

For a gardener, this is especially the case when spraying water. So, spraying water from an outside tap supplied by mains water is okay, but using a pump to spray water stored in a water butt is much more risky. Also, using the water indoors with poor ventilation is higher risk than using outdoors on a clear day.

By comparison, a lower risk activity is taking water out of a water butt by watering can, as this reduces the amount of bacteria becoming airborne. To further reduce the risk, it’s best not to lean over the watering can as it is being filled.

During the summer months, the drip irrigation system I use in my polytunnel, means that the water is constantly changed as the butts are emptied and filled. This is helpful, but even during this period, the water butts are never fully empty, and therefore harmful bacteria can persist.

In addition, overwinter, I like to leave a few inches of water in each water butt to make them heavy enough not to be blown away when stormy weather arrives. Although the weather is cold, the stored water may contain dormant bacteria which may begin to multiply when warmer spring temperatures arrive.

To sum up, my thinking is to treat my water butts as a potential health risk that needs to be managed. I manage this risk in the following ways:

• By a thorough clean once a year
• By regularly using the water to prevent the build up of bacteria
• And by taking preventative measures when using the water to reduce risk, especially the risk of breathing in unhealthy bacteria

How To Clean Water Butts

I think the best time of year to clean my water butts is the spring, when the weather starts to warm. At this time of year, I don’t need my water butts to water my plants, both because they are small, and also because there is plenty of rain around. Alternatively, a warm autumn day would work well.

The first part of cleaning my water butts is to fully empty them. All my water butts are fitted with a tap at their base, therefore emptying them is simply a case of opening the taps. As I mentioned earlier, the risk to a gardener is when diseases in the water butts become airborne. Therefore, I open the taps when I will be working away from the water butts. I often do this just before I walk home. This allows the water to empty away without me being there to breath in the air around them.

Later that day, or the next day, I’ll return to tip the remaining water out of the water butts. If it’s a warm day, I’ll leave the water butts out to dry for a little while, turned upside for better stability, and to allow the water to drain away.

To clean the water butts, I use the following:

Hydrogen Peroxide

I use hydrogen peroxide as a disinfectant, and dilute this in water as per the instructions on the container. Hydrogen peroxide naturally breaks down to water and oxygen, and when diluted properly, is effectively a mild bleach that is safe for the environment when used in small amounts.

I use 3% hydrogen peroxide, sometimes called medical grade hydrogen peroxide, and I’ll mix this in equal quantities with water before using.

Personal Protective Equipment

• I put on rubber gloves to protect my hands
• A face mask to help stop me breathing in any harmful airborne particles,
• Goggles to protect my eyes from splashes

Cleaning Equipment

For the cleaning equipment, I have:

• A large sponge
• A bucket
• A mop

Having a long handle helps to clean inside the water butt without having to reach inside and breathe the fumes.

Using the sponge, mop and bucket, I’ll then clean all the surfaces inside the water butts until they are clean. Any muck or algae on the surfaces of the water butts should easily wipe away.

I like to use a watering can to rinse away any residues of the cleaning solution, and then leave the water butts to dry in the sun. Once dry, I’ll fill the water butts with enough water to cover the level of the taps. I do this to provide weight to stop them being blown over on a windy day.

More Ideas To Keep Water Butts Clean

I like to use my water butts to store rainwater, and nothing else. Here are some more ways of keeping water butt water cleaner between their annual wash:

Stop Organic Debris Falling Into Water Butts.

Any organic debris inside a water butt can rot. As it breaks down, it can release smelly odours. A well fitted lid is the best solution, as well as positioning the water butts away from trees to prevent leaves being blown inside.

Keep Gutters Clean Of Moss & Debris

It is common for moss to fall into gutters. If a water butt collects water from these, eventually this material will fall into the water butt. Keeping these clear of organic debris will also mean more water arrives inside a water butt.

Keep Water Butts In The Shade

Bacteria multiply faster in warmer water. By keeping water butts in the shade, it should slow down the build up of disease.

Keep Using The Water

When water is used, any diseases it contains will be washed away with it, effectively keeping the overall level of disease much lower than water left to stagnate.

In addition, there are solutions that can be bought, which are designed to be added to water butts already full with water to help treat it and to prevent water butt odours. I haven’t used these myself, but they are another option to consider in between their annual clean.

How To Reduce Risk When Using Water Butt Stored Water

And, as I mentioned earlier, the following techniques can help reduce exposure to diseases that may be found in water stored in water butts:

• Avoid spraying water from water butts
• Use water butt water outdoors
• Avoid leaning over watering cans when filling them up
• Wear gardening gloves and a mask when watering