Legionella for Householders
Household water-butts may contain the common bacteria Legionella, which when inhaled in large amounts may cause an extremely rare but dangerous form of pneumonia called Legionnaires’ disease. Below is a guide on legionnaire's disease in rainwater capture systems and advice on how to combat it.
What is Legionnaires' disease?
Legionnaires' is a potentially fatal form of pneumonia, which is an inflammation of the lungs caused by bacterial infection when inhaling the legionella bacterium. Whilst this may sound terrifying, it's worth noting that Legionnaires' disease is quite rare in the UK with less than 1 cases per 100,000 population in England and Wales in 2023 (source). Those more at risk are the elderly, smokers and those with weakened immune systems. We advise care and consideration be taken as the Legionella bacterium can be found in natural water sources such as rivers and lakes but also in household water capture devices.
Symptoms
- a cough
- shortness of breath
- chest pain or discomfort, particularly when breathing or coughing
- a high temperature
- flu-like symptoms
If you experience persistent symptoms such as these then we advise you to consult with your GP or to contact NHS 111.
Risks
These factors may increase the risk of being exposed to the legionella bacterium in water capture devices.
Aeration - Legionnaires' is caught when you breathe in tiny droplets of water containing legionella. If you are using a hose or pressurised device this can increase the risk of accidental inhalation.
Organic Matter - Leaves and buildup in your guttering can end up in your water, providing organic matter and nutrients for the legionella bacterium to thrive.
Warmth - Legionella thrives in warmer temperatures and can multiply under these conditions.
Reducing risks
Watering can - Emptying your water butt into a watering-can to use in the garden rather than using a hose reduces the likelihood of inhaling water droplets.
Clean your gutters - Clearing your gutters of any debris and leaves will reduce the risk of it making its way into your rainwater capture system. If you're only going to do it once a year we would advise to do it in Autumn.
Location, Location, Location - Positioning your rainwater capture device so that it is not in direct sunlight or in it for the shortest possible time, will reduce the likelihood of the water warming and providing habitable conditions for the bacterium.
Notes
If you decide to empty out and clean your rainwater capture device, we would recommend wearing protective equipment such as a face mask and gloves to minimise the risk of contraction.
Disclaimer
The information provided in this article is intended as a general guideline for maintaining rainwater harvesting systems. While we strive to offer accurate and helpful advice, maintenance should be carried out at your own discretion. We do not assume responsibility for any issues or damages that may arise from following the guidelines provided. It is essential that you assess your individual situation and take the necessary precautions to ensure safety and effectiveness.