Skip to content


What is Legionella?

Legionella is a type of bacteria which can enter your water supply. The bacteria in water systems can grow when water is stored between the temperatures of 20°C and 45°C where there is limescale, or other debris, which the bacteria can feed on. There is a low risk of legionella being in your home water supply. This is because most properties do not have complex water systems, do not store a large amount of water, and the water is used often. Despite the lower risk, it is still important that control measures are in place. This can be done by:

  •           keeping the hot water supply hot;
  •           keeping the cold water supply cold;
  •           keeping good circulation of water.

When legionella bacteria enter a water supply, it may cause illnesses such as Pontiac Fever or Legionnaires Disease. These have flu-like symptoms and, in more serious cases, pneumonia. Although rare, it can be fatal. These illnesses are not contagious. These illnesses cannot be contracted by drinking water contaminated by the legionella bacteria; they are contracted as a result of inhaling contaminated water droplets. Those most at risk from falling ill due to legionella bacteria are:

  •          people over 45 years of age;
  •           people who smoke;
  •           people suffering from chronic respiratory or kidney disease;
  •           people with diabetes, lung or heart disease;
  •           anyone who is immunocompromised.

The Council's responsibilities

We complete Water Hygiene risk assessments on all water systems that may be considered more complex. For example flats where there are centralised water storage tanks and heating systems, such as our Independent Living Sites. These assessments highlight any areas where we need to intervene, such as identifying unused pipework which may cause water to stagnate.

Our Site Officers also complete regular water temperature monitoring. They check the temperature of stored water, and check the tap water temperature. This is to make sure that the water is reaching your property at the right temperature. Additionally, our specialist contractors will clean and disinfect communal water tanks and service valves ever year. This is to ensure that systems are clean, descaled and any built up sediment is purged. Some water outlets that are not frequently used, such as taps or communal toilets, will be flushed weekly by the Site Officers. This is a simple process where the water is turned on for a few minutes to purge any potential stagnant water from the pipes.

Tenant responsibilities

Make sure that the thermostat of your hot water tank is set to at least 60°C. This temperature kills legionella bacteria, and is the temperature set by our heating contractors during their annual visit. Please do not change this temperature and do not turn off your cylinders. Keep all shower heads and taps clean and free from limescale which can be a nutrient for bacteria to feed on. As a guide, shower head cleaning should be completed at least once every 3 months. Take care if using home hot tubs. The water within these is kept at an ideal temperature for bacteria to grow and multiply. If you do use one, please follow the manufacturer’s guidelines for maintenance, cleaning, and disinfection, as well as regularly draining down when not in use.

If you leave your home for more than a week, run all your taps for a few minutes when you return. You should also run taps that are not in regular use on a weekly basis. To safely flush a shower head, place it down on the shower or bath floor to avoid releasing water droplets into the air. Toilets should also be flushed with the lid down following a period of low or non-use. Run garden taps weekly and drain hosepipes of water after use. Also avoid storing them in direct sunlight. Do not use water butts with a hosepipe, and ensure that they are kept clean and drained down regularly.

If you have concerns about your water system, or you think something isn’t quite right, please get in touch with us. Please let us know immediately if any of the following occur:

  •           Cold water runs warm after pipework has been flushed;
  •           Your boiler or hot water cylinder is not working properly, particularly if the water is not coming out of the taps at a lower temperature than usual;
  •           Your water is discoloured.
Last reviewed: