Your water storage tank is an essential part of your water system which needs to be regularly maintained because neglected water tanks and systems are high-risk areas for the proliferation of bacteria such as Legionella, E coli, Pseudomonas and TVC.

When water systems are allowed to deteriorate, neglected tanks and cooling towers can harbour bacteria which thrive in stagnant conditions, feeding on dirt, scale, rust and debris. That’s why water tank cleaning is an important part of our armoury in the fight for safe water.

So what should you do to ensure you water tank is clean and fit for use? To prevent or control these risks, precautions should be taken to keep the system and water clean.

1. Conduct a thorough risk assessment

A thorough risk assessment will survey your water tank and highlight any problems. The report will recommend any remedial actions required. For example, the risk assessment will identify whether legionella growth is present in your system. Legionella will grow where water is allowed to stand unused and is warmed to above 20C.

L8, the Approved Code of Practice & Guidance for the Control of Legionella bacteria in water systems, requires water storage tanks to be inspected.

2. Water tank cleaning and repair

Once inspection has taken place, if necessary, water storage tanks should be physically cleaned and then disinfected. Corrosion and scale formation in a water tank if left untreated weakens the structure of a tank and can also harbour bacterial growth. Old tanks can be drained, dismantled and removed and new tanks fitted.

Existing systems should be drained and cleaned. Physical cleaning is carried out by disinfecting, scrubbing, and pressure washing of all tank surfaces. This strips off layers of bio-film known to harbour the Legionella bacteria.

This is then followed by the chlorination of water tanks and pipework, which is effective at removing bacteria and viruses. It is the most inexpensive method of disinfection, saving you money.

3. Regular testing and servicing

Water samples should be taken and analysed annually, or as defined during the risk assessment. This is particularly important for high risk water sources, such as stagnant water in water storage tanks.

The process of water testing requires adhering to a series of procedures in order to minimise the risk of the water sample being altered before undergoing the water testing.

If you followed these steps, you can rest assured that your maintenance standards are being met and that you have a clear audit trail in the event of an inspection. Tenants, staff and building users can also have peace of mind that all reasonable precautions are being taken to manage your responsibilities.

Brodex provide these services to a wide range of sectors including– healthcare, hospitality, social care, public and government buildings, manufacturing and industry, education, property and retail.