Water Tank Chlorination

Domestic water tanks should be inspected regularly and cleaned when deemed necessary. It is also a key component in adhering to the HSG274 and ACoP L8 guidelines.

Why domestic water tank cleaning is essential

The risks

Stagnant, low circulation water sources can be a potential breeding ground for unwanted and harmful bacteria. Stagnation can be caused by a number of factors including under-utilising water, using an excessively large tank, and issues in your water system causing blockages or poor flow. These factors aside, there will always be some stagnation in water tanks, therefore, regular cleaning and disinfection is essential even if these risks are low.

Regular cleaning and disinfection is essential because stagnant, low circulation of water sources can be a potential breeding ground for unwanted and harmful bacteria, even if these risks are low. Some stagnation will always be present and can be caused by conditions such as, under-utilising water, using an excessively large tank, and issues in your water system causing blockages or poor flow. 

Cold water storage tanks are also a common source of nutrients for biofilm and bacteria, including Legionella. Over time a dirty tank can develop rust, sediment, and silt; unchecked tanks can even become contaminated with organic matter such as leaves and in extreme cases small animals.
Water storage tanks present a particular risk of contamination and should be subject to regular checks. Nutrients present in water tanks can allow biofilm and bacteria to survive, grow and reproduce, including legionella. Dirty tanks over a period of time can develop rust, sediment and silt, and also can be contaminated with leaves and even small animals in extreme cases.
Guidelines and codes of practice

The Health and Safety Executive's HSG274 guidelines and code of practice (ACOP L8) state that tanks should be inspected at least once a year, or more often if contamination is found.

Domestic water tank cleaning procedure

The following procedure is designed to comply with the requirements of BS8558:2015 ‘Guide to the design, installation, testing and maintenance services supplying water for domestic use within buildings and their curtilage

Cleaning and disinfection of water storage tanks is one of the key factors to ensuring there is a clean water supply to the outlets it serves. Without regular cleaning, a build up of dirt and sediment can be present in the tank.

Numerous types of bacteria can be present in water, including the potentially fatal legionella. Neglected tanks are extremely high-risk areas for the spread of disease, as legionella bacteria can proliferate where conditions in water systems are allowed to deteriorate.
Without regular cleaning, an accumulation of dirt and sediment and numerous types of bacteria can be present in the water tank, including the potentially fatal legionella. Neglected tanks are extremely high-risk areas for the spread of disease, as legionella bacteria can proliferate where conditions in water systems are allowed to deteriorate.

Cleaning and disinfection of water storage tanks is one of the key factors to ensure there is a clean water supply to the outlets it serves. SP Environmental Services Ltd undertake cleaning and disinfection of water tanks in strict accordance to PD855468. On completion of the work a certificate is issued as well as a full report, including pictures of the water tank condition before and after cleaning.

SPES are registered with the Legionella Control Association & use the very latest methods of disinfection techniques & modern disinfection chemicals to ensure a superior level of hygiene, stripping of layers of bio-film known to harbour the legionella bacteria, whilst being safer, environmentally-friendly and better value for money.