What does the tank cleaning process entail?

The water tank cleaning process varies depending on the size, type and complexity of the tank and water system. A full risk assessment is carried out first, followed by draining the tank and removing contaminants. The tank is cleaned using modern disinfection methods, including scraping, sand blasting and wire brushing if needed, and then disinfected, often with Silver Stabilised Hydrogen Peroxide. Disruption is kept to a minimum, and full documentation is provided upon completion.

How do I know if my water tank needs cleaning?

Water tanks require cleaning when certain conditions occur, such as installation of a new system, refurbishment, installation of new components, long periods of inactivity, visible contamination, significant system alterations, microbial contamination detected in samples, or if a Legionnaires' disease outbreak is linked to the system. A risk assessment may also indicate the need for cleaning. Maintaining correct pH levels is essential to inhibit Legionella growth. L8 ACOP provides legal guidance on contamination levels and required corrective action.

How long does it take to clean a water tank?

The duration of water tank cleaning depends on the tank's size, level of contamination and accessibility. On average it takes three to five hours. A more accurate estimate can be provided after inspection.

How often should commercial water tanks and cold-water storage tanks be cleaned?

Water tanks should be cleaned based on the findings of an annual inspection. Most tanks require cleaning every two to three years, depending on sediment build-up. Potable water tanks should be cleaned and disinfected annually. Factors such as damaged insulation, faulty vermin screens or oversized tanks can increase contamination or stagnation risk.

What chemicals are used to clean water tanks?

Swiftclean uses Stabilised Silver Hydrogen Peroxide, a highly effective oxidising disinfectant used for Legionella control. It kills bacteria, viruses, fungi, algae and amoebae. The silver compound provides long-lasting protection. It is chlorine and alcohol-free, non-corrosive, removes biofilm and breaks down into harmless water and oxygen. Its effectiveness is unaffected by high temperatures or pH, and the dosed water remains safe to drink when used as instructed.

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Water Tank Cleaning

At Swiftclean we provide professional, reliable and cost effective water tank cleaning services for every commercial property, from small tanks up to large, complex systems.

Clean, Safe Water Tanks

Providing professional, reliable and cost-effective water tank cleaning services for commercial properties. for everything from small domestic tanks up to large, complex commercial systems.

At Swiftclean, we don’t just clean water tanks; we help protect the health of everyone using the water supply. Our fully trained engineers follow strict water hygiene protocols, in line with HSE ACoP L8 , ensuring every tank is free from harmful bacteria and compliant with UK regulations.

We know just how important maintaining a clean water tank is to not only those in charge of the building, but for the health, safety and wellbeing of those who visit, work or reside within it. A neglected tank can quickly become a health hazard. Over time, even clear water can hide unseen dangers such as biofilm or bacterial growth. That’s why tank hygiene should be a preventative priority, not just a reaction to problems.

We help clients put in place a maintenance schedule that ensures their tanks are checked, cleaned, and tested at regular intervals to prevent bacterial growth, extend the lifespan of the system, and maintain compliance with current water hygiene regulations.

Whether you are a facilities manager responsible for a commercial premises, or part of a housing association, our goal is the same: to provide clean, safe water every single time you turn on the tap.

Cold Water Storage Tanks

Cold water storage tanks are used to store a large amount of water that is then used to supply the building, and the tank is then replenished at a steady rate from the mains water supply. They can be used to store water for hot and cold taps as well as drinking water, car washing, factory production, toilet flushing, water heating systems and various other applications.

These types of tanks can commonly be found in a wide range of properties, including:

Houses
Residential homes
Offices
Schools
Hospitals
Commercial buildings
Factories
Industrial properties
Leisure centres

To ensure the continued safety, efficiency, and compliance of your water supply, cold water storage tanks should be properly maintained through a combination of protective measures, regular inspections, and professional cleaning in accordance with recognised standards.

In order to keep stored water clean, safe, and free from harmful contaminants, every cold-water storage tank should meet the following key maintenance standards:

Fitted with secure lids to prevent contamination from insects or debris
Kept in a clean, ventilated area to avoid excessive heat build-up
Inspected regularly for cracks, leaks, or corrosion
Cleaned and disinfected in line with HSE guidance

With the help of Swiftclean’s professional inspection and cleaning services, you can safeguard water quality, avoid costly repairs, and ensure full compliance with water hygiene regulations.

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Swiftclean Commitment:

FREE quotation/technical advice – Nationwide – call 0800 243 471
Works carried out in accordance with the Legionella Control Association (LCA) code of conduct
Risk Assessments and control schemes carried out to L8, BSRIA and CIBSE guidelines
All works fully certified and legionella control logbooks provided
Fully trained and directly employed staff
Method Statements and Risk Assessments provided site specific as required
Training for your own staff following risk assessment

CHECK YOUR COMPLIANCE

Why Is Water Tank Cleaning Important?

Over time, water tanks can become contaminated with dust, dirt, sediment, debris, mould, rust, corrosion, sludge, biofilm and numerous types of bacteria including the potentially lethal Legionella. This deadly bacteria can thrive in water tanks under the right conditions and could lead to an outbreak of Legionnaires’ Disease which is extremely dangerous for people’s health with recovery sometimes taking a year or in some cases proving fatal.

This bacterium thrives in stagnant or lukewarm water, typically between 20-45°C, making poorly maintained tanks the perfect breeding ground. Once present, they can be spread through aerosols such as showers or taps and cause an outbreak of Legionnaires’ Disease, which is extremely dangerous for people’s health and in some cases can prove fatal.

In addition to health risks, a dirty water tank can also cause:

Reduced water flow due to sediment build-up
Unpleasant odours or tastes in tap water
Staining or discolouration in sinks, baths, and appliances
Premature wear to plumbing fixtures and systems

It is important to conduct regular inspections of your water tanks to help determine if they are clean, safe and free of harmful contaminants and bacteria like Legionella.

Professional water tank cleaning is an essential part of Legionella control and water hygiene that helps to remove impurities, dirt, debris and bacteria to ensure that the tank is clean, safe and compliant.

Water Tank Cleaning Guidance

Regular cleaning is essential to maintain safe water quality. In most cases, tanks should be inspected annually and cleaned whenever contamination is detected. However, high-risk environments such as hospitals, care homes, or facilities for vulnerable individuals may require more frequent cleaning, sometimes every six months, to remain compliant with HSE ACoP L8 guidance.

The safest and most effective cleaning method involves draining the tank, removing sediment and debris, mechanical and/or hand scrubbing all internal surfaces, and disinfecting with an approved biocide before rinsing and refilling with fresh water. This process is followed by water sampling to confirm it meets safety standards.

Because of the confined spaces, chemical handling, and potential exposure to harmful bacteria, water tank cleaning is not a task for untrained individuals. By using a specialist service like Swiftclean, you ensure not only a thorough clean but also full compliance documentation for your records, giving complete peace of mind.

Professional Water Tank Cleaning

At Swiftclean, our domestic and commercial water tank cleaning services provide our customers with the peace of mind in knowing that their water systems are safe, clean and carefully monitored to ensure that they are compliant and adhering to legal requirements.

Our engineers are trained in confined space entry, safe chemical handling, and advanced disinfection methods. We use stabilised hydrogen peroxide, mechanical and/or hand scrubbing, and vacuum removal of sediment to ensure a deep clean. For tanks in sensitive environments such as hospitals or schools, we offer tailored cleaning plans to minimise downtime and disruption.

We also provide detailed post clean reports including photographic evidence, water sampling results, and recommendations for ongoing maintenance. This documentation can be vital for demonstrating compliance during health and safety inspections.

If you have any questions or would like to know more about our water tank cleaning services, then do not hesitate to get in touch and one of our advisors will be happy to help. Alternatively, fill out our contact us form, for a no obligation water tank cleaning quote.

Swiftclean Water Tank Cleaning Services

Swiftclean provides commercial water tank cleaning to buildings of all demands such as factories, offices, leisure centres and managed properties. In buildings with people likely to be at higher risk of legionnaires disease such as care homes, it is even more vital to have regular water tanks checked and cleaning.

The expertise that Swiftclean have gained as a specialist in the hygienic control for building services plant ensures that the water systems will comply with the latest Health and Safety Guidelines and will avoid any violation of current regulations. Our experience and knowledge ensures our commercial tank cleaning is thorough and that cleaning and disinfection is done thoroughly and safely to prevent contamination.

Registered with the Legionella Control Association, Swiftclean use the very latest methods of disinfection techniques and modern disinfection chemicals for our commercial tank cleaning services 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. On completion of every contract a certificate of completion is issued for your monitoring records and to provide for inspection.

L8 the Approved Code of Practice & Guidance for the Control of Legionella bacteria in water systems and requires water storage tanks to be inspected annually. It is written and published by the Health and Safety Executive and outlines the responsibilities of duty holders and the frequency and level of monitoring that needs to be carried out to prevent legionella. Find out more about Legionella control.

Once a water storage system has received a Swiftclean refurbishment the tanks should be examined annually to comply with regulations, then where necessary cleaned and disinfected. It is a much more cost effective operation to service a tank that has already been brought to pristine condition. On completion of every contract a certificate of completion will be issued.

Water Tank Refurbishment

Swiftclean will undertake cleaning and refurbishment of all manner of water systems and associated pipe work, from a 50 litre domestic tank to a massive man-made reservoir.