Businesses must flush out water supply before reopening to avoid deadly Legionnaires’ disease risk, government says

Public Health England says dangerous bacteria may have built up during lockdown

Businesses have been warned to flush out the water supply in their building before they reopen as potentially deadly Legionella bacteria may have built up in water systems during the coronavirus lockdown.

Public Health England (PHE) said on Tuesday that dormant water systems would result in bacterial growth, particularly during periods of warm weather, which could pose a threat to the public.

Legionella bacteria is naturally present in water systems and causes Legionnaires' disease - a form of severe pneumonia which is fatal in 10 per cent of cases.

Water systems which have not been used during the UK’s lockdown pose a “potential health risk” due to the bacteria, PHE said.

Legionnaires’ disease is especially dangerous for people over 45 years of age, smokers and heavy drinkers, and those with underlying health conditions, according to the Health and Safety Executive (HSE).

HSE has said outbreaks of the bacteria will occur when water is kept at a high enough temperature (between 20C and 45C) to encourage growth.

PHE guidance issued this week said “regular flushing” of water systems was required during lockdown to prevent the growth of bacteria.

It added that all organisations with a water supply which were currently shut down would need to take action, but singled-out dental practices, hairdressers, gyms and hotels as being particularly at risk.

“Regular flushing out of the premises' water system throughout the shutdown period is required,” PHE said.

“However, all aspects of the water management system need to be reviewed before reopening the business, and necessary action will be dependent on the complexities of the system.

“This may be done by a combination of workers employed by the organisation if they have the necessary skills and knowledge.”

The guidance added that a water consultant would be needed if a system requires disinfection.

Water Hygiene Services, a Leeds-based company, warned of the risk of water stagnation leading to Legionella bacteria building up in systems last week.

Ben Baldwin, the company’s managing director, said organisations needed to start taking action now to avoid overloading engineers with work when lockdown restrictions are lifted.

“For example, should schools, colleges and universities all reopen in the coming months, there will be a huge demand for water systems to be serviced accordingly over the next few weeks and months, and possibly not enough engineers to complete this work at the last minute,” Mr Baldwin told the Yorkshire Evening Post.