Consider The Risks Of Water Systems Before Reopening Buildings, says WRAS

• Content
• Safety & Health
• Consider The Risks Of Water Systems Before Reopening Buildings, says WRAS

21 May 2020 | Updated 26 May 2020

The Water Regulations Advisory Scheme (WRAS) is encouraging business and property owners to consider the risks posed by their water systems sooner rather than later, to avoid health risks.

The restrictions placed on people and businesses to restrict the spread of COVID-19 since mid-March have meant many premises have been left closed or with minimal staff, meaning many water systems may have been left stagnant.

This could have resulted in warming of water in internal plumbing systems, growth of micro-organisms or increased uptake of plumbing metals. Stagnant water can encourage the growth of micro-organisms, including Legionella.

Plumbers, facilities managers and landlords are therefore urged to follow Water UK guidance, as stagnant water can pose a potential health risk.

“Stagnant water can pose a risk for the users and residents of any kind of building, so it is vital that the water system is prepared and refreshed before access resumes.”

–Julie Spinks

Managing Director, WRAS

Water UK guidance

Where buildings have been unoccupied for less than 30 days or where steps have been taken to prevent microbiological growth, the guidance advises those property owners should undertake the following:

• Ensure that the water in the plumbing systems is fresh, run all taps individually, starting with the tap nearest to where the water enters the building and moving systematically to the most distant outlet It should be sufficient to run until the water is clear and feels cool to the touch
•  Where water is supplied from storage, storage cisterns should be emptied and re-filled with water direct from the incoming supply, before the taps are flushed
• Flushing should be carried out in a manner which minimises aerosol generation, e.g. removing shower heads prior to flushing, to reduce the risks of Legionella transmission
• Safety considerations should be made for those flushing including appropriate PPE
•  Ensure that all appliances are also thoroughly flushed through before use, using the manufacturer’s instruction manual
•  If the property has any internal filters or water softeners, these should be checked to ensure they are working correctly as outlined in the manufacturer’s instruction manual
•   Ensure that if plumbers are required to make any changes or repairs to the plumbing system that approved plumbers under the WaterSafe scheme are used

Advice for larger buildings

For larger buildings, those with tanks, showers, calorifiers and more complex pipework, Water UK explains that the expectation is likely to be for more extensive flushing followed by cleaning and disinfection. Buildings with a complex plumbing system should ensure they have a competent person to oversee this work.

Where the building has been unoccupied for more than 30 days it is important to refer to your buildings water management plan and your water advisors as flushing, disinfection and other measures may be required.

Julie Spinks, Managing Director of WRAS, said: “Whilst businesses are understandably keen to open their doors, it’s important to consider all areas of health and safety, beyond those directly related to COVID-19.

“Stagnant water can pose a risk for the users and residents of any kind of building, so it is vital that the water system is prepared and refreshed before access resumes.

“Water UK’s guidance on recovering buildings and networks after prolonged inactivity provides clear and helpful information for anyone involved in managing a premises, but approved plumbers should also take the time to understand the recommendations to advise their clients accordingly.”

“Locked down buildings need more than flushing to ensure water quality” 

Toby Hunt from Guardian Water Treatment, urges responsible parties to proceed with caution when it comes to flushing, and says that it is not a standalone solution:

"Our evidence shows that flushing buildings during periods of inactivity alone may not resolve potential water quality issues. While it could serve to reduce Legionella bacteria, overall microbiological control is likely to be compromised," said Hunt.

"We have compared four weeks of sample results from this period last year and now, in London buildings that have been locked down and flushed regularly. Legionella failure results are virtually the same, but the TVC (Total Viable Count - which gives an estimate of the total concentration of microorganisms) failure rates have almost doubled.

"Nearly half of the buildings sampled in the last four weeks have failed TVC results, compared with 24% in the same period last year. As the weather gets warmer, these failure rates are likely to increase.

"Flushing is still important however other measures may be required to ensure control of bacteria in these water systems. We recommend that supplementary microbiological samples should be taken to prove regimes are effective, other actions implemented if required."

More guidance can also be found at Legionella Control Associations’ (LCAs) website.

Picture: An image showing a whirlpool and a droplet of water

Article written by Ella Tansley | Published 21 May 2020

Share

Related Articles