How to restore your drinking water system
At Welsh Water, our most important responsibility is supplying 1.4m homes and businesses with safe and clean drinking water 24 hours a day, 365 days a year.
During the COVID-19 pandemic, we’ve been doing everything we can to maintain people’s water supply and protect our customers, by delivering over 900 million litres of clean water every day.
As part of our role, we carry out 300,000 water tests every year and work with customers to ensure it’s of a high quality. The UK Government social restrictions placed on businesses and other organisations since 23rd March has seen many buildings and sites close for a prolonged period. In turn, this impacts water quality, as many drinking water systems (including water storage tanks and pipes) within buildings will have been left standing during the lockdown.
This can adversely affect the quality of drinking water and potentially risk people’s health. So, it’s important that certain steps are taken before the building is reoccupied.
Our helpful tips and Q&As below should help guide you through the process.
Frequently Asked Questions
Standing water is any water which has been held in your pipes or storage tanks for longer than 24 hours.
Standing water can result in:
- The water in internal plumbing systems becoming warmer
- Microbiological growth (such as bacteria) in the water
- An increase in plumbing metals seeping into the water
While this could simply cause your water to taste, look or smell slightly different to normal, it can also lead to potentially harmful levels of bacteria in your water, so it’s important to follow our steps to ensure your water is safe to drink.
This advice should be followed by anyone who is in charge of re-occupying a building or site that has been closed as a result of Covid-19, such as building owners, landlords, managers and operators of Refill schemes.
You can recommission your drinking water system by following these steps:
- If your water is supplied from storage, empty and refill your storage cisterns with water direct from the incoming supply, before the taps are flushed.
- Run all the taps in your building or site individually (also known as flushing), starting with the tap nearest to where the water enters the building and moving systematically to the ones furthest away, until the water is clear and feels cool to touch.
- You need to make sure that when you carry out flushing you reduce the risk of water droplets becoming airborne so e.g. remove showerheads, slowly open taps and close the lid on toilets before the first flush. Showerheads should be disinfected before they are reconnected. Safety considerations should be made for those carrying out the flushing including providing the appropriate PPE such as a mask to prevent inhalation of water droplets.
- Make sure all your appliances are thoroughly flushed before they’re used too, being careful to follow the manufacturer’s instructions.
- If you have any internal filters or water softeners, check they’re working correctly as outlined in the manufacturer’s instructions. Consult with the manufacturer regarding the risk of microbial growth on filters or softener resins if they have been sitting unused in water for a significant period of time - you may be advised to replace.
- Think about equipment connected to the water supply outside of the building e.g. jet washers and flush them safely and in accordance with manufacturers guidance.
- For larger buildings such as those with tanks, showers, calorifiers (also known as indirect-fired water heaters) and more complex pipework, as well as following the above steps, you’ll also probably need to carry out more extensive flushing followed by cleaning and disinfection. If your plumbing system is complex, make sure you have a competent person to oversee this work. When you’re ready to recommission your water supply, make sure it’s in-line with your water safety management plan, including pressure testing all of your systems.
When the lockdown was announced, you may not have had time to carry out your normal cleaning and maintenance regime. This could lead to a build-up of waste in your drains and pipes, and your equipment to stop fat, oil and grease getting into pipes may not have been cleaned for some time.
To avoid sewer blockages that could cost you money, follow these steps:
- Clean your equipment – before you start cooking, make sure your grease management system is thoroughly cleaned in line with the manufacturer’s instructions.
- Check your drains and sink gullies – if the drains and sinks haven’t been used for some time, they could have dried up and have waste stuck in them. Check your sink gullies for any blockages and flush your drains through with water. You could also use a bio-dosing liquid or liquid fat-buster as you prepare to reopen, however, this should not take the place of a grease management system when you are operating again.
- Use sink strainers to stop waste getting into drains and pipes – this is best practice and stops waste clogging up your pipes.
- Remind your kitchen team to use bins for food waste, and to avoid putting fat, oil and grease down the drains and sinks.
Check your toilets – flush your toilets several times to ensure they are still flowing.
If you need any advice or support to help you avoid sewer blockages when reopening your business, please contact our Blockage Prevention team on 0800 085 3968 or firstname.lastname@example.org
If you’ve been regularly flushing your water system, then we’d suggest flushing your water system one more time before re-occupying your building or site.
When you have carried out the flushing of your cold water system, check that the water looks clear and normal then check the water temperature at the taps closest and furthest from the incoming mains. If they are the same temperature and the water is clear, then this is a good sign that any standing water has been flushed out.
You should think about health and safety issues for those carrying out the flushing. You should provide them with the appropriate PPE such as a mask to prevent inhalation of water droplets. You should also make sure that when they flush the system they operate taps and showers in a way that minimises water spray and droplets such as slow opening of taps, keeping the toilet lid closed and removing shower heads. Shower heads should be disinfected before they are reconnected.
To find more information on making sure your building’s drinking water is safe to drink, please visit the Water UK website here which includes a briefing note containing links to further guidance and advise from government and regulators.