Double-check your outside tap

Write the name and number of a WaterSafe-approved emergency plumber on a spare Christmas gift tag and attach it to your stop tap.

We’ve partnered with the Met Office to remind you to ‘double-check’ your outside tap this summer.

Help prevent water and bacteria from contaminating your tap water supply by ensuring your outside taps have a double check valve installed. 

Sadly, many people don't realise how ill you can get if the water in your hosepipe ‘backflows’ into your drinking water, or becomes contaminated by potentially lethal bacteria, such as Legionella, that can thrive in warm, stagnant water. 

The water supply (water fittings) regulations which keep drinking water safe specify outside taps should always have a double check valve to prevent backflow.

Homes built since 1999 typically have an inline double check valve built into the supply pipe to the outside tap, and those built before that point usually have one built into the tap.

Either way, it’s essential to have protection for every outside tap, to prevent potentially harmful backflow – so we’re urging everyone to ‘double-check’.

Dos and don'ts to keep your tap water safe:

  • DON’T place hosepipes in drains, garden ponds, buckets or watering cans -contaminated fluid could be siphoned back into your drinking water supply

  • DON’T use a hosepipe which may contain warm water to fill a hot tub.  Legionella, and other bacteria, can grow quickly in warm, stagnant water and cause Legionnaires Disease if inhaled through steam or water vapour

  • DO keep your hose somewhere cool and out of the sun

  • DO turn off your hosepipe at the tap and ideally fully disconnect it and store it in a clean, dry place when not in use

  • DO fit a self-closing flow control, such as a trigger spray gun, to help use less water and reduce the risk of backflow when left unattended – but always gently run the water out of the hose without any attachments first, to avoid creating a vapour which could contain Legionella or other bacteria

  • DO fit a compliant double check valve to garden taps. The british standard (BS EN 806-5) states check valves should be replaced every ten years. All plumbing products must be compliant, such as those approved by BSI, KIWA, NSF or WRAS.

If in doubt, seek advice from a WaterSafe-approved plumber to ensure you have the right safety measures in place.

Visit the Met Office’s WeatherReady page for more weather hacks.



Our Partners

WaterSafe Approved Contractors' Scheme Operators

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