AN illegal toilet fitting could turn your water bright blue and render it undrinkable.

Severn Trent Water has urged customers to check whether their toilets feature an illegal inlet valve.

When the valve is combined with a blue toilet block it can result in the blue toilet water being siphoned back to the kitchen tap after a loss of supply.

Dan Littlewood, water fittings senior technician at Severn Trent, said: “Essentially, the incorrectly installed valves are submerged in water in toilet cisterns and won’t cause a problem unless there happens to be a loss of supply.

“Once that happens, the valve effectively ‘sucks’ the water all the way back to the kitchen tap and our customers end up with bright blue water that, for obvious reasons, they shouldn’t drink.

“We’d urge everyone to take a look at their cistern and to make sure that everything’s nice and legal and, if it’s not, then fitting a Water Regulations Advisory Scheme (WRAS) valve as per it’s installation requirement note can prevent contamination.”

Advice from Severn Trent is to only use WRAS products in accordance with their installation requirement notes.

He added: “From our point of view, it’s bad enough that our customers have had a loss of supply. We really don’t want them to have to deal with blue water as well when it’s relatively easy to make sure that it’s never an issue.”

In order to check your valve, go to www.wras.co.uk. Severn Trent is happy to advise anyone in doubt if they email water.regulations@severntrent.co.uk