Lead water pipes found at Bryn Garth estate, Denbigh
More than 100 homes on a Denbighshire estate will be tested to see if they have lead supply pipes.
It comes after some properties on the Bryn Garth estate, Denbigh, were found to have lead water pipes to their homes.
The use of the pipes was banned in 1970 after it was identified as a potential health risk, particularly to children.
Denbighshire council said it was working with Welsh Water to see how many properties had been affected.
One local councillor said traces of lead were found at two properties on the estate following random tests.
In a statement, Dwr Cymru Welsh Water said: "During a recent routine check on supplies at Bryn Garth Estate in Denbigh, we identified that some properties have lead water pipes feeding their properties.
"The pipes, known as supply pipes, do not form part of our network and are the responsibility of the customers.
"Letters have been sent to residents to advise them we will be carrying out a survey to help them identify if they have lead supply pipes.
"Once this has been carried out, we will explain to the customers the options available to them should they wish to have the pipes replaced. Replacing the pipes will be the responsibility of the property owner."
A spokesperson for Denbighshire council said: "Denbighshire County Council is working with Welsh Water to understand how many properties have been affected and the extent of lead levels within the water supply.
"Once the testing has been completed we will work with Welsh Water and the residents to ensure any necessary works are undertaken."
According to the Drinking Water Inspectorate, lead can build up in the human body, with infants and children at particular risk "because lead can have an adverse impact on mental development".