Irish Water is investigating after reports of a strange smell and taste to drinking supplies in parts of Dublin.
Members of the public have reported issues in the likes of Inchicore, Marino and Castleknock.
The company says it can indicate a change in the treatment processes e.g. more chlorine being added.
Or it can be down to the impact of weather on a water source or the presence of organic matter or minerals that have been picked up as the water flows through the network.
It says some people may be more sensitive to changes in how their drinking water tastes or smells. However it's reassured the public the water is safe to drink;
"Irish Water can confirm that drinking water produced at our water treatment plants serving Dublin is compliant with drinking water regulations and is safe to drink. "
Irish Water says anyone with concerns can get in touch with the company through it's customer contact centre which operates 24/7 on 1850 278 278.
Call for reassurance
The utility has been called on to make a public statement.
Sinn Féin councillor Daithí Doolan says people need more reassurance;
"This is deeply concerning for people, particularly at a time when people are concerned with their health and safety with Covid and I think people were concerned was the water drinkable or not because it was discoloured and there was a bad taste of mud and earthy taste, that's what residents were complaining to me about."