Irish Water says an overflow from a public sewer in Tralee has been caused by wet wipes and other debris.
The utility was responding to a statement from Cllr Pa Daly that a river through the town had been used as an open sewer.
Irish Water says a blockage was discovered and has now been cleared.
Sinn Féin county councillor Pa Daly said that there were five pipes disgorging effluent, including septic tank overflow, in a 100 yard section of the Big River in Killeen, Tralee.
He called on Irish Water and Kerry County Council to address the pollution.
Irish Water says the overflow from the public sewer was caused by a build of material such as wet wipes and other debris, which had been disturbed by the heavy rain over the weekend.
The utility is urging us not to flush inappropriate items such as wet wipes and cotton wool buds down the toilet as they can cause blockages.
It says overflows from private septic tanks are the responsibility of private owners, not Irish Water, and that property owners may apply to the utility for a connection to the public sewer network.