Tipperary County Council is not aware if the source of the cryptosporidium that has affected Borrisokane water supply has been found, local councillors have been told.
Cllr Ger Darcy had also raised concerns as to whether the pollution could happen again.
Irish Water is installing a UV system to kill any bacteria in the supply and director of water services Jerry Robinson said that hopefully that would be done this month, but warned it was a “work in progress”.
He said the UV system should prevent issues in the future.
The issue was initially raised by Cllr Michael O’Meara.
In a statement, Irish Water has said that works to install a new disinfection system are close to completion and will be moving to the commissioning stage shortly.
"Together with our colleagues in Tipperary County Council, we have prioritised the installation of a new ultraviolet (UV) disinfection system at the treatment plant. Following the completion of this work, further consultation will take place with the HSE with a view to lifting the notice as quickly as it is safe to do so," said Duane O'Brien, Irish Water’s operations lead for Tipperary.
A total of 1,750 households are affected by the Boil Water Notice.
Separately, Nenagh MDC cathaoirleach Cllr Seamus Morris warned at Nenagh MDC that Irish Water was going to hit businesses with its Shannon pipe plan.
“In one case, it is going through a horse training track,” he said.
“We have viable businesses employing hundred of people whose live are going to be destroyed,” said Cllr Morris.
Cllr Morris said he was disappointed that the IFA,”who are supposed to represent farmers”, had not replied to his letters on the issue.
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