The Commission for Energy Regulation has said it will issue a decision on water charges in August.
The Joint Oireachtas Environment Committee has heard a presentation from the Commission for Energy Regulation and Irish Water.
The committee heard that Irish Water will make an interim price control submission to CER in a few weeks' time.
Earlier, Irish Water Managing Director John Tierney said the company is committed to eliminating boil water notices in 12 months.
Currently, 19,000 people have to boil their water, most of whom are based in Roscommon.
The current delivery of water services does not meet the needs of a modern economy, he said.
He added that the majority of waste water treatment plants around the country are in breach of the EU Water Framework Directive.
The committee heard that the water services investment programme would have cost €6bn to implement with the overall requirement to upgrade services estimated at €10bn.
Mr Tierney said that since 2009, €1.5bn has been spent on water services infrastructure.
He also said that local authority staff are critical to delivering services and continuity of supply to customers.
Energy Regulator Paul McGowan has said consumers will know by August the final cost of water charges.
Responding to questions from Labour TD Kevin Humphries, Mr McGowan said they will get a cost submission at the end of February from Irish Water which they will publish in June for consultation.
The consultation period will be around four weeks.
Consumers will get an indication of prices in June and a final decision in August.
Deputy Humphries asked Cathy Mannion from the Regulator if a system in the UK was being considered, where a standing order was charged, based on valuation.
She said they were not considering a link between the valuation of houses and charges.