The warning comes as the first Irish Water bills drop through letterboxes in Donegal, Meath and Wexford this morning.

Over 1.7 million bills totalling €70m will be sent to households across the country over the next eight weeks — with Irish Water billing €271m over the next year.

The quarterly charges will be a maximum of €40 for a single adult household and €65 for a two-adult household.

However, it has emerged that around 11,000 customers who submitted payment details in writing or over the phone have been asked to re-submit the information.

Under legislation due to be signed off on by Government after the Easter break, more than 400,000 people who are still refusing to pay will see their water charges removed directly from their pay slips or social welfare.

The rules will allow for court cases from next year as a “last resort” for people who continue to refuse to pay after 15 months of bills.

The legislation — which will go before the Dáil in early summer to convince EU officials of the financial viability of Irish Water — will also outline a “payment plan” for people who genuinely cannot afford the fees.

However, despite the hardline stance, opposition to Irish Water shows no sign of abating, with Sinn Féin due to publish a water services repeal bill this morning, calling for the company and its charges to be scrapped.

Elizabeth Arnett, head of communications at Irish Water, said that forthcoming legislation to address those who refuse to pay water charges is a matter for the Government, but that the utility has its own measures including additional charges for people who will not pay.

Related: Irish Water: Colour of hall door needed to get right water bill

“As it stands, four bills will be issued before any additional charges will go onto the bill,” she said.

“If a customer hasn’t engaged with us at all and they are on the €260 rate, the additional charge will be €60; if they are on the €160 rate, which would be a single adult household, the additional charge is €30.

“The Government has signalled that their intention is to look at additional measures in this area, so when they have made a policy decision in relation to this, then we will wait and see what will happen.

“We already have measures in place with regard to customers who won’t pay, there will be the commercial courts as you would normally have for any type of debt and there are the additional charges that will go onto the bill after a year.

“There were previously measures in place where we could reduce water to a trickle, that’s absolutely not on the cards here and that separates us and makes us different from other utilities. We don’t have the means, nor should we I think, to cut off water services to people,” she said.

Here's what your Irish Water bill will look like. pic.twitter.com/tIDtY16QAH — Joe Leogue (@JoeLeogue) March 25, 2015

Irish Water will make a distinction between those who can’t pay and those who won’t pay, she said, and those in difficulty who engage with the utility can avail of extended credit terms and payment arrangements.

She also revealed that Irish Water expects that most of the boil water notices affecting Roscommon will be lifted in the coming weeks, something she described as a significant achievement for a “flagship issue”.

Ms Arnett was speaking yesterday in Irish Water’s Abtran Call Centre in Cork, where the number of customer service agents employed to handle calls and queries has risen to 750 to handle the influx of questions about the first bills.

Abtran management revealed that since last October it has reported three letters it has received to gardaí, including a high-profile incident last November when an Irish Water registration pack smeared in human excrement was received at the Cork call centre.

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