Homes that miss register deadline can still avail of €100 water grant

And some of the 600,000 homes which had not signed up with the utility by yesterday afternoon may also not be disadvantaged in any way if they miss the deadline.

Irish Water sources admitted a failure to do so will only mean there is no guarantee of "correct billing" of water usage.

Homes have until midnight tonight to register with Irish Water - but a spokesperson said just over one million people had returned forms.

However, that figure includes 150,000 households which are not on the public mains system but have still registered their details, as well as households that returned their form but did not provide any billing details.

This means only 850,000 of the company's 1.5 million customers had submitted details by yesterday evening.

The company said it would continue to accept the return of forms after the deadline - but that homes run the risk of not being charged accurately when the first bills arrive in April.

However they may still be able to get the €100 grant.

In a statement, the company said: "As of midnight tomorrow, the default charge of €260 applies to household who have yet to confirm their details.

"Irish Water is today urging households who have not yet confirmed their details to do so now to ensure that they get the correct bill and also to make sure that they can avail of the Government's €100 Water Conservation Grant."

The Department of Environment confirmed yesterday another deadline will be put in place by which point households must register to avail of the €100 water conservation grant - which was a late addition to the Water Services Bill and introduced as a sweetener following mass protests.

A department spokesperson said: "The grant is being paid on a universal basis to all householders in respect of their principal private dwellings.

"It is important that all households have an equal chance to reduce their water consumption in their primary dwellings, whether they have already been paying for water privately or are about to pay for public water services."

The grant is due to be issued in September with the deadline to apply likely to be some time in the summer.

Fianna Fáil environment spokesman Barry Cowen said there had been a "poor return by the deadline set" and called on the Government to reveal how they plan to deal with non-compliance.

"The expected legislation will deal with those who are non-compliant and we await the detail to see how the Government believe they can further force people to be compliant."

Speaking in relation to ensuring more people register with Irish Water, Taoiseach Enda Kenny said the legislation dealing with compliance would be drafted shortly.

"The minister has already made it clear on a number of issues that nobody will be cut off in terms of their water supply.

"But I would hope that everybody is of the understanding that this is a very small contribution for a very valuable resource," he said.