By Joe Boyle
BBC News website
More than 30,000 people have asked about meters ahead of the introduction of water charges, the government says.
The water charges have proved to be controversial
They have called the Department for Regional Development's water charge helpline since 3 February wanting to know about the devices.
But only new buildings and pensioners' homes will be eligible initially. Consumer groups believe meters should be more widely available.
The new charging system, linked to the value of homes, starts in April.
Meters would allow people to pay for the amount of water they actually use, rather than being charged according to house prices.
The department said it had taken 42,249 calls this month - 84% of which were "meter queries".
CALLS TO WATER HELPLINE
Meter queries - 84%
General inquiries - 7%
Payment options - 3%
Data changes - 2%
Other - 3%
A spokeswoman said the government wanted to introduce the devices "across Northern Ireland".
But she added: "To manage the installation of meters, we are offering certain consumer groups the opportunity to apply first."
These "consumer groups" include pensioners aged above 60, and any householder being connected for the first time.
The department is sending out "meter packs" containing an application form. They aim to install a meter within six months of the request being received, she said.
Official estimates suggest the devices could be fitted at a rate of 2,000 to 3,000 a month.
The new charging system - to be phased in over three years - is being introduced because the government wants water and sewerage services in Northern Ireland to become self-financing.
But the decision has proved highly controversial - with critics arguing that the government has not justified the soaring bills.
Northern Ireland's consumer council took the government to court over the issue.
The council's chief executive, Eleanor Gill, told the BBC the situation was "crazy" and said linking bills to house prices was "a nonsense".
"It isn't fair, it's not affordable and it doesn't seem to do what it was set up to do - protect the precious natural resource of water."
She called for more widespread metering, saying it would allow people to manage the amount of water they were using - just as they do with gas and electricity.
'No blanket advice'
Meanwhile, Age Concern said many older people were angry and confused over the charges.
"This is another demand on their income that they are worried about how they'll meet," said Elaine Campbell, the charity's head of policy.
But she urged older people to make sure they apply for the "affordability tariff" - a reduction on bills given to low-earners and those on benefits.
"We are not putting out blanket advice to everyone - you need to look at your own circumstances," she said.
"For example, if you are entitled to benefits or have an income near benefit level, you may be eligible for a reduced bill."
The government's water charges helpline is 0800 0515446.