Water companies in England and Wales are set to reveal proposed increases to water bills for a five-year period.
Welsh Water says its average household bills will only rise at the rate of inflation after 2010.
The firms must submit their spending and pricing plans from 2010 to the industry regulator Ofwat on Monday.
The watchdog will decide whether to allow above-inflation price rises at a time when other bills have gone up.
Thames Water has already announced it expects bills to rise by about 3% above inflation a year, and Northumbrian Water said its would be 1.3% above.
Thames Water has already announced it expects bills to rise by about 3% above inflation a year, and Northumbrian Water said its would be 1.3% above.
The news comes as water firms in England and Wales set out planned rises to water bills for a five-year period.
All firms must submit their spending and pricing plans from 2010 to the industry regulator Ofwat on Monday.
The watchdog will decide whether to allow above-inflation price rises at a time when customers are being hit by other rising bills.
Customer concerns
Customer concerns
Ofwat chief executive Regina Finn said: "This is the start of the process of making decisions on how each company proposes to provide value-for-money, long-term, high-quality water services to its customers.
"This is the start of the process of making decisions on how each company proposes to provide value-for-money, long-term, high-quality water services to its customers," said Ofwat chief executive Regina Finn.
"We will now examine draft business plans in detail, checking the proposed level of service and investment.
"We will now examine draft business plans in detail, checking the proposed level of service and investment.
There will be an inevitable impact on bills, but even so, we will be able to keep them below the industry average David OwensThames Water chief executive
We have to make sure that our infrastructure, our networks, our treatment works are all ready to cope with [an] influx of people Peter AntolikThames Water director of regulation
"We will make sure each plan includes everything we expect, takes account of concerns expressed by customers, and does so as efficiently as possible."
"We will make sure each plan includes everything we expect, takes account of concerns expressed by customers, and does so as efficiently as possible."
Each water company is expected to put a summary of its draft business plan on its website.
Ofwat is due to make its final decision by November 2009.
Ofwat is due to make its final decision by November 2009.
Thames Water, the UK's biggest water company, said its £6.5bn investment plan would be the largest spending programme carried out by a UK water company.
Thames Water, the UK's biggest water company, said its £6.5bn investment plan would be the largest spending programme carried out by a UK water company.
The company's chief executive David Owens said: "Thames' customers have enjoyed the lowest bills in the industry for many years, but we now need to make essential investment to secure their services for the future.
The firm said its customers had "enjoyed the lowest bills in the industry for many years", and while there would be "an inevitable impact on bills", it would try to keep charges below the industry average.
"This is particularly true for London, where the water and sewerage infrastructure is ageing.
Peter Antolik, Thames Water's director of regulation, told BBC Radio 4's Today programme that the money was vital to improve London's ageing water system.
"There will be an inevitable impact on bills, but even so, we will be able to keep them below the industry average."
"We also have, it should be remembered, a growing population in London and the south east," he said.
"We have, we estimate, about 380,000 more people coming in to the region and we have to make sure that our infrastructure, our networks, our treatment works are all ready to cope with that influx of people."
Household bills
Household bills
While most companies are likely to ask for above-inflation increases, they are unlikely to be anything like as high as recent gas and electricity price rises.
While most companies are likely to ask for above-inflation increases, they are unlikely to be anything like as high as recent gas and electricity price rises.
However, consumers do not have a choice who they get their water from.
However, consumers do not have a choice who they get their water from.
Ofwat said in February that average bills across England and Wales would rise by 5.8% this year, with increases of 8% in some areas.
Ofwat said in February that average bills across England and Wales would rise by 5.8% this year, with increases of 8% in some areas.
The regulator has said increases in bills are projected to be 42% in real terms by 2010 since the privatisation of the water industry in England and Wales in 1989.
The regulator has said increases in bills are projected to be 42% in real terms by 2010 since the privatisation of the water industry in England and Wales in 1989.
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