Hikes of up to 3.4 percent a year for customers have been requested under the providers' 2010-15 plans.
Water firms from England and Wales handed in their final business plans for the 2010-15 period to the regulator yesterday.
Ofwat will now analyse the documents, before agreeing on final versions of the business strategies. Included in the plans are customer prices and proposed infrastructure investments from each water provider.
The economic downturn has led to the firms requesting sharp price hikes for the five-year period. Northumbrian Water said that it wanted increases to customer costs of 3.4 percent a year. United Utilities requested a 1.8 percent rise, while Severn Trent wants 0.8 percent a year increase.
Ofwat had asked the firms to provide more general long-term strategies for the next 25 years in the documents. Issues including how the providers would deal with climate change and how they would meet consumer expectations were also to be incorporated, the watchdog said.
Regina Finn, the watchdog's chief executive, added: "Consumers are at the heart of our decision making. We will now scrutinise final plans and challenge them as necessary. We will do everything possible to secure sustainable, value-for-money services for consumers."
Five-year plans begin being enforced from April 2010, with Ofwat scheduled to set draft price limits in July.
