Emergency crews are braced for floods in Cambridgeshire after a warning the Great Ouse may burst its banks.
A police spokesman said they were "preparing for potential problems" in the areas surrounding St Neots and in low-lying areas of the Fens.
Floods were possible over the next 24 hours and they wanted local people to be prepared, a police spokesman said.
Drivers were advised to avoid places where flood warning signs are and homeowners urged to move possessions.
Planning teams involving the emergency services, councils and the Environment Agency have met to discuss the possible problems.
The police spokesman could not give any information on when floods might occur and what volume of water might be involved.
But he added the Great Ouse was expected to break its banks in north Bedfordshire at sometime on Tuesday.