Flooding can be caused by the sheer volume of water or indicate a blockage or maintenance problem with the system. Any flooding or drainage issue should be reported so that it can be dealt with and the system checked for adequacy.
If you believe the flooding is from a main river contact the Environment Agency.
Burst or leaking water main or foul water sewer
If the issue you are reporting has or could cause injury or danger to life, then please call 0300 555 1388 so we can process it as an emergency.