Flood Plain

The River Thames has flooded several times in living memory, although in the Maidenhead area the risk has been reduced in recent years by the cutting of the Jubilee River – a flood relief scheme.

With the effects and extent of global warming as yet unknown, this may only bring a temporary reprieve.

The following is a direct link to the relevant Environment Agency we page, which needs to considered alongside information from the planning office as to the treatment of this information for planning purposes, and the views of your insurers.



1. Floodplain
A floodplain is the area that would naturally be affected by flooding if a river rises above its banks, or high tides and stormy seas cause flooding in coastal areas. 

There are two different kinds of area shown on the Flood Map. They can be described as follows:- 

  • Dark blue http://www.environment-agency.gov.uk/commondata/figureimages/floodmap_dkblu.gif shows the area that could be affected by flooding, either from rivers or the sea, if there were no flood defences. This area could be flooded:
  • from the sea by a flood that has a 0.5% (1 in 200) or greater chance of happening each year
  • or from a river by a flood that has a 1% (1 in 100) or greater chance of happening each year.
  • Light blue http://www.environment-agency.gov.uk/commondata/figureimages/floodmap_ltblue.gif shows the additional extent of an extreme flood from rivers or the sea. These outlying areas are likely to be affected by a major flood, with up to a 0.1% (1 in 1000) chance of occurring each year.

Clearly this information is not conclusive as to the possibility of future flooding, but it does condition what and where planning approvals may be given.