Flood map shows risk across city

The Rivers Agency’s Strategic Flood Map shows how flood defences are in place in certain areas including Drumahoe and along the Westbank of River Foyle upstream of the Craigavon Bridge.

The map also shows a mottled patchwork across hilly Londonderry illustrating areas where heavy rainfall can submerge streets and roads in surface water deeper than 100mm.

The flood plains of the Foyle and Faughan (pictured) are the relatively flat areas of land adjacent to rivers that are subject to periodic coverage by floodwater.

The outlines of the floodplains highlighted in the map identify the areas that in any year have a 1 in 100 or greater chance (1 per cent Annual Exceedance Probability (AEP)) of flooding from a river.

The extents of the floodplains have been estimated using predictive computer modelling techniques that are commonly used as a decision support tool by flood defence authorities throughout the UK, Ireland and beyond.

They should be regarded as ‘indicative’ of the general areas that are estimated to be prone to flooding and are not suitable for determining the flood risk to a particular property or specific point location.

Agriculture and Rural Development Minister Michelle O’Neill said: “Flooding can cause major damage and disruption and by providing information we can all better manage flood risk. I see the Strategic Flood Map as an essential tool as it enables everyone to understand the risk they face.

“Using the information available and by working together, the public and other responsible bodies, such as my Rivers Agency, can help reduce the impact of flooding on people, property and the natural environment.

“The updated on-line information will also allow people living or working in areas at flood risk from rivers, sea and heavy rainfall to take necessary precautions now and in the future.”

Environment Minister Alex Attwood said: “I welcome the continuous improvements in the information relating to flood risk and also the joint guidance on the application of the Surface Water Flood Map. This will enhance the planning system and is a good example of joined-up government.”