Road Flooding Education & Signage

The number one cause of death during flooding is by driving through flood water and in recent years there have been several high-profile deaths in Derbyshire (2021) and Liverpool (2023) involving investigations into actions of the local councils.

Author: Dr Matthew Watkins, Senior Lecturer in Sustainable Product Design Engineering

Publication date: July 2026

Climate change is leading to greater incidents of extreme and prolonged high rainfall leading to flooding particularly in the northern hemisphere, therefore this is expected to become a growing issue.

Against this backdrop my research has found:

There is a lack of information on how to safely drive through and when to avoid flooded roads when in a car.

  • There is an absence of instructions or acknowledgement in the UK highway code, concerning flooding and driving through floods, standing water or how to ford water safely.
  • There are no public awareness or advertising campaigns like there are in Australia, New Zealand and USA.
  • UK motorists underestimate the risk of driving through flood water and don’t recognise the risk flowing flood water

Existing road flood signage is ineffective and inadequate to warn drivers of road flooding.

  • Static flooding signage being mistrusted by motorists due to its prevalence and lack of removal after flooding has subsided.
  • Dynamic road flooding signage is more effective, as evidenced by higher recall and by nature can respond to the specific environment parameters immediately engendering greater trust amongst motorists.

The recommendations from my research highlight the need for a greater understanding and indication of the dangers of road flooding.

  • To include detail in the highway code on flood water and the use of fords to encourage drivers to determine safe depths less than 300mm and recognise water flow.
  • To rollout dynamic flood signage in key flood prone areas with sensors to permit autonomous activity and real time monitoring.
  • To highlight the risks of road flooding through a targeted autumn driver awareness campaign.

I would be very happy to discuss or present my findings on this topic further.

The full research paper titled ‘An investigation into driver's perceptions of road flooding and adherence to signage’ can be found in the Journal of Transportation Research Part F: Psychology and Behaviour: https://www.sciencedirect.com/science/article/pii/S1369847826001348