Developing surface water flood forecasting capabilities in Scotland: an operational pilot for the 2014 Commonwealth Games in Glasgow

Existing surface water flood forecasting methods in Scotland are based on indicative depth-duration rainfall thresholds with limited understanding of the likelihood of inundation or associated impacts. There is a requirement to develop innovative risk-based solutions to improve surface water forecasting capabilities in support of improved flood resilience in urban centres. A new model was developed for Glasgow linking 24 hour ensemble rainfall predictions from MOGREPS-UK with static flood risk maps through the Grid-to-Grid hydrological model. The model was used operationally by the Scottish Flood Forecasting Service during the 2014 Commonwealth Games to provide bespoke surface water flooding guidance to responders. The operational trial demonstrated the benefits of being able to provide targeted information on real-time surface water flood risk. It also identified the high staff resource requirement to support the service due to the greater uncertainty in surface water flood forecasting compared to established fluvial and coastal methods.