Quantifying the hydrology of the East Devon floods of October 2008

Dr Paul Webster

Director: Hydrology & Water Resources, Hydro-Logic Limited, Old Grammar School, Church Street, Bromyard, Herefordshire, HR7 4DP

pwebster@hydro-logic.co.uk www.hydro-logic.co.uk www.timeview.net.

Following the East Devon (Ottery) floods of October 2008, Hydro-Logic was commissioned by the Environment Agency to undertake hydrometric analysis of the event. The principal issues to be addressed were the definition of the rainfall field and a review of rating relationships for key gauges. Following a description of the event, the presentation summarises the main findings. These include the methodology for defining the rainfall field, the derivation of rating relationships and the hydrological context for the event. The presentation highlights some of the key difficulties that are associated with quantifying extreme events.