Flood risk changes! New Guidance recognises that flood risk is changing
Environment Agency: Development of interim national guidance on nonstationary fluvial flood frequency estimation Project summary FRS18087/IG/S We have developed new tools and techniques to help us detect and take account of non-stationarity in flood frequency estimation for flood scheme appraisal. Background Traditional methods used to estimate the probability and magnitude (size) of floods (flood frequency analysis) assume that extreme events are ‘stationary’. This is where observations of past flood events are assumed to represent the behaviour of future events. Recent high magnitude flood events on our rivers have prompted many hydrologists to question the concept of stationarity and instead consider ‘nonstationarity’ which recognises statistically significant changes over time. Clear to access the reports
Updated wave overtopping and assessment manual (EurOtop) and calculation tool (Bayonet GPE)
This new manual offers up-to-date guidance to help users more accurately predict the rate of waves overtopping sea defences. It is an update to the 2008 Wave Overtopping and Assessment (EurOtop) manual, a widely accepted, international best practice tool. It shares the best approaches for assessing overtopping in different scenarios, improving coastal flood forecasting and delivering more cost effective design of coastal flood defence schemes. It is accompanied by an online calculation tool (Bayonet GPE) which helps users produce overtopping predictions for different types of sea defences, including embankments and dikes, rubble mound structures and vertical structures.