Reliability and resilience of flood detention (storage) reservoirs

There are now around 200 large flood detention reservoirs (FDRs) in England, typically designed to attenuate floods and thus prevent flooding downstream for events with an annual exceedance probability up to 1 in 100, sometimes but not always with provision for climate change. There is some evidence that these structures do not always provide the intended standard of protection and this paper explores the available data and possible reasons for this. The paper concludes with some suggested simple sensitivity tests to examine the reliability and resilience of a FDR in attenuating floods, including the impact of climate change.