A 365 year flood frequency curve for the Avon at Salisbury, UK
Flood flow data for permeable catchments are scarce and these often lack extreme values. Recent advances in flood frequency analysis have not succeeded in estimating rare floods on permeable catchments with much certainty. Measured flow data can be augmented by historic flood data. The Avon at Salisbury UK drains an area of 399 square kilometres. Using newspaper records, an archive flood report, and a historic chronology, a flood history for the past 365 years has been established. Flood levels were converted into discharges using hydraulic equations. The 1915 flood event served as a benchmark event from which the peak flow of other rare events could be estimated. The results showed that the 1635 flood had a peak discharge in the range 66-74 cumecs, about twice the largest measured flood of December 2000. All the historic floods had runoff rates of less than 0.2 cumecs per square kilometre, illustrating the low runoff rates on a largely permeable catchments.
Bibliographic Reference: An oral report given at: The International Workshop - River Runoff: Minima & Maxima. Held in: Saint Petesburg (RU), 6-8 June 2001
Record Number: 200114160 / Last updated on: 2001-12-21
Original language: en
Available languages: en