Combining probabilities from different factors to improve the design of flood defences

This project mapped the dependencies between environmental events to find ways of using joint probabilities of them happening when designing flood defences.

Documents

Dependence between extreme sea surge, river flow and precipitation - a study in South and West Britain (3.4 MB) PDF

Dependence between extreme sea surge, river flow and precipitation - a study in South and West Britain - technical report (5.79 MB) PDF

Joint probabililty dependence mapping and best practice - final report (32 KB) PDF

Joint probability dependence mapping and best practice - technical report on dependence mapping (3.8 MB) PDF

Joint probability dependence mapping and best practice - summary (85 KB) PDF

Joint probability dependence mapping and best practice - technical report interim product (4.5 MB) PDF

Use of joint probability methods in flood management - a guide to best practice - technical report (2.5 MB) PDF

Joint probability - dependence mapping and best practice - software (245 KB) EXCEL

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Details

The combined effect of two or more extreme environmental factors (waves, tide, surge, river flow, rainfall, swell and wind) usually make it more likely that floods will happen. This project used dependence mapping and developed test practice guidelines to encourage using probability methods that combine factors to improve how flood defences are designed.

The results of this project are relevant to most flood risk and defence design calculations. The results would be used mainly by practitioners, such as flood defence designers, but would also be of interest to policy makers, regulators and researchers.

The technical reports are aimed at various audiences from non-specialist users of joint probability methods (encouraging them to adopt the methods without the need for specialist advice) to more experienced users. They also present detailed results from the river flow, surge and daily precipitation analysis, including some time-lagged and spatially separated dependence analyses. These will be useful for hydrologists.

This project ran from 2001 to 2005 at a cost of £225,191.

Updates to this page

Published 16 February 2021