Guidance

Flood estimation guidelines

Find out about flood estimation methods, the data you need to estimate flood flows, and levels of uncertainty.

Applies to England

Documents

Flood estimation guidelines

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Details

You should use these flood estimation guidelines for river flood management and reservoir safety applications.

The guidelines:

  • provide a framework for selecting flood estimation methods
  • acknowledge that flood estimates are uncertain and outline how to calculate confidence limits
  • address common shortcomings in hydrology reports

The guidelines also emphasise the need for a risk-based approach to flood estimation and a thorough evaluation of flood studies.

Updates to this page

Published 8 November 2023

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