Coastal flood boundary conditions for the mainland UK coasts and islands

Best practice guidance and data on boundary conditions on coasts, such as storm tides and extreme sea levels.

Documents

Published in 2019

Coastal flood boundary conditions for the UK 2018 update - technical report (10.4MB) PDF

Coastal flood boundary conditions for the UK 2018 update - user guide (1.6MB) PDF

Coastal flood boundary conditions for the mainland UK coasts and islands - summary (88KB) PDF

Published in 2011 (for reference only)

Design sea levels - technical report (3.9MB) PDF

Design swell waves - technical report (4.6MB) PDF

Practical guidance design sea levels - technical report (1.7MB) PDF

Practical guidance swell waves - technical report (1.3MB) PDF

National design sea levels - levels and spatial data (744KB) ZIP

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Details

Project update (2019)

Successful risk-based flood and coastal erosion risk management requires the best available information on coastal extremes. This best practice guidance updates and replaces advice given in ‘Coastal Flood Boundary Conditions for UK Mainland and Islands. Design Sea Levels’ published in 2011. Work was carried out in 2017 to 2018 to develop and apply improved methods to update coastal extreme sea levels using a longer data record. The locations for which extreme sea levels are provided were also extended to include Northern Ireland and some estuary locations.

The aims of the update were to provide: * a consistent set of extreme sea levels around the coasts of England, Wales, Scotland and Northern Ireland * a means of generating appropriate total storm tide curves for use with the extreme sea levels * best practice guidance on how to use these new datasets

Original research 2011 (for reference only)

The project produced a number of very useful outputs which fed into:

  • coastal flood modelling and mapping
  • scheme design
  • strategic planning purposes (Shoreline Management Plans) and Flood Risk

Assessments (at all levels) included:

  • a consistent set of design sea levels around Great Britain
  • a consistent set of design swell waves around Great Britain
  • best practice guidance on applying these datasets
  • levels and spatial data - most free and commercial GIS will be able to open, manipulate and view the files
Published 24 February 2021