Research and analysis

Flood and coastal risk management: long-term investment scenarios

How different scenarios affect investment in flood and coastal erosion risk management.

Applies to England


Long-term investment scenarios (LTIS) 2014

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The long-term investment scenarios (LTIS) are an economic assessment showing what future flood and coastal erosion risk management (FCERM) could look like over the next 50 years in England. LTIS sets out the total national level of investment if we invest in all the places where the benefits are greater than the costs. This is called the optimum level of investment for FCERM.

This study takes into account:

  • climate change
  • how development on flood plains is managed
  • future costs and benefits of managing flooding and coastal erosion

LTIS is evidence which government and others will use to consider future policy and investment choices. It is a set of national scenarios which describe possible ‘What if …?’ futures, but does not predict which of these futures will happen.

The Environment Agency produced LTIS 2014 and LTIS 2019.

In addition to LTIS 2019 there is a LTIS 2019 Technical Summary which contains the technical detail of the new analysis. Contact the Environment Agency for a copy of the LTIS 2019 Technical Summary.

Published 1 June 2009
Last updated 1 July 2021 + show all updates
  1. Section 9.4 updated to remove the beta (prototype) visualizer tool link, as this is no longer supported by the Environment Agency.

  2. Minor edits made in response to comments from peer reviewers, to improve clarity, language and add some context around uncertainties. In particular, the changes in Section 11 improve the description of how the new best estimate of the optimum level of investment was derived.

  3. The long-tern investment scenarios 2019 had an incorrect year in the URL. New addition published with correct URL.

  4. The long-term investment scenarios published in 2014 has been updated with the long-tern investment scenarios 2019.

  5. Long-term investment strategy published in 2009 has been updated with the Long-term investment scenarios 2014.

  6. First published.