Long term investment scenarios and an opportunity to collaborate

¹ Environment Agency, Kingfisher House, Goldhay Way, Orton Goldhay, Peterborough, UK
² Environment Agency, Ergon House, Horseferry Road, London, UK

^a Corresponding author: mike.steel@environment-agency.gov.uk

Abstract

In December 2014 the Environment Agency published Long Term Investment Scenarios (LTIS) for flood and coastal erosion risk management in England. It sets out the future costs and benefits of managing flood and coastal erosion risk in England in a range of different scenarios. Its major achievement in long-term risk-based resource allocation is to incorporate a rigorous national economic optimisation based on an aggregation of 3,000 flood defence systems covering the entirety of England’s floodplain. The analysis is based on the Environment Agency’s national assessment of flood risk from rivers and the sea, along with the risk of properties flooding from surface water. The risk information informs an innovative economic model to assess optimal levels of investment both in maintaining and improving the defence infrastructure, and is combined with a high level appraisal of investment in broader risk management activities (such as flood incident management). The headline results describe optimal investment profiles in the short and long term, and compare these with planned investment levels by government and external contributors. The potential to reduce flood risk in the long term is described in the context of the efficiencies required to reduce and hold down costs, the benefits of maintaining control over development in the floodplain, and the effects of climate change. There are constraints in the economic optimisation approach, as well as in the broader, inclusive overview of risk management activities, and the Environment Agency is now seeking a more open, collaborative approach – working with industry and academic partners – to develop LTIS and strengthen it further as robust, independent, world-leading evidence.