Developing our flooding knowledge
As the strategic flood risk management authority in Scotland we are continually working to develop and improve our knowledge of the sources and impacts of flooding. We have developed a knowledge base of methods, guidance and summaries that may be useful to responsible authorities, academic projects and consultants delivering flood risk management projects, which can be accessed below.
- National Flood Risk Assessment
- Flood maps
- Surface water flood forecasting
- Flood Reports
- Flood risk management and climate change
- Gravel deposits and flood risk to agricultural land
- Light detection and ranging survey (LiDAR)
- Natural Flood Management
National Flood Risk Assessment
First published in December 2011, the NFRA has provided Scotland with the knowledge and tools to assess the causes and consequences of flooding. We work with key stakeholders to periodically review and update the NFRA every six years, ensuring that we can effectively support sustainable flood risk management in Scotland.
The National Flood Risk Assessment 2018 and data explorer tool is now available. There have been a number of changes since the 2011 NFRA including advances in how properties at risk have been identified.
For more information, you can view our NFRA animation or our Frequently Asked Questions.
For information on Flood Risk Management in England, you can visit the Environment Agency website
Flood maps
A key milestone of the Flood Risk Management (Scotland) Act 2009 was the production of flood hazard and flood risk maps. A summary of the methods used to produce the maps, including assumptions and interpretation guidance, are available below.
- River flooding summary
- Coastal flooding summary
- Surface water flooding summary
- Groundwater summary
- Natural flood management summary
- Natural susceptibility to coastal erosion summary
- Impacts of flooding summary
- Future flood maps summary
Flood modelling guidance has also been developed, which provides a common technical basis to support responsible authorities in the planning, development and use of flood models to inform flood risk management decisions.
In addition, a Local Authority Flood Study Checklist has been developed to provide support to local authorities and other commissioning authorities when undertaking scoping studies to inform sustainable flood risk management.
Additional information on surface water flooding may be available from local authorities that have undertaken an integrated catchment study in partnership with Scottish Water. Studies were undertaken for Aberdeen, Falkirk, Dundee Tayside (focussing on Dundee to Arbroath), Edinburgh and across the Ayrshire Local Plan District (focussing on Ayr, Irvine and Kilmarnock).
Surface water flood forecasting
SEPA’s Flood Warning Development Framework for 2017-2021 includes a commitment to explore and trial innovative approaches to pluvial (or surface water) flood forecasting.
As a preliminary step towards this, we commissioned in 2019 an assessment, carried out by RAB Consultants and the University of Strathclyde, of the current state of the relevant science, including precipitation observations and forecasting, as well as available tools for flood modelling. The remit of this study was to review available options, considering the advantages and disadvantages of each, and how they may be applied to surface water flood forecasting in Scotland.
The study, towards improved surface water flood forecasts for Scotland, concluded that the approach currently used by SEPA, including indicative depth-duration thresholds and the Scottish Flood Forecasting Service (SFFS) Heavy Rainfall Alert (HRA) tool, is consistent with international best practice, but that there are tools available that could be used to deliver an improved product at either national or city scale.
Following delivery of this report, we intend to further develop our capabilities in forecasting surface water flooding over the coming years, building on our experience of delivering the first operational surface water forecasting tool during the Glasgow 2014 Commonwealth Games and working in partnership with the Met Office through the Scottish Flood Forecasting Service and with responders in Scotland.
Flood Reports
We have created a report to present information on the thunderstorms of the 11 and 12 August 2020 and the resulting flash floods. This largely factual report is to help communicate important hydrological data from the event and to help those interested in the scale of this extreme and notable rainfall. The report is intended to inform future knowledge and understanding of extreme short duration flood events in Scotland.
The Flash Floods of 11 and 12 August 2020 Report
Flood risk management and climate change studies
We are working to improve our knowledge of climate change in Scotland and its impact on river flows, weather patterns and sea level rise.
In 2011, we commissioned the Centre for Ecology & Hydrology (CEH) to undertake an evaluation of the risk of fluvial flood flow changes across Scotland. A report and summary report of the project have both been produced.
The UK Climate Projections 2018 (UKCP18) were launched on 26 November 2018 and offer state-of-the-art information on the future climate of the UK to 2100. SEPA will use UKCP18 data in:
- Updated guidance for land use planning;
- Providing robust advice to ensure planning decisions are well informed and new developments are not located in high risk flood areas;
- Coastal, River and Surface Water flood hazard maps;
- Future National Flood Risk Assessments (NFRAs) and Flood Risk Management (FRM) strategies.
- Supporting Scotland to adapt to climate change and be resilient to future flood risk.
Gravel deposits and flood risk to agricultural land
Following the extraordinary flooding of winter 2015/16, SEPA agreed to NFU Scotland’s request to examine the role played by sediment deposits in flooding at three different sites across Scotland – the River Feshie where it meets the River Spey, the River Tay near Ballinluig, and the River Dee at Ballater. That work is now complete and full details can be found in the final report - Gravel Deposits and Flood Risk to Agricultural Land.
Light Detection and Ranging (LiDAR)
SEPA, in partnership with Scottish Water, local authorities and Scottish Government has collected LiDAR data to support the delivery of flood risk management in Scotland. This data is available under Open Government Licence from the Scottish Remote Sensing Portal.
Natural flood management
Natural flood management (NFM) is part of the catchment led and sustainable approach to flood risk management implemented by the Flood Risk Management (Scotland) Act 2009. A map showing areas where further detailed assessment should take place are featured on our flood maps. The map should be considered alongside guidance on how areas where identified and how to interpret the information.
We have published the Natural Flood Management Handbook to provide a practical guide to the successful implementation of natural flood management. We also help oversee the NFM Network Scotland, a new platform for those working in natural flood management to share news, information and case studies.
To help us learn more about natural flood management we are working with organisations, researchers and charities to run demonstration and research projects like those on the Allan Water, the Eddleston Water and Firth of Forth Futurescapes. We are also looking at how we can integrate flood risk management and river basin management objectives through the pilot catchment project.