UK Flood Map

Fathom-UK offers comprehensive flood hazard modelling for
the whole of the United Kingdom

Fathom's UK Flood Map
Fathom's UK Flood Map - Carlisle fluvial defended flood simulation

Fathom’s UK Flood Map, Fathom-UK, offers an alternative view of flood risk against existing government data, projecting changes in hazard across multiple different climate scenarios. Achieved through combining world-leading research and cutting edge modeling techniques with data like UKCP18, UK Flood Map offers users to critically assess the impact of flood risk against any portfolio, book of business or asset.

Product key features


Climate Dynamics

5 climate scenarios across 3 time horizons – Utilizing UKCP18 climate data to produce scenarios for present day, 2030, 2050 and 2070.


10 return periods

Ranging from 1:5 year to 1:1000 year. Return periods can be categorised to suit your risk appetite.



Unique detection algorithm that identifies flood defenses where data are not available.


Inland and coastal flooding

Fluvial, pluvial and coastal flooding – Assess the risk from different types of flood including defended and undefended views



Gain instant on-demand access via the Fathom API and Fathom Portal, host the data on-premise

Learn how to access Fathom’s data


~10 meter resolution

About the map Created by some of the world’s leading academics and scientists in climate risk and hydrology, Fathom’s UK Flood Map is based on pioneering methods developed in-house

Underpinned by decades of peer-reviewed research, our model couples decades of scientific research with the latest hydraulic modeling techniques.

The result is flood hazard data that can provide high-resolution predictions for current and future climate scenarios – a first for flood modeling in the UK.

By integrating these datasets into Fathom’s hydraulic modeling framework, UK Flood Map yields multiple return periods for every river channel in the country.

We have achieved this through Fathom’s unique channel solver methodology, which explicitly represent river channels in the absence of accurate hydrographic information.

When incorporated alongside precise terrain data, multiple perils and defense algorithms, users are presented with a dataset that effectively represents the impact of climate on flood risk, rather than relying solely on historical records.

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Quote We would like to express our gratitude to both the physical risk open data providers as well as to the plethora of technical experts for all of their contributions to this exercise over the past two years.

Quote Fathom is an innovative and dynamic organisation at the forefront of flood risk research. They offer a range of specialist modelling tools and use a clear and impressive methodology.

Quote Fathom’s most recent release – Fathom-Global 3.0 – provides flood maps for anywhere in the world, and at improved levels of detail, providing information to help decision makers better manage their future flood risk by considering climate change and the associated uncertainty.

Quote Aon and Impact Forecasting can now more holistically approach clients’ flood risk management and quantification needs thanks to our collaboration with Fathom.

Model features Model features

    Pluvial flood For pluvial perils, Fathom’s UK Flood Map accounts for drainage systems, flash flooding and infiltration across a variety of terrain


    Flooding simulated for even the smallest flow pathways.


    Extreme precipitation magnitudes using data from UK Centre for Ecology and Hydrology (CEH).


    Channel drainage is explicitly represented.

    1 in 100 year pluvial flood simulation of Reading, UK.

    Fluvial flood When modelling fluvial, Fathom-UK accurately represents extreme river flows at any point for every UK river.


    Flows based on the entire NRFA gauge record.


    Multiple return periods.


    Comprehensive defence representation.

    1 in 1000 year fluvial flood simulation of Nottingham, UK.

    Coastal flood We account for multiple coastal scenarios including sea level rise, high tides and storm surge.


    100% coverage of the United Kingdom’s coast.


    Extreme water level scenarios taken from the Environment Agency


    Tide gauge data and wave setup estimates based on ECMWF.

    1 in 100 year undefended coastal flood simulation in Avonmouth, under a 2070 climate scenario.

    How to access Fathom’s UK Flood Map

    Fathom API

    Fathom API - Brain icon

    Self serving, seamless data provision using Fathom’s cloud-based API. By using the API, Fathom’s users get on-demand access to the entire UK Flood Map.

    Fathom Portal

    Fathom Portal - Desktop icon

    If you do not have an in-house platform solution, Fathom’s portal offers an interactive platform by which users can host, view and analyse data. If you are interested in this solution, you can trial the platform using Fathom sample data for free. Request a trial here.

    Direct Provision

    On premise - Pin

    If you would prefer to host the data on-site, Fathom can provide you with GeoTIFF files that can be integrated within your internal systems and data viewers.


    Fathom partners

    Whether you are in need of advanced consulting, geocoding or already have an existing platform that you are working with, Fathom’s data can seamlessly integrate with a wide range of platforms for your analysis. Get in touch to enquire about a platform or learn more about our existing partners here.

    Research and validation Research and validation

      01 Climate change is altering the way that we experience events

      By 2050, over 1.3 million properties in Great Britain will be at risk of substantial flooding. Our data provide the right people with the correct information – so that they can mitigate risk.

      The UK Flood Map helps to quantify UK flood risk and asset exposure for 5 climate scenarios, across 3 time horizons. This is the first flood model in the UK to factor in the impact of climate change, rather than just relying solely on historic records. By doing so, Fathom takes the UK’s understanding of flood risk one step further and supports users to understand how risk will change over time.

      With new regulations requiring insurers, corporations, and risk managers to understand flood risk in the future better, our model provides accurate predictions for pluvial, fluvial, and coastal perils. Fathom-UK’s inclusion of 10 return periods means users have access to a comprehensive collection of event frequencies.

      The hydraulic model projects changing flood behaviour arising from UKCP18.

      Model validation Fathom-UK is validated against EA, Northern Ireland EA, Scottish Environment Protection Agency, and Natural Resources Wales flood data

      Comparison against a Fathom (blue) 1-in-100 year flood simulation of Reading to EA data (red). Comparison of our model has found that our work measures accurately against these data.

      Relevant research

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      Read more
      Research Paper

      A climate conditioned catastrophe risk model for UK flooding

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      Research Paper

      Assessing flooding impact to riverine bridges: an integrated analysis

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      Research Paper

      A simple inertial formulation of the shallow water equations for efficient two dimensional flood inundation modelling

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      Research Paper

      Distributed whole city water level measurements from the Carlisle 2005 urban flood event and comparison with hydraulic model simulations

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      Research Paper

      Evaluating the effect of scale in flood inundation modelling in urban environments

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      Research Paper

      Reach scale floodplain inundation dynamics observed using airborne Synthetic Aperture Radar imagery: data analysis and modelling