Flood-risk data under the microscope

Motion Director, Neil Jaques, discusses why access to real-time intelligence may not be the answer for tight planning application deadlines.

Timescales for flood risk assessments are often critical for the developer.  In order to meet expectations, obtaining and analysing flood information has to be completed as quickly as possible.  Against these challenges, is access to real-time data justified?

Obtaining reliable flood data and carrying out the necessary analysis can be hampered by the uncertainty caused by varying approaches to modelling in different parts of the country.  There is no standard format for provision of flood information across the Environment Agency’s regions.  A 21-day wait for Product 4 data – which can include detailed flood-risk assessment mapping, flood zones, defence and storage areas, as well as historic flood event outlines – can be a major obstacle for the developer.

Moreover, Product 4 data requests do not always generate information consistent with what is freely available online.  If what comes back is not particularly helpful to the flood-risk engineer, further delays to the planning application process could be inevitable.  This could be compounded by the costs involved for completion of any additional reports.

A large number of watercourses run across the UK that range vastly in size and scale, and many have not been modelled.  Some sites still require the detailed modelling and local assessments which add time and money to a project.  Interpretation based on historic flooding is not always accurate or possible.

Intelligent application of data

The article by Jack Heslop, ‘How greater use of data can enable better flood risk management’ (New Civil Engineer, August 2022) was therefore of particular interest as it makes the case for publishing data online for planners to carry out their own interpretation.  A one-stop-shop approach to flood-risk management via a local government digital tool is an attractive proposition.  Faster access to data would undoubtedly benefit planners and developers and could be a step in the right direction.

However, planners often need to cover a range of topics.  In addition to specialist skills, the critical analysis is the additional value that independent consultants can bring to the table, challenging the data when we believe it is incorrect.  Within the realm of hydraulic modelling, there is a difference between data and intelligence.  A professional with appropriate skills and training can understand information and harness it for effective decision making.  An engineer can also look at data and pinpoint the underlying issues behind the figures.

While dynamic access to flood information sounds compelling, in practice the problem would arise when assessing a whole catchment area.  Here, the sheer size of the data set would make it virtually unmanageable.

All of these considerations mean we are still a long way off from clear and easily accessible information for planners.  Until such time when we have a uniform approach to the detail, quality and the provision of data, the complexities of flood management need to be tackled at the earliest stage possible.  For the sake of a 30-minute consultation with an expert, my initial advice is don’t leave flood risk to the last minute.

If you would value a preliminary discussion about the water management issues associated with your development project, email njaques@motion.co.uk or call 01483 531300.