Flood Risk Assessment Oxfordshire

Wilsham Consulting is based in Abingdon in Oxfordshire and has considerable experience of producing flood risk assessments and flood mitigation works for numerous sites across Oxfordshire for many years.

Indeed we visited many of the sites during the recent major flood events to see how accurate the reports were against the reality of the events.

Flooding is common across Oxfordshire, due to many settlements such as Henley, Wallingford, Abingdon and Oxford all being located at least partly on geological flood plain deposits. Flooding in Oxfordshire is really nothing new.

I read about the ” flood risk assessment oxfordshire ” campaign and want a professional FRA. What do I do?

Its great that the “flood risk assessment oxfordshire” campaign message is getting out. Perhaps you have been flooded and want to know how to mitigate the flooding? Told the EA does not have funding, or your flooding is not high priority? Perhaps you are looking to buy a property and concerned it may flood or you may have problems with insurance?

In any of these options, it it not enough just to look at some Environment Agency maps (but its a good start). Your house or business it as critical asset, to understand the risk and mitigate it is critical. We have a client who operated a Nursing Home which had £500,000 damage and was out of use for 6 months. That as following a 2 hr storm event. They were not even on any EA map as at risk (from surface, sea or watercourses).


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Flooding in Abingdon

In Abingdon there are large flood plains to the Eastern side which are essential to the protection of the town. These are what we consider examples of true flood plains – in that they flood every year and are absolutely essential to be allowed to flood to protect the town. Water must be allowed to flood these areas.

Unfortunately, rather confusingly the Environment Agency uses the term for areas which would only flood in events up to a 1:20 or 1:30 year event. We consider that this confusion between what the public and many engineers consider to be true operational flood plains and just areas which could potentially flood once or twice in a lifetime is not helpful. Wilsham have proposed to DEFRA and the EA that these terms be amended so they better reflect the actual risks and operations associated such locations.

Ironically, the recent flooding events in Abingdon largely related to the River Stert and River Ock and not the River Thames. Both of these smaller Rivers run directly through the town.  Both rivers suffer from the lack of pollution control or storm attenuation in relation to the A34 which drains to them. Likewise much of the North of Abingdon was constructed before the time in which effective sustainable drainage was enforced.

Most houses in Abingdon, and else ware that have flooded are not in a flood plain. The flood plain does not need to be rigid. Most flooding relates to artificial changes changes. For example the Ock channel had suffered for many years with a lack of maintenance, which resulted in a lack of capacity. This flooding far greater than that identified by the EA on based on geological flood plain deposits.

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Flooding in Oxford

Flooding in Oxford is common. Much of South Oxford in particular is identified as flooding and often does so.

However Oxford is a vibrant City and we have supported many clients in Oxford with flooding problems and flood risk assessments for Oxford Colleges to ensure that risks are understood and mitigated against, so far as reasonably possible.

So what is a Flood Risk Assessment?

A comprehensive professional engineering assessment of:

·         the various sources of flooding (not just EA maps)

·         the implications and

·         the mitigating measures

Consideration needs to be given in a flood risk assessment to the onsite and off-site implications of flooding. It requires considerable hydraulic knowledge, combined with practical civil engineering experience. Someone who spends all day producing flood risk assessment reports may be quick and efficient. The problem is – how often do they actually design drainage works and see sites that have flooded and the practical problems contractors need to deal with?

We our the founding members of “flood risk assessment Oxfordshire” – the campaign to raise awareness in the public of the importance of seeking professional flood risk help to raise understanding of the risk of flooding and the mitigating measures available. A key aim of “flood risk assessment Oxfordshire” is to raise awareness in the Environment Agency of the critical role civil engineering consultants play in designing flood relief or flood mitigation works across Oxfordshire.

Find out more about flooding in Oxfordshire from the Oxford Flood Alliance.

See our flood risk service to find out more.