SOLID's Flood Mitigation

Flood Risk in the UK

The country breathed a sigh of relief last week as rain clouds dispersed and water levels were given the opportunity to subside. However, with storms still forecast and Summer a long way off, and even then, no guarantee of sunshine, those in the worst hit areas continue to brace themselves for further flooding. We are therefore, forced to consider the likelihood of further storms and what can be done to prevent the level of damage we have recently seen.

We were once able to describe storm scenarios in terms of years for example a ‘one in a thousand-year event’ or a ‘one in thirty-year event’ - determining the likelihood of catastrophic storms occurring. Probabilities such as these have been misleading. The common assumption to make is that a ‘one in a thousand’ year event describes the size of a storm that is only possible once every thousand years, or that there will be a thousand years between each storm of this size. In reality ‘one in a thousand years’ simply equates to the probability that there is a 0.0001 chance of a large storm occurring in any year (or 0.10%). The chance may be small, but it could still happen. Unfortunately, with climate change so prevalent, epic storms, which see a month’s worth of rainfall land in a matter of hours, are becoming increasingly common. 

SOLID’s Flood Mitigation

Our civil engineers have been visiting various sites since the New Year to determine flooding solutions to properties within floodplains and flood mitigation for new developments. Some of the tasks performed by the SOLID team include -

  • Catchment flood modelling to accurately quantify the volume of flood water as well as to predict the route that the water will take and where the localised flooding will occur. The purpose of this is to inform the client/council of the severity of the flooding. It opens a dialogue in which the correct design solutions can be established and a realistic budget can be agreed upon to mitigate the flooding. Evacuation and emergency plans can also be informed by these complex hydrologic and hydraulic modelling. (Our FRA and drainage strategy plans).

  • Designing appropriate infrastructure which mitigates flooding. This includes the incorporation of SuDs and other infrastructure such as piped networks, attenuation tanks, culverts and weirs. An important component of mitigating flood risks is combining the above mentioned infrastructure to work as a continuous system with the various components each playing a role in controlling flows. (Our detailed and development design phase)

  • Advice on maintenance of existing infrastructure and the implementation of the approved maintenance plans. This becomes a critical part of flood mitigation as it enables the infrastructure to work effectively as per the design. (Part of our construction design)

Civil Engineering for Flood Management

We asked one of our engineers, Sebastian Rogalski, what he has noticed most from his recent site visits, he replied - 

“One of the most noticed issues on recent site visits has been a lack of infrastructure maintenance, which has caused the systems to completely fail or has increased the severity of the flooding. More needs to be done to ensure that consistent maintenance is carried out on the stormwater infrastructure. Moving forward, further in-depth planning consideration should be given to building in flood plains, and infrastructure design should be able to accommodate more severe storms.  Further dialogue with farmers also needs to be made to secure additional land where controlled flooding can occur and ensure that after the water subsides the farms are not damaged and can operate soon after.”

If you have been affected by flooding during the recent storms, do contact our SOLID team to arrange a site visit and flood mitigation assistance.