With the risk of flooding in the UK always increasing, implementing Sustainable Urban Drainage Solutions (SuDS) is now a vital consideration when building new developments, helping to reduce flood risk to homeowners. Here we discuss the role of SuDs including those with geosynthetic materials, as part of new housing specification.

As a result of the COVID-19 pandemic, the start of 2020 feels a long time ago. However, if you cast your mind back to the start of the year, you will remember how the UK was rocked by two extreme windstorms: Ciara and Dennis. Together, the pair of storms, which happened just a week apart, caused around £425 million worth of damage, affecting homes, cars and businesses. The majority of this damage was caused by bouts of intense flooding, which affected a number of the nation’s most important rivers. Now, with the country still looking to rebuild following the flood damage, experts are warning that such extreme weather is likely to become more common in the near future. In fact, the UN Intergovernmental Panel on Climate Change (IPCC) has warned that the UK is “very likely” to see more heavy rainfall events by the end of the century.

Unfortunately, many would say that the IPCC’s predictions are already coming true. Since 2007, the UK has suffered a major flooding incident every year, affecting around 100,000 properties in the process. Additionally, the Met Office recently discovered that the maximum daily rainwater volume experienced across the country has risen by 17%, from 64mm to 75mm in the last half century. To this end, experts such as Dr Mohammad Heidarzadeh, the Head of Coastal Engineering and Resilience at Brunel University, now believe the nation’s interval for major floods has dramatically shortened. According to Dr Heidarzadeh: “the interval for major floods was fifteen to twenty years in the past century, it has shortened to two to five years in the past decade.”

In addition, findings from the 2017 UK Climate Change Risk Assessment suggested that sea levels in Britain could rise by around 80cm by 2100. As a result, one in 10 new homes in England is now built on land that’s deemed to be a ‘high' flood risk.

Clearly, governments on both a local and national level must look for practical and implementable solutions. As such, this will require those in charge to move on from existing approaches to flood defence. Primarily, the sole tactic of adapting buildings in coastal communities and upgrading coastal defences must now evolve, especially as sea levels rise.

Therefore, implementing SuDS must become an even more vital component when building new developments. Such schemes work to slow water down before it enters a river, increasing the area in which water can naturally drain. As such, SuDS schemes can help to reduce the frequency and/or severity of flooding events. What’s more, as SuDS schemes mimic natural drainage as closely as possible, they provide an opportunity to combine effective water management with green space creation - providing benefits for amenity, recreation and wildlife.

The government has already recognised how effective these systems can be in the battle against flooding in the Flood and Water Management Act of 2010. The wide-ranging document required the inclusion of sustainable drainage of surface water in construction projects at risk of flooding. Additionally, it removed the automatic right to connect to public sewers and instead gave powers to local authorities to approve new drainage systems, such as SuDS and their connection to public sewers.

At Keyline Civils Specialist we offer a wide range of SuDS schemes, including some manufactured from geosynthetic material. Whilst geosynthetic solutions have been around since the 1970’s, in recent years, they have become more technologically advanced. To this end, it’s important that those specifying these systems understand what’s now available on the market.

Currently, geosynthetic solutions can be used to control erosion on cut slopes, as well as to provide roadside drainage. When it comes to selection suppliers offer a broad range of solutions. From technology which comprises of two grades of thick plastic grass reinforcement mesh and is suitable for use on overflow grass car parks, to heavy-duty, recycled plastic solutions that ensures even higher levels of reinforcement.

Alternatively, we are able to supply geosynthetic solutions which offer users a thermally bonded, nonwoven geotextile membrane that works as a filter, optimising the cleansing of water entering a permeable paving attenuation system. The innovative geotextile is manufactured with microbial biomass, which eats and degrades oil in the water it soaks up. In turn, when it rains again the microbial biomass is quickly re-established. This can provide a significant improvement when compared to previous flood defence systems, which would become more damaged year-on-year, affecting their viability.

With a network of branches around the UK and an experienced team in place, we can help fulfil the requirements of a SuDS scheme – no matter its scale or size. For more information, please visit: https://www.keyline.co.uk