Flooding costs the UK £2.2 billion annually and is projected to cost £27 billion by 2080 without significant flood resilient infrastructure investment. Climate change is predicted to increase the likelihood of major storm events by 59%. It is therefore critical to develop climate change resilient permeable infrastructure, such as permeable pavements, to alleviate the negative impacts of flooding.
Permeable concrete pavements are one of the most promising mitigation strategies used to stormwater through otherwise impermeable infrastructure. Conventional permeable pavements are, however, prone to clogging by debris that are trapped within the pore network, blocking the pavement and reducing its drainage capacity. Most importantly, the insufficent strength, durability and regular clogging of conventional permeable pavements requires frequent maintenance. This degrades perfomance and ultimately means they are not a suitable solution.
Researchers at Imperial College London have developed a next-generation clogging resistant permeable pavement (also known as Kiacrete) that overcomes the conventional permeable systems’ limitations. Kiacrete’s engineered uniform pore structure addresses urban flooding and climate change through stormwater management and groundwater recharge. The novelty of Kiacrete, compared with conventional permeable pavements, is its: i) higher permeability (ten times greater); ii) superior clogging resistance, despite extensive exposure to stormwater sediments; iii) improved compressive strength (twice as strong) and iv) enhanced durability performance.
The key innovation that leads to Kiacrete’s excellent drainage performance is the channels cast within it, which addresses the clogging associated with conventional permeable pavement’s indirect pore network. Furthermore, the cementitious material poured around these direct channels can be tailored depending on the specific application.
After proving the performance of Kiacrete in the laboratory, the team have developed a novel patented interlocking tile system to deliver cast in-situ Kiacrete at a commercial scale. The long-term goal is to develop the first climate change resilient permeable infrastructure that will have the potential to be widely adopted both in the UK and internationally.