The Hitchhiker’s Guide to the Galaxy says 42 is the answer. But what is the question?


For Dr Alalea Kia it’s all about how new materials could be used to combat flooding.

Forget streets paved with gold. Dr Alalea Kia wants a world paved with Kiacrete. Why? Because Kiacrete – unlike concrete – is permeable. With the global cost of flooding projected to reach £500 billion by 2030, the high-strength, clogging resistant permeable pavement material – the result of her research – could be the answer.

“There has been a move towards sustainable drainage systems in the UK since the 2010 Flood and Water Management Act required them in new developments,” says Kia, a Royal Academy of Engineering Research Fellow in the UKCRIC Centre for Infrastructure Materials.

“But conventional permeable pavements, which have been around for the last 20 years or so, suffer from a range of problems. They lack sufficient strength and durability and they tend to clog up with debris and sediments. As a result, they require frequent and expensive maintenance.”

Kia spent the first three years of her PhD in the Materials section of the Department of Civil and Environmental Engineering studying these conventional systems, before concluding she could do better. “I realised we could alter the porous structure by engineering it such that the channels lead directly to the sub-surface. This stops stormwater build up, and the design allows the material to be stronger and more durable.”

The prototype Kiacrete has already been installed at Imperial’s White City Campus and now Kia, who set up her own company, Permia, anticipates going global. “There is interest from India, because Kiacrete not only absorbs stormwater but it also enables groundwater recharge.” She is also looking at the possibility of incorporating sustainable ground source energy into her pavement, “in order to develop climate change resilient pavements for our critical infrastructure.”

Kia’s new research project is looking at developing permeable infrastructure for heavy load bearing environments such as airports, focusing on developing a material that is sufficiently strong and durable for use in aprons, stands and taxiways. “Skidding causes half of post-1990 commercial aircraft crashes. I’d love to one day see permeable runways.” Sounds like Permia is ready for take-off.

Dr Alalea Kia (PhD Civil and Environmental Engineering 2019) was appointed as Royal Academy of Engineering Research Fellow in 2021. Her research interests include: urban flood mitigation and adaptation; sustainable drainage systems; permeable concrete pavements and their application in extreme weather and loading scenarios; multi-scale experimental and numerical modelling methods; and durability of cement-based materials. She is the founder of Permia, an Imperial spinout company.