Digital insights improve flood resilience in Bangkok
We piloted a real-time stormwater flood forecasting system for Thailand’s capital that can accurately predict where and when flooding will occur in monsoon conditions. It’s the first of its kind in the world, made possible by combining our knowledge in flood risk management with our digital expertise and innovation.
Bangkok smart flood management decision support system
UK Foreign, Commonwealth & Development Office
Climate resilience, smart flood management, rainfall radar, hydraulic modelling, machine learning, data science, digital integration
Urbanisation is compounding the problem as green spaces and floodplains are lost to development, and expansion in hard surfacing exacerbates runoff. Drainage network capacity is being lost too, due to encroachment on canals, with rising population levels increasing the volumes of wastewater and solid waste.
Climate change will also increase the risks of stormwater flooding in Bangkok, as extreme rainfall events become more frequent and severe, while rising sea levels interfere with discharge from the drainage network.
Stormwater floods are tricky to predict
Intense, highly localised tropical rainstorms can occur with little warning, overwhelming Bangkok’s drainage network. Storms may last only an hour or two but can bring huge disruption and massive economic losses – not to mention the impact on public health and safety.
While Thailand’s capital also suffers river flooding from the Chao Phraya, this is easily forecast as the flood peak can be tracked as it travels downriver. By contrast, stormwater flooding from intense rainfall is challenging to predict.
“Unlike coastal or river flooding, which starts from a known source and propagates out from that location, stormwater flooding can occur nearly anywhere – particularly for localised tropical storms,” says Sharla McGavock, our principal hydrologist.
“We cannot simply use trigger levels based on level or flow gauge data because this doesn’t capture the spatial variability of stormwater flooding, and the lead time is not long enough to prepare for a flood event.”
Unlike coastal or river flooding, which starts from a known source and propagates out from that location, stormwater flooding can occur nearly anywhere.”
Sharla McGavock, principal hydrologist, Mott MacDonald