Engineers from the University of South Australia believe that permeable pavements specifically crafted for local rainfall and soil conditions could be utilized in community and infrastructure settings to reduce the impact of flooding, based on the results of a new study.

Permeable pavement is not a new concept. Indeed, it’s already in use on many driveways, parking lots, and some roads and usually consists of “permeable pavers laid on an upper bedding layer of between 2-6 millimeters of gravel under which lies a base course layer above natural soil,” according to the University of South Australia. They are constructed to allow rainfall to pass through their surface, store water in the base for later reuse, and reduce urban flooding by up to 50 percent. But their success in current forms is variable, depending on rainfall intensity, soil type, and pavement thickness.

To determine the optimal permeable pavement system, the researchers built an algorithm and input data from 107 towns across Australia, allowing them to estimate which combination of soil type, rainfall levels, and pavement thickness yield the most reduction in flooding. The results demonstrate the pavement type is heavily dependent on local conditions. “Our study shows that this is possible if the base course layer in permeable pavements is suitable for local conditions, taking into account the soil type and rainfall intensity,” says Mizanur Rahman, a professor of engineering at the University of South Australia. “The pavement needs to be thicker if the rainfall intensity is higher or the soil is less permeable. For highly permeable soils, the amount of rainfall is less significant.” Utilities could work with their colleagues in the transportation sector to encourage the construction of permeable pavement, which Professor Rahman says would markedly reduce stormwater loads and reduce flooding. Access the full study here or read a relevant news article.