Professor Afonso Virgiliis, is not washing his university’s parking lot… he’s demonstrating his permeable pavement technology, designed to soak up flood waters and keep roads open and safe during tropical downpours.
In Brazil, such downpours are occurring with increasing frequency. But Professor Virgiliis says his system can mitigate their impact. Unlike conventional pavement which is designed to repel water, his version absorbs it.
“It is composed of a permeable coating and a series of granular layers that have stones of different sizes. What happens is that when the rain falls over this coating, this coating allows the water to flow down through it and the water is stored in the empty spaces that exist between these stones,” says Virgiliis.
When the rain stops, the water trapped in the pavement drains away.
Successful traffic endurance tests in the lab have persuaded Sao Paulo’s government to announce field trials for the pavement in areas where traffic is light later this year.
Because of its porous nature, the pavement is not recommended for roads with a high volume of heavy traffic – at least, not yet.
Virgiliis said, “Our main expectation for the future is to develop a type of pavement that can endure heavier traffic and this depends, of course, on a bigger technological investment and more research.”
The pavement’s other disadvantage is cost. Like other porous asphalts, it’s 30% more expensive than conventional paving materials but while flooding causes millions of dollars in damage every year, Professor Virgiliis believes it may be a price worth paying.
Bottom line: Brazilian researchers have developed a new type of permeable pavement that can store rain water and ease the impacts of floods. They say the pavement could save lives and money in flood-prone countries around the world.