Following a few spells of rain, potholes, the bane of all commuters, have once again started appearing on the city’s tar and asphalt roads. To understand why this phenomenon is unfailingly witnessed every monsoon season, mid-day turned to experts, who said craters primarily form due to water infiltration through cracks or poor drainage.

An Eastern Express Highway stretch near Priyadarshini junction in Sion East yesterday

Professor Manoranjan Parida, director, Central Road Research Institute (CSIR), said potholes primarily form due to water infiltration through cracks or poor drainage, which weakens the pavement structure. “Factors such as traffic loading, ageing of bitumen, poor construction practices, and pre-existing cracks further accelerate the deterioration. Improper implementation of the job mix formula [detailed recipe for creating a specific construction mixture] — such as insufficient binder content and poor-quality aggregates — also contributes to pothole formation,” he said.

An internal road near MMRDA Grounds, BKC