Ill-designed structures seldom slow down traffic

CHENNAI: Urban transport planners describe Chennai’s roundabouts as “circles without purpose”. As per the Indian Roads Congress, an intersection with four or more arms that witnesses peak-hour traffic between 500 and 3,000 passenger car units (PCUs) ought to be managed by a roundabout. In Chennai, this holds true for very few junctions as most carry more than 3,000 PCUs during peak hours leading to congestion and accidents.


“The problem is with the design of a roundabout. A proper roundabout would force vehicles to slowdown at the entry with the help of speed breakers. This allows more time and space for other vehicles that are already in the roundabout to proceed further,” said Advait Jani, urban transport planning expert.

Jani cited the example of the roundabouts on grade separators at Padi and Pallavaram. “Y-shaped medians would prevent vehicles from taking a right turn cutting inside the roundabout,” he said.

Often, policemen considering roundabouts as an obstruction instead of a traffic management solution contribute to the mess. At the Anna Nagar roundabout, where the 2nd Avenue and 3rd Avenue converge, traffic police ask motorists to cut inside the roundabout to ease congestion. After a point, this becomes a habit for road users.

Urban planner K P Subramanian said unless inefficient driving was pulled up, the situation was unlikely to improve. “Very few cases where inefficiency of the driver has been cited as a reason for an accident. Only when that is established can the RTO be pulled up for allowing such drivers on the road,” he said.