Kolkata authorities have begun modifying freshly painted rainbow roads and restricting two-wheeler movement on one flyover after social media posts purportedly showed bikers skidding during rain, triggering a road-safety controversy just days before Durga Puja.
The Kolkata Metropolitan Development Authority (KMDA) installed anti-skid reflective road studs and reflective buttons on the flyovers, while police announced additional precautions on the Chingrighata flyover during wet weather. Mechanical sweepers were also deployed to abrade painted surfaces and improve tyre grip.
The action followed criticism from bikers and motorists after posts circulated online showing multiple two-wheelers apparently losing control on the rainbow-painted Chingrighata flyover after Wednesday’s rain. Police Commissioner Ajay Nand said the circumstances of the incidents had not been established because officers had not obtained CCTV footage.
“We are not sure how the incident took place as no CCTV footage is available,” Nand told the Times of India. He said police had issued cautionary boards and would regulate bikers from using the flyover when it rains. He also cautioned people against using the road for making social media reels.
The state’s Urban Development and Municipal Affairs minister, Agnimitra Paul, who had overseen the pre-Puja road-painting drive, initially said the material used was anti-skid. “Apparently, there is no chance for vehicles to skid. The painting has been done to keep up with the mood of the festive season and it is not a permanent feature. The colour will naturally wither away with time,” she told the Times of India on Wednesday.
As the criticism mounted, Paul said the cause of the skidding incidents needed to be investigated and that road-user safety remained the priority. She said agencies would examine the matter and take necessary action.
Road and civil engineers questioned whether the painted surfaces had undergone friction testing, particularly for wet-weather conditions. A Public Works Department engineer cited Indian road-marking requirements, including IRC:35 and specifications issued by the Union Ministry of Road Transport and Highways. According to the engineer, urban road-marking guidelines call for an initial British Pendulum Number of 55 and a minimum threshold of 45.
Engineers also said conventional thermoplastic road-marking material was not intended to coat an entire carriageway. Large decorative surfaces, they said, require specialised coloured surfacing systems and independent skid-resistance assessments. A road engineer told the Times of India that ordinary oil-based or household emulsion paints should not be used on trafficked roads unless they are specifically engineered and certified for that purpose.
The Kolkata Municipal Corporation brought its roads and civil engineering departments into the corrective work. A KMC official said mechanical sweepers had been used on the Gariahat flyover to roughen the surface and reduce the risk of vehicles slipping. “We are keeping a watch on the situation and may need to intervene at any point to avert accidents in future,” the official said.
A senior civic official associated with the exercise said the type and quality of paint would undergo technical scrutiny before approval for use on road surfaces in future. KMDA officials were directed to undertake similar corrective measures on the Chingrighata flyover.
Traffic officers at the Beliaghata Traffic Guard said speed monitoring had been intensified on Chingrighata flyover. Motorists exceeding the prescribed speed limit would face prosecution, while entry onto the flyover would be staggered after rain to prevent bikers from getting an open stretch on which to race.
Nand said no comparable restrictions had been imposed on the other two rainbow-painted stretches, the Gariahat flyover and Red Road, because they were operating normally. The Chingrighata restrictions and surface modifications will remain subject to monitoring by the police and civic agencies.
