Kolkata’s rainbow flyovers have turned a pre-Durga Puja beautification drive into a road-safety debate. A viral dashcam video appears to show three bikers skidding on the colourfully painted Chingrighata flyover, while opposition leaders have questioned whether glossy paint applied across vehicle-running surfaces can reduce traction during rain. The Indian Express said it could not independently verify the video’s authenticity, but the controversy has exposed a larger question: when public roads are redesigned for visual impact, what technical and administrative checks ensure that the carriageway remains safe?
The painting is part of a wider effort to decorate Kolkata ahead of the first Durga Puja after the BJP came to power in West Bengal, according to the report. Flyovers at Gariahat and Chingrighata have been painted in bright colours, while the Howrah Bridge has been decorated with lights. Urban Development Minister Paul has been leading the road-painting drive and was seen drawing an alpana at the Park Circus seven-point crossing. The minister also shared a video from a coloured flyover in Gariahat and described the work as representing “the road of trust, love and brotherhood”.
The immediate dispute is not about whether cities should be attractive. It is about whether decorative treatment has been applied to parts of the road used directly by vehicle tyres, and whether the material used for that purpose has the friction, adhesion, visibility and durability required for a high-speed urban structure.
A letter from Ashutosh Chatterjee, general secretary of the Congress’s West Bengal unit, to Paul and Smita Pandey, commissioner and administrator of the Kolkata Municipal Corporation, specifically raised this concern. Chatterjee wrote that “glossy paint on roads intended for motor vehicle traffic is dangerous and should not be permitted”. He argued that ordinary household paint should not be used across the carriageway and referred to IRC:35-2015 and IS:164 in discussing road markings and their technical requirements.
The letter cited a potential reduction in the coefficient of friction when a glossy surface is wet with water, oil or diesel. According to the figures quoted in the report, friction could fall from 0.6–0.7 to below 0.3. Chatterjee said this could cause two-wheelers and cars to skid. The concern is especially relevant on flyovers, where road users have limited space to recover from a loss of control and where two-wheelers are more exposed to changes in surface grip.
Somendra Mohan Ghosh, an environmentalist and green technologist quoted by The Indian Express, said that ordinary paint of different shades appeared to have been used instead of thermoplastic paint and that such paint did not contain anti-skid materials. This is an assessment attributed to Ghosh; the supplied report does not include an official technical inspection, laboratory test or municipal specification confirming the material used on the flyovers.
That distinction matters. The viral footage may have prompted the public debate, but it does not by itself establish why the bikers fell. The report says the footage appeared to be dashcam video and that its authenticity could not be verified. It also records a claim by the Trinamool Congress that the freshly painted flyover had become a “death trap” and that accidents had occurred during the first spell of rain. Those statements are political claims, not an independently verified accident record.
The stronger public-interest issue is therefore the absence, in the supplied material, of a clear technical account from the agencies responsible for the work. The report does not state which contractor carried out the painting, what product was specified, whether the surface was tested before opening to traffic, or whether the work was limited to non-traffic areas. It also does not provide a police accident register, a road-safety audit or an engineering assessment linking the reported skids to the paint.
Those missing details point to the institutional chain that governs seemingly simple beautification projects. A road surface is not merely a canvas. Decisions about its treatment involve the public works or municipal authority, the agency managing the structure, the contractor applying the material and officials responsible for traffic safety. Each should be able to establish what was applied, where it was applied, how it performs when wet and who authorised the work.
The references to IRC:35-2015 and IS:164 in Chatterjee’s letter also frame the issue as one of standards rather than aesthetics. Road markings and traffic-surface treatments must serve operational purposes, including visibility, durability and adequate interaction with tyres. The letter said conventional oil paint lacked glass beads and could be difficult to see at night or in rain. The report does not establish whether the coloured treatment on the Kolkata flyovers was intended as road marking, decorative surfacing or a separate coating, but that classification has practical consequences for the applicable specifications and testing regime.
The Kolkata controversy also illustrates why public infrastructure projects need a visible safety record even when they are presented as civic decoration. The work is being carried out in prominent locations and before a major public festival, when traffic volumes, visitor movement and public attention are likely to be high. The minister’s public statements emphasise the symbolic and civic purpose of the colours. The safety question requires a different kind of communication: material specifications, friction results, maintenance responsibility and the steps taken if the surface becomes hazardous.
At the ground level, the risk is unevenly distributed. A driver in a car may have some protection during a skid, while a motorcyclist can lose control with little warning. Rain, oil or diesel on the road can alter the interaction between tyres and the surface. On a flyover, a slippery patch can affect not only the rider who encounters it but also vehicles travelling behind or alongside. The supplied report does not quantify injuries or crashes, so the scale of any actual harm remains unestablished. But the possible consequences explain why road-surface decisions require more than visual approval.
The episode further raises a procurement and accountability question. If a public agency chooses ordinary paint for a traffic-bearing surface, the decision should be traceable to a written specification and an approving authority. If a specialised anti-skid coating was used, the authority should be able to demonstrate that it was installed correctly and remains effective in wet conditions. If the coloured treatment covers only areas outside tyre paths, that should also be clear from the project design. Without such documentation, citizens are left to judge infrastructure safety through viral videos and political accusations.
The report records that Paul has invited people to see the painted sites and said that additional alponas could be painted at Rashbehari and Park Street if time permitted. It also records the Congress letter and the Trinamool Congress’s criticism. What is not yet supplied is an official response addressing the specific engineering concerns. That response is the next important piece of the story—not because it will settle a political contest, but because it can clarify whether the city’s decorative road treatments meet the technical conditions expected of public infrastructure.
Kolkata’s rainbow flyovers have therefore become a test of how urban governments balance civic presentation with operational safety. The available evidence confirms a public controversy, a formal warning about surface friction and an official beautification programme. It does not yet confirm that the paint caused the skids shown in the video, establish the number of accidents or identify the exact material used. Those facts should be established through technical inspection, documented specifications and verified accident data before responsibility is assigned. Until then, the central lesson is clear: a road can be visually transformed only after its safety function has been protected.
