Mumbai’s ‘melody road’ faces the music: A look at the science and history of musical roads

“On a high-speed arterial road, any auditory distraction is a matter of concern. Drivers are slowing down unexpectedly or becoming distracted, which poses avoidable safety risks,” read a part of the letter.

While local residents have called for civic intervention into the matter, musical roads have been implemented successfully across the world over the past 25 years. We explain.

What is the science behind a ‘musical road’?

The concept of a musical road entails specially engineered roads where music is generated through grooves embedded into the road surface. When vehicles drive past the precisely designed ribs at a constant speed, the road produces a musical tune. 

The variation in tune generated from the grooves is determined by the spacing and width of each of the ribs. If the ribs are constructed closely, it produces higher notes while wider spacing creates lower tones.

When vehicles roll past the ribs, the friction against wheels generates vibrations which transmits through the wheels to the car body. Since each rib is laid out to correspond to a particular pitch, it corresponds to a certain frequency and the melody is experienced optimally when vehicles maintain the speed limit. According to experts, environmental factors ranging from wind conditions, vegetation, and nearby structures play a crucial role in ensuring the clarity of sound generated. Careful analysis of the surroundings is also crucial to minimise interference from external noise.

A global history

The history of musical roads goes back to 1995 when two Danish artists — Steen Krarup Jensen and Jakob Freud-Magnus — invented the “asphaltophone” (musical road) through specifically designed road surface topology in Denmark.

However, it was over a decade later in Japan that the concept of musical roads took shape and burst to popularity. In 2007, Japanese engineer Shizuo Shinoda accidentally discovered that rumblings in the road generated music while he was working with a bulldozer.

Soon, the idea of musical roads was implemented across over 30 stretches in Japan where the idea was not only to entertain but also to encourage road safety and prevent drivers from dozing off.

In recent years, such musical roads have been implemented across the world including in countries like South Korea, Hungary, Taiwan, UAE, and the US, amongst others.

While most stretches are developed in sparsely populated areas, there have been instances in the past where a musical road was relocated owing to a disturbance including in the US. According to records from the Lancaster Museum of Arts and History in California, a musical road on Lancaster’s Avenue K — which was developed in 2008 — was re-paved and moved to a more secluded Avenue G after concerns of noise pollution as far as a half mile came to fore.

When the music came to India

The musical stretch along the Coastal Road, built at a cost of Rs 6.21 crore, marks India’s first foray into the technology. Jointly developed by Routes Worldwide India in collaboration with UTKOPRO Kft., Budapest, Hungary, the project was implemented by BMC along with a team of 6-7 Hungarian technical experts.

During the construction of Mumbai’s ‘musical road’. Photo: Courtesy of BMC

The idea was first mooted by Shiv Sena leader and former Mumbai South Central MP Rahul Shewale. On why the Coastal Road was chosen for the project, BMC officials said, “The technology demands the road surface is smooth and traffic free. In Mumbai, most roads are congested and also, it would be difficult to dig up roads for the same. Coastal Road is a stretch that allows for constant 60-80 kmph travel speed so it made sense to implement the concept here.”

The officials said the musical grooves have been designed to ensure weather resistance, durability as well as long term performance. The primary motivation, they said, is to “introduce joy, engagement and cultural pride” into everyday travel. Further, the BMC is aiming for this to attract tourists.