India’s richest and most populous city, Mumbai, has announced that it will be converting 400 km (250 mi) of its major roads, including shoulders, from asphalt to concrete, the largest such change of pavement type to have ever been done in India, according to The Times of India. The Brihanmumbai Municipal Corporation (BMC), which runs the city of over 17 million residents, announced the move in a bid to permanently end the city’s problems with potholes, which especially become a problem in the very wet monsoon season (usually June – August), when the city receives most of its annual rainfall and experiences regular flooding. The city spends millions every year to fix and maintain its potholed asphalt roads, and expects the concrete roads to have much lower maintenance costs despite the high initial costs. The project is estimated to cost ₹60 billion (about US$750 million), making it the single largest road construction project ever awarded by the BMC.
Moreover, Iqbal Chahal, the Municipal Commissioner of the BMC, said that a contract for further converting another 375 km (230 mi) of city roads from asphalt to concrete would be also be put out to bid in March of this year. With that, all 2,000 km (1,250 mi) of Mumbai’s major roads would be made of concrete. These contracts however, come with some very strict terms for the contractors. Interestingly, only companies with experience in construction national highways in India have been allowed to bid. This is because city roads in India, like most of the world, are usually made of asphalt, and so the only contractors with experience in constructing concrete roads are those that work on national highways.
India is also currently building the Delhi-Mumbai Expressway, which will be India’s longest expressway at a length of 1,350 km (835 mi) and will be made entirely of concrete.
To ensure that contractors do not subcontract their work out to other contractors who lack experience with concrete roads, the contract bars contractors from subcontracting most items. In addition to building the roads, the contractors are also expected to maintain them for 10 years. A full-time quality management monitoring assurance agency (QMA) has been appointed by the civic administration to oversee the road construction. When purchasing the material, QMA and BMC officials would be deployed at various plants and material sources to assure proper quality as and when required. The entire construction is expected to take 2 years.