In line with the government's "Waste to Wealth" initiative and to promote the construction of environmentally friendly national highways, the NHAI has begun a trial use of "Steel Slag" in road construction. With the help of this project, the problem of a lack of materials for the construction of the National Highways will be addressed. Waste from the steel industry can be used instead of natural aggregates such as sand, gravel or crushed stone.

NHAI began testing steel slag's potential for use in road construction with the goal of creating India's first Pavement Quality Concrete (PQC) with it. The authority approved the construction of a one-kilometre trial patch by Central Road Research Institute (CRRI) for the Panvel-Indapur portion of NH 66 near Bombay, where steel slag-derived aggregates were used in place of 100% natural aggregates. The trial's findings have been favourable. The road built using steel slag is an illustration of how waste may be turned into wealth.

The NHAI has promoted the innovative use of new alternative materials, such as the use of plastic waste, building and construction waste, etc. The use of such materials in road construction will reduce construction costs and promote resource efficiency and the circular economy.