Waste Plastic & Tyres to Build Better & More Durable Roads

As per Central government rules in India, sale of plastic material for storing, packing and selling tobacco products is banned. No food stuff should be packed in recycled or compostable plastic and recycled plastic carry bags should carry Bureau of Indian Standard specifications. But cheap poly bags are being circulated fearlessly in markets despite the ban imposed.

In its recent submission to the Supreme Court of India, the Central Pollution Control Board said four metros, including Chennai (419.4 tonnes a day) were the major plastic waste generators in the country. About 40% of this waste is not recycled. They do not undergo bio-decomposition. Hence, they are either land filled or incinerated. Both are not ecofriendly processes as they pollute the land and the air. A lot of it is also littered on roadside or ends up choking the waterbodies.

It is a known fact that waste generated from discarded plastic items is hazardous to the environment, but what is seldom known is that waste plastic can also be utilised in constructing roads in the city. The household plastic waste can be mixed with asphalt for blacktopping of the roads which is a great way to get rid of the plastic waste, decreasing the raw material cost and enhancing the durability of the road laid.

This move has been carried out in India with the advocacy of Central Pollution Control Board (CPCB) to prevent the persistent problem of potholes on the roads and to increase the resistance to water at a lower construction cost.

Apart from making use of the enormous plastic waste that is churned out on a daily basis, these roads are expected to be a lot smoother than ordinary cemented roads. Plastic-cum-tar roads is 25 per cent better than unmodified roads and is almost 200 per cent resistant to soaking up water. The maintenance cost of the road is very low, while its durability is high. The roads reportedly need no repairing for at least five years. This is done by integrating plastic with tar known as polymer-modified bitumen, thus making good use of discarded plastic and preventing further damage to the environment.

Some other cities in the country have rubberized roads, made of used rubber tyres that result in better grip to prevent skidding. Waste tyres in India are categorized as solid waste or hazardous waste. It is estimated that about 60% of (retreaded) waste tyres are disposed via unknown routes in the urban as well as rural areas. The hazards of waste tyres include- air pollution associated with open burning of tyres (particulates, odour, visual impacts, and other harmful contaminants such as polycyclic aromatic hydrocarbon, dioxin, furans and oxides of nitrogen), aesthetic pollution caused by waste tyre stockpiles and illegal waste tyre collecting and other impacts such as alterations in hydrological regimes when gullies and watercourses become waste sites.

All in all this is a great move by the Indian authorities in the right direction of utilizing waste in a smart manner which should be implemented worldwide.