By AFP - Agence France Presse
Garbage roads: Nepal explores plastic paving
Cars speeding down a smooth, black street in Pokhara, Nepal, are also driving over piles of discarded plastic, which has been turned into an ingredient for road construction.
According to the World Bank, Nepal's urban areas generate around 5,000 tons of solid waste daily, 13% of which is plastic waste dumped in landfills.
While the recycling sector absorbs high-value plastics, such as bottles, low-value plastics, such as multi-layer packaging, pose a significant challenge because they don't fit into a single recycling category.
For a group of young Nepalese entrepreneurs, the vast accumulation of this low-value plastic waste represented an opportunity.
“A plastic road can use even low-value plastics,” said Bimal Bastola, founder of Green Road Waste Management, the organization leading the initiative in Nepal.
“We saw that there was room for these plastics to be used as a raw material, partially replacing bitumen in road construction.”
Discarded packets of noodles, cookies, and other snacks move along a conveyor belt in their waste sorting center.
The divided plastic is then put into machines to be shredded into fine pieces.
Since the early 2000s, neighboring India has led the world in building a network of plastic roads, even making it compulsory to use plastic waste on roads near major cities in 2015.
A growing number of countries are experimenting with this material, including neighboring Bhutan and Bangladesh.
In traditional road construction, bitumen is the binding material, a tarred oil product mixed directly with hot aggregates before paving a road.
The plastic road method, however, first coats the aggregates with crushed plastic before adding the bitumen.
“This method reduces the need for fresh raw materials, lowers costs, prevents water infiltration, and increases the road's lifespan,” said Bastola.
Studies show that roads paved with plastic waste can be twice as durable as normal roads.
Globally, only 9% of plastic waste is recycled, while 19% is incinerated and almost half ends up in controlled landfills, according to the Organization for Economic Cooperation and Development (OECD).
If left unchecked, the production of synthetic polymers - the building blocks of plastics - is expected to reach around 1.2 billion tons a year by 2060.
The plastic that accumulates in the environment is not biodegradable, takes hundreds of years to decompose, and breaks down into tiny microscopic particles.
Although Nepal has banned single-use plastic bags with a thickness of less than 40 microns, this ban is not strictly enforced.
For Bastola, increasing the construction of plastic roads is key to making the recycling of low-value plastics economically viable.
His organization says that around two tons of crushed plastic are used to build one kilometer of road.
So far, the organization has completed around 10 projects, totaling just over 1.5 kilometers (one mile).
“This is happening on a small scale, we need to scale it up,” said Bastola. “We have to do government-level projects and we're trying to work closely with the roads department.”
A pilot project is planned for this year in the capital, Kathmandu, at a major intersection.
“Nepal is interested in testing this technology through pilot projects,” said Arjun Nepal, an engineer at Kathmandu's roads department.
“But to take it forward, we need government-led standards to ensure quality.”
The World Bank says that life cycle analyses of plastic roads are limited and it is not yet clear what environmental impacts - if any - recycled plastics may have when used in road construction.
“While initial reports and pilot studies are promising, more research is needed to measure emissions during production, assess the release of microplastics over time, and determine how these roads behave when they are decommissioned,” said Valerie Hickey, global director of the World Bank's climate change group.
Despite these concerns, environmentalist Bhushan Tuladhar said that plastic roads represent an important opportunity for Nepal.
“This is an easy low-hanging fruit to address two problems simultaneously - the need for strong roads and plastic waste management - for a developing country like Nepal,” he said.
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