Bhushan Tuladhar is an environmental engineer by training and the executive director of Sajha Yatayat, a public transport cooperative operating buses in and around Kathmandu. He is also chair of the NGOs Environment & Public Health Organization and Clean Energy Nepal, as well as an adviser to the United Nations Human Settlements Programme (UN-Habitat). 

DW: Nepal has been ranked as having the world's worst air quality. What do you think of thisYale air quality report?

Bhushan Tuladhar: The air quality situation in Nepal, in particular in the city of Kathmandu, is bad but I wouldn't say it's the worst in the world. But we are in the top 10% of worst cities in the world. The Yale University study looks outdoors and indoors. Indoors is where we face more problems, because around 70% of the houses in Nepal use traditional stoves with what we call solid biomass, which is firewood, agricultural residue or dung. The fuel is very contaminating and the stoves are not very efficient. Kitchens are the most polluted environment in Nepal.

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What are the main sources of outdoor air pollution?

The main source of pollution by far is transportation. The transportation system as a whole is not organized, with a lot of old polluting vehicles running on roads with a lot of dust.

The public transportation system is really inefficient and as a result we see a big increase in number of private vehicles. There are more and more trips made on private vehicles, particularly motorcycles. So the traditional way of mobility — walking, cycling — are going down steadily and right now only 27% of trips are made on public transportation, which is not enough.

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Road dust is visually more of a problem, but then if you look at the smoke, it's more of a problem from the health perspective. Because smog — like diesel smoke for example — has much finer particles, and also more toxic particles, it goes deeper into your lungs and causes problems like heart problems, cancer and so on.

The second issue is, there are certain industries such as brick kilns, which tend to operate in the winter when the pollution level is at its worst. There are about 100 of these around the valley. And the third is probably the burning of trash and agricultural residue.

How has the speed of Kathmandu's urbanization caused problems?

The first highway that connected Kathmandu to the Terai (in southern Nepal) came 60 to 65 years ago. Goods and services started coming in, physical development started coming in, tourism started coming in, industries started coming in. The way the government planned was Kathmandu-centric, so the industries were here, all the offices were here, all the hospitals, schools, everything was here. People who wanted employment and services would have to come to Kathmandu.

And while all of that was happening, they didn't realize that what made Kathmandu great was the way it was planned traditionally. Systems which had been in place for thousands of years to manage our natural resources, to manage our culture — a lot of that was destroyed.

What was the city like before this urbanization?

The traditional urban planners were some of the most brilliant people in the world. The way urbanism was planned in this valley, they realized the limits of natural resources. They were built as very compact settlements, with raw houses that helped conserve energy. They were compact settlements but with very large open spaces around courtyards. Courtyards also helped in bringing the community together, they helped to promote walking and cycling. And the open areas around the settlements were left for agricultural purposes.

They knew water was a limited commodity as well, so they had ponds collecting the rainwater, they had aqueducts transporting the water. It's a brilliant system from a technical point of view, from an environmental point of view and from a social point of view.

We lost a lot of that traditional system of water and land management. We rapidly jumped into the modern, Western culture and don't evaluate it properly. So what we see is the freeways of LA in Hollywood movies and we say, "Oh, we want some of that here in Kathmandu," without realizing that Kathmandu and LA are built very differently. But now we see cities like LA or New York going back to cycling and traditional transportation.

What can be done to make public transport greener?

In many countries, the government manages and subsidizes public transportation systems, so that it is affordable and it's efficient and so on. Here, the public transportation system is just left to the private sector, which operates its buses wherever they want, wherever they don't want.

Secondly, the government is promoting car-centred development. A great example of this is the ring road construction that is going on right now. It used to be a two-lane road with green belts on either side. Now it's being expanded to eight lanes with no trees, very small footpaths and nothing else. No cycle lane, no bus lane.

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We have been trying to convince the government that this is not the way you develop a city.

A street is a public space through which you experience a city. You go meet a friend on a street. There are people bringing business on a street. The festivals mainly happen on the streets. So that is how streets should be designed: for people and their activities. When you design for cars, people get left out.

This interview was conducted by Marco Panzetti and has been edited and condensed for clarity.