Air pollution control measures for Kathmandu Valley

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Air pollution is a dominant problem in the Kathmandu Valley in recent days. Numbeo database services listed Kathmandu as the third most polluted city (pollution index-95.76) around the world in early 2017.  Air pollution usually occurs due to greenhouse gas (GHG) emissions, particulate matters (PM10, PM2.5), and Ozone (O3). However, the recent study revealed that 69 % of air pollution occurs due to the traffic in Kathmandu Valley. Traffic and construction works produce a lot of particulate matters (PM), a major pollutant in this area. PM is a collection of different small particles in the air such as dust and mineral particles, black carbon (BC), ammonium sulphates, ammonium nitrates, organic carbon, and fly ash. BC is responsible for cancer as well as lungs and heart diseases. PM in Kathmandu comes from various sources such as buildings, roads, and sewer construction, brick kilns, smoke-belching diesel engines (eg vehicles and diesel-generators), kerosene-using cooking stoves, and burning of solid wastes in the open air. According to a news report (Himalayan Times, March 2016), a two-hour average PM10 level was 781 µg/m3 and PM2.5 level of 260 µg/m3 in Putalisadak, Kathmandu. The World Health Organization (WHO) guideline prescribes 24-hour mean of 25 µg/m3 for PM2.5 is and 50 µg/m3 for PM10.

According to the World Air Quality Index website, Air quality index of Ratnapark, Kathmandu was 158 on April 22 which is unhealthy. This means children and people with respiratory diseases should avoid outdoor exertion at this pollution level. If this quantity increases to more than 300, air quality level is considered as hazardous which means everyone should avoid outdoor exertion. This also means that if the pollution level is increasing steadily, that day is not so far when everyone will be warned to stay indoors, and all outdoor activities get affected. Due to lack of transparent emission inventories, exact emissions data are not available.

Air quality in Kathmandu is getting worse by the day, but the government does not seem to be so active to envision proper strategies to control air pollution in this area. Lack of proper monitoring of air pollution is also a major obstacle in advancing the air pollution mitigation strategies in Kathmandu Valley because without collection of proper data, it is difficult to understand the relationship between emission of pollutant and their impact on air quality. The recent development on air quality monitoring is establishment of two air monitoring stations in the Kathmandu Valley; one is in Ratnapark and another in Pulchowk. However, these are not enough to monitor the real-time air quality of different places in the Kathmandu Valley. As urgent initiatives to control air pollution are required, two different control mechanisms can be implemented in the Kathmandu: long-term mechanisms and short-term mechanisms. Short-term mechanisms can be implemented immediately to halt the worse state of air pollution and long-term mechanisms can be implemented for full control of air pollution.

Short-term measures include the formulation of comprehensive action plans both at the national and local levels because without any proper strategy, nothing can be achieved. They can publish the Kathmandu Valley air pollution control guidelines to accelerate the air quality improvement in the Valley. The guidelines can outline the fugitive dust control, flue gas cleaning, and mobile source control measures focusing on key corporations, industries and regions such as tourist spots and areas along the high-traffic roads. As major pollution source in Kathmandu is vehicular emissions, and road construction, it can be prioritized in the control measures. Diesel-based and old vehicles can be reduced significantly. Low emissions zones can be declared in various important and polluted places in Kathmandu where private and high-emitting vehicles entry can be banned. The strong policies to vehicle ownership and usage controls can be implemented. For instance: congestion charges, increasing the vehicle and road taxes and insurances, high parking costs, restriction on private vehicles in certain areas. Implementation of such measures can begin with manual processes if the electronic systems are not supporting. Maintenance and construction of roads, water networks, and sewer networks can be safeguarded with the use of mobile applications to spots. Major dust prone areas of the roads and tourist areas can be vacuum cleaned. Such devices can be bought immediately. Unpaved roads can be paved. If it is not possible, such roads can be covered with gravel to control the dust particles. Old and high-emitting vehicles can be banned. The government can provide certain financial incentives for scrapping of very old vehicles and retrofitting (eg attaching tail-pipe treatment technologies) of not so old vehicles. Regular vehicle inspection policies can be adopted to assess road-emission performance, and penalties can be specified in case of violations.

In addition to traffic pollution controls, control measures can be enforced on other sectors as well. A complete ban with strict penalties can be implemented on solid wastes and burning of agricultural products. All the residents can start using cleaner fuels (eg liquefied petroleum gas (LPG)) and electricity instead of kerosene and diesel for cooking and lighting. The government can provide financial incentives to the low-income family to facilitate them to use such clean fuels. They can also use improved biomass stoves recommended by the World Health Organization for cooking. Brick manufacturing can either be banned inside the Valley or such industries can adopt air-purifying techniques such as vertical shaft kilns, Hoffman kilns, and tunnel kilns for brick manufacturing to reduce sulphates, nitrates, and black carbon emissions.  Besides these, one urgent measure can be a rotating one-weekday ban on use of private vehicles. Despite this, if pollution level does not decrease, the ban can be extended to two or more days in a week. Diesel electricity production can also be banned. 

Long-term measures for pollution control are comparatively difficult. It needs proper preliminary studies, robust planning, formulations and implementations of strict policy measures, and implementation of advanced technologies. At the moment, very few studies have pursued focusing on severe air pollution within Kathmandu. It is vital to perform long-term observations to understand the air pollution characteristics in Kathmandu. First, air pollution monitoring is very weak in Kathmandu as only two stations are available to measure air quality in this area. Such stations can be extended in several parts of the Valley and they can be equipped with modernized, automated, and digitalized informative systems. It is imperative that more detailed information on air quality is assessed on real-time system. In addition, it is important to recognize the most and least significant pollution sources to formulate air pollution control strategies. To do so, cities in Kathmandu Valley can also adopt transparent emission inventory systems. They can adopt various air pollution control measures for five-year, 10-year, or 20-year planning periods. The government and cities in the Valley can collaborate with successful cities to prevent or control air pollution. Academic observations and studies can be enhanced by collaborating with various institutions in the Kathmandu Valley.

To reduce significant pollution from traffic, construction of wider and paved roads with bicycle lanes can be prioritized. Infrastructure for electric vehicle routes and charging stations can be ensured. Tram routes and metro rail tracks can be constructed as soon as possible. Strategic policy measures can be implemented to increase distribution of electric and hybrid vehicles. This includes necessary financial measures and other promotional activities. Incomes collected at cities can be used for development of public transport so that shift toward larger use of public transportation will be realized. Awareness programs can be implemented to promote the use of bicycles. 

Strong business guidelines can be implemented to ensure availability of LPG for cooking to all levels of consumers. A pipeline network can be constructed to connect entire Valley homes to supply LPG. A long-term LPG financial incentives schemes can be offered to low-income families. Municipal solid waste can be managed scientifically, and precise strategies can be implemented to clean the Bagmati River, the Bishnumati River and other rivulets. Several wastewater treatment plants can be built to purify wastewaters. A robust strategic measure is required to collect, transport, and store agriculture residues and farm manures. Waste to energy production can be considered to manage solid wastes, agricultural residues, and farm manures. Largely polluting industries such as brick kilns can be phased out to ensure good air quality. Some manufacturing companies with higher emissions can be curtailed. Ozone can be controlled by controlling nitrogen oxides (NOx), volatile organic compounds (VOCs), and other GHG emissions.

If the government and the cities are keen to control air pollution in the Kathmandu Valley, these measures can be supportive for them.

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