Environmental Challenges and Sustainable Solutions for New Delhi’s Urban Future

Dr. Anil Kumar Yadav Assistant Professor (Department of Geography) Alankar P.G. Mahavidyalaya Jaipur

Abstract

New Delhi, India, a city recognized for its rapid economic development and growing global influence, faces severe environmental challenges that threaten its sustainability and public health. This paper explores the major ecological issues plaguing the region, primarily caused by explosive population growth, unregulated industrial expansion, and the extensive use of fossil-fuel-powered transportation. These pressures have led to critical levels of air pollution, significant contamination of the Yamuna River, and widespread deforestation in the Aravalli Hills. The study employs a qualitative methodology, drawing from secondary data sources, to assess the causes and consequences of these issues. It also evaluates the effectiveness of existing government interventions and suggests comprehensive solutions such as strategic urban planning, promotion of clean energy, improved sewage and transportation infrastructure, and stronger conservation policies. The paper emphasizes that immediate, sustainable action is essential to mitigate further environmental degradation and to safeguard the health and livability of New Delhi for future generations.

Keywords: Deforestation, urbanization, population growth, sustainable development,environmental policy, clean energy, transportation infrastructure.

Introduction

New Delhi, India, while often recognized for its dynamic economic expansion and appeal to foreign investors, continues to grapple with numerous environmental challenges. This paper opens with a brief overview of the city, highlighting its current economic progress, growing population, and investment potential. This context sets the stage for understanding the root causes of the region’s environmental problems. Key contributors such as rapid population growth, intense industrialization, and

increased transportation usage are examined in detail. The paper also reviews the measures currently being taken by government bodies to address these challenges. It concludes by presenting a range of possible strategies that New Delhi’s government could adopt to enhance the city’s overall livability.

The growing population and rapid urban development in New Delhi have led to serious environmental issues, including reliance on unclean energy sources and increased transportation usage—both major contributors to the city’s severe air pollution and persistent smog. Furthermore, the city’s high demand for resources, combined with the government’s responsibility to provide adequate housing and meet both basic and luxury needs of its residents, presents a significant challenge. These pressures have resulted in severe water pollution in the Yamuna River, widespread deforestation—especially in the Aravalli hill region—loss of biodiversity and natural resources, and the gradual disappearance of rural land surrounding the city (Raut&Raut, 2013). Addressing these environmental concerns is critical for safeguarding public health and ecological stability. Achieving this will require strategic urban planning and the adoption of sustainable development practices.

Study Area

Located in northern-central India, New Delhi is a thriving and densely populated city that has served as the capital of India since February 1911 (Wright, 2011). It houses the central seats of India’s executive, legislative, and judicial branches, with Lieutenant Governor Najeeb Jung currently in office (New Delhi, 2014). Beyond its political significance, New Delhi’s economy is rapidly advancing, positioning the city as one of the most economically progressive areas in the country. Notably, in 2012, it drew comparisons to Beijing’s economic rise when thirteen major international franchises entered its market (Vats, 2013). That same year, the city recorded a 9% economic growth rate, with projections estimating a rise to 11.5% by the end of 2017 (India Brand Equity Foundation, 2014). This economic success is largely due to New Delhi’s strategic central location and close proximity to key government institutions. In addition to a strong retail sector, its status as the national capital makes it a hub for international trade, business, corporate services, real estate, and financial institutions (India Brand Equity Foundation, 2014).

New Delhi is widely regarded as an attractive destination for industrial and corporate investment. One key indicator of its economic strength is its Gross Domestic Product (GDP), which positioned the city as the second-highest among Indian cities, with a GDP of $167 billion in 2012 (Top 15 Indian Cities, 2012). Another major factor driving the city’s growth is its strong consumer demand. With a population of 25 million in 2014, New Delhi ranked as the second most populous city in the world, just behind Tokyo (United Nations Department of Economics and Social Affairs, 2014). This rapidly growing population continues to fuel a rising demand for goods and services, further contributing to the city’s economic expansion.

New Delhi, in northern India, borders the states of Uttar Pradesh and Haryana and spans 1,483 square kilometers with a width of about 48.5 km (Delhi Department of Planning, 2006). Two key geographical features are the Yamuna River and the Aravalli Hills. The Yamuna, originating in the Himalayas, is northern India’s largest tributary of the Ganges and flows 1,370 km through Uttar Pradesh and Haryana (Kansal& Sharma, 2011). Its drainage basin covers about 11% of India’s land area (Gopal&Sah, 1993) and supports dense populations, agriculture, and industry. Historically vital as New Delhi’s main water source, the river still holds religious importance and currently supplies 724 million of the 1,150.2 million cubic meters of water the city uses annually (Kansal& Sharma, 2011).

The second prominent feature, is the Aravalli Hills Range located in north- west India within the Haryana State, passing through New Delhi as well.  The mountain range stretches for a total of 692  km and   is one of the oldest  hill terrains in the world  (Rathore,  2009).   The region itself contains   a multitude of forests, natural resources, and minerals.  It acts as a climate and precipitation control, and an   air   filtration  system  for  the  surrounding  Indian  states.    These   attributes   of   the  hill  range  are extremely important, as  they  not only act in the benefit  of   the health of citizens living within  New  Delhi, but also control rainfall and climate, which keeps agriculture production and desert regions in check.     In  addition  to  these  environmental  advantages,   Aravalli  also  offers  a  variety  of  valuable minerals  that  have since  been  a  valuable source   for the   mining industry.   Some  of  these  mineral  offerings include silver, gold, marble, zinc, emerald, garnet, and many others  (Rathore, 2009).  It is evident  that the  preservation  of both  of  New  Delhi’s  geographic   land  forms  will   allow  for  many environmental, economic, and health- related benefits of the city.

The Aravalli Hills, one of the world’s oldest mountain ranges, extend 692 km through north-western India, including Haryana and parts of New Delhi (Rathore, 2009). The range plays a critical role in regulating climate, rainfall, and air quality, supporting agriculture and limiting desertification. It also contains forests and significant mineral resources such as silver, gold, marble, zinc, and emeralds, contributing to regional mining activity. Preserving the Aravallis is essential for maintaining New Delhi’s environmental stability, public health, and economic sustainability.

The case study concludes that to support New Delhi’s rapidly growing population, it is essential to sustainably preserve the city’s natural resources. New Delhi faces escalating environmental challenges, including degradation due to overpopulation, water pollution—particularly in the Yamuna River—deforestation in the Aravalli Hills, and severe air pollution and smog. These issues will be examined in detail in the Environmental Issues section of this paper.

Objectives

• To highlight the importance of sustainable preservation of New Delhi’s natural resources amid rapid population growth.
• To identify and discuss key environmental challenges faced by New Delhi, including overpopulation and resource degradation.
• To analyze water pollution issues, focusing on the contamination of the Yamuna River.
• To examine the effects of deforestation in the Aravalli Hills and its environmental impact.
• To assess the severity and causes of air pollution and smog within the city.
• To provide a foundation for exploring potential solutions to New Delhi’s environmental problems

Research Methodology

This study employs a qualitative research approach to analyze the environmental challenges faced by New Delhi amid its rapid economic and population growth. Data collection involves a comprehensive review of existing literature, including academic journals, government reports, case studies, and reputable online sources related to New Delhi’s geography, economy, and environmental issues.

Secondary data sources such as government publications and statistical databases provide up-to-date information on demographic trends, economic growth rates, and pollution levels. Secondary sources, including research papers and environmental assessments, offer insights into the causes and impacts of issues like water pollution, deforestation, and air quality degradation.

The research synthesizes these findings to identify key environmental stressors, assess their implications for the city’s health and sustainability, and evaluate the effectiveness of current government policies. The study also explores potential sustainable solutions based on best practices highlighted in the literature.

By integrating multidisciplinary perspectives from urban planning, environmental science, and economics, the methodology ensures a holistic understanding of the complex factors influencing New Delhi’s environmental situation.

Result and Discussion

Cause of Environmental issues

The primary factors driving New Delhi’s environmental problems are rapid population growth, expanding industrial development, and extensive transportation use (Government of NCT of Delhi Department of Planning, 2014).

1. Population Growth

New Delhi has experienced rapid population growth, especially over the past decade, making it one of the fastest-growing urban areas globally. The population surged from around 1.5 million in 1951 to 22.6 million in 2011 (Cox, 2011). If this trend continues, the population is projected to reach 23 million by 2021 (Raut&Raut, 2013), and by 2030, it may surpass the population of Australia (Stancati, 2012). Such explosive growth significantly intensifies existing environmental challenges and pressures on the city’s resources.

Rapid rural-to-urban migration is increasing pressure on both New Delhi’s environment and government to manage the city’s growth. Between 1961 and 2001, the urban area expanded from 22% to 62.5%, while population density rose sharply from 1,176 to 9,294 people per km² (Kumar, 2009). Additionally, rising demand for business and services has made rural living less attractive, reflected by a decline in rural villages from 214 in 1981 to 112 in 2011 (Delhi Department of Planning, 2006).

2. Industrial Development

New Delhi’s population growth is largely driven by its economic, social, and industrial appeal. The city has seen significant industrial development and aims to expand this sector further through the Industrial Policy for Delhi 2010-21. This policy introduces measures like the Business Facilitation Council to streamline approvals, simplify registrations, and support industrial services (India Brand Equity Foundation, 2014). However, despite intentions to promote cleaner industries, increased industrial influx risks worsening urban sprawl and overpopulation. Currently, only 20% of industries operate in designated areas, with many located in residential and commercial zones due to poor planning (Government of NCT of Delhi Department of Planning, 2014). This mismanagement contributes to environmental degradation, exemplified by pollution in the Yamuna River (Singh, 2014).

3. Transportation

Transportation is a major contributor to New Delhi’s environmental issues, especially air pollution. Despite buses being available to 60% of commuters in 2003, only 1% used them, while about 94% relied on personal or motorized vehicles (Das et al., 2010). These vehicles emit large amounts of carbon monoxide, nitrogen oxides, and hydrocarbons, worsening air quality and smog (Doberstein, 2012). High traffic also leads to congestion and increased accidents, with three out of ten accidents resulting in fatalities, and 75% of those involving pedestrians, cyclists, or two-wheelers (Rakesh, 2013; Tiwari, 2003). This paper will further explore strategies to improve transportation infrastructure to reduce pollution and enhance safety.

Environmental Issues

• Air Pollution

Air pollution is defined as “the introduction of chemicals, biological matter, or particulates into the atmosphere” (Doberstein, 2012, p. 264). For a mega-city like New Delhi, this is a major environmental concern.

According to a 2007 study conducted by the Central Pollution Control Board, Delhi had the highest emission levels of pollution among all Indian cities (Sequeira, 2008). Furthermore, a study conducted in November 2010 by the University of Delhi revealed alarming pollution levels. The concentration of particulate matter in the air was recorded at 908 micrograms per cubic meter—more than nine times the healthy standard of 100 micrograms per cubic meter (Mandhana, 2012). This clearly indicates that air quality in the capital is significantly worse than acceptable health standards.

One major contributor to this problem is the increase in the city’s population, which has led to a sharp rise in the number of vehicles on the roads. Between 1997 and 2006, the number of vehicles in New Delhi increased by three million (Sequeira, 2008). Additionally, around 1,400 new vehicles are added to the city’s roads every day. This surge in vehicular traffic has contributed to an approximate 50% increase in particulate matter over the past ten years (Mandhana, 2012).

Industrial emissions are another significant source of pollution. Coal-powered factories, in particular, contribute substantially to the city’s declining air quality. According to an article from Deutsche WelleAkademie, these factories are responsible for an astonishing 80% of New Delhi’s total air pollution (DW, 2014). The same article ranked New Delhi as the fourth worst city in the world for smog.

• Health Impacts of Air Pollution in New Delhi

In addition to its environmental consequences, air pollution in New Delhi is also a major contributor to serious public health concerns. Research has established a strong correlation between air pollution and both cardiac and respiratory ailments (Ministry of Environment and Forests India, 2008). This connection is evident in several case studies.

For example, a 2008 study conducted by the Central Pollution Control Board compared a rural region, such as West Bengal, with an urban area like New Delhi. The findings showed that respiratory conditions were nearly twice as common in New Delhi (Gupta et al., 2013). The same scholarly article also highlighted another study, which revealed that increases in deaths due to natural causes strongly correlated with rising pollution levels in the city.

These findings emphasize the urgent need for New Delhi to take immediate and effective action to combat air pollution and protect public health.

• Efforts to Combat Air Pollution in New Delhi

Although the city has made efforts to reduce carbon emissions and improve air quality, current trends in transportation and population growth continue to outweigh these initiatives. Since 2000, New Delhi has mandated that all motorized vehicles must use compressed natural gas (CNG), and older vehicles are no longer permitted on the roads. Additionally, the introduction of a metro system and an expanded fleet of public buses were steps taken to reduce reliance on private vehicles. The city is also in the process of developing further strategies and policies to address the growing crisis (Mazoomdar, 2014).

While these initial efforts are commendable, substantial progress has yet to be seen. If New Delhi fails to adequately confront the challenges of rapid population growth, reliance on unclean energy sources, expanding industrial activity, and heavy transportation usage, air pollution will remain a persistent and severe burden for the city—and the nation—in the years to come

• Water Pollution and the Yamuna River in New Delhi

Water is a fundamental source of life. Communities with access to a clean and reliable water supply benefit in numerous ways, including improved household access, enhanced agricultural production, and industrial development. Moreover, water supports human health, plant growth, animal life, and overall biodiversity (Kumar et al., 2005).

The Yamuna River, once a major source of water for the city of New Delhi, is now severely polluted and no longer fit for consumption. The most contaminated section of the river—approximately 22 kilometers—flows directly through New Delhi. The pollution originates from both industrial and domestic sources, with an estimated 85% of it coming from untreated household waste (Kansal& Sharma, 2011). Additional pollutants include pesticides, toxic waste from factories and power plants, and untreated sewage (Ramachandran, 2012).

The river’s ability to naturally cleanse itself has been significantly compromised. Due to overexploitation and reduced water flow, the Yamuna can no longer sustain the natural filtration processes needed to maintain water quality. As a result, the once-thriving fishing industry in the region has collapsed (Gopal&Sah, 1993).

Moreover, the impact of pollution is not limited to the Yamuna River itself. The contamination has also spread to New Delhi’s underground aquifers—another major water source for the city. According to the National Institute in New Delhi, groundwater in the region has become polluted with toxic substances, rendering it unfit for use (Ramachandran, 2012).

In response to the crisis, the government launched two major initiatives to revive the river. The Yamuna Action Plan (YAP) Part One, introduced in 1993, focused on improving sewage infrastructure by building pumping stations and sewage treatment plants. However, despite being a multi-billion-dollar effort, the World Wide Fund for Nature (WWF) reported minimal progress, largely due to poor planning and an underestimation of the volume of sewage the city would produce. Additionally, only 55–75% of the infrastructure built was being used to its full potential.

A second phase, Yamuna Action Plan Part Two, was launched in 2004 with similar goals. Unfortunately, the results were much the same. According to a lecture at the Yamuna River Conference, “After YAP 1 and YAP 2, the standards of the river have not been met in Delhi” (Kansal& Sharma, 2010).

• Deforestation in the Aravalli Hills Range

Deforestation is the process by which forests or vegetation are lost due to various circumstances (Doberstein, 2012, p. 257). The Aravalli Hills Range, located near New Delhi, has experienced significant deforestation as population growth and urban development continue to accelerate. A research study by ACRS (2002) reported that within a 20-year period in the early 20th century, natural vegetation in the region decreased dramatically—from 80% to just 40% (Rathore&Sukhadia, 2002). The same study estimated that the area is losing approximately 1.5 square kilometers of forest each year. If this rate of loss continues, forest coverage is projected to fall to around 15% within the next fifteen years.

Key contributors to this decline include various land development activities such as irrigation projects, road construction, agriculture, and residential expansion, all driven by increasing population pressure (Rathore&Sukhadia, 2002). Additionally, the overexploitation of natural resources—such as timber, fuelwood, and minerals through mining—is accelerating the pace of deforestation.

This deforestation poses a serious disadvantage for New Delhi. Forests serve as vital components of urban ecosystems. They function as natural air filtration systems—an essential service in a city struggling with dangerously high levels of air pollution. Furthermore, forests help regulate climate and rainfall, prevent soil erosion, serve as habitats for diverse species, and promote ecological balance and biodiversity (Doberstein, 2012, p. 257).

Despite these critical benefits, conservation efforts in the Aravalli Hills Range have been insufficient. According to The Hindu, large parts of the Aravalli forests are not protected under the Forest Conservation Act of 1980. Moreover, the government recognizes only limited portions of the range as forests under the outdated Punjab Land Preservation Act of 1900, highlighting the lack of serious legal and environmental commitment to preserving these vital green spaces (Dogra, 2013).

Solutions

The following sections propose a series of actionable solutions that the New Delhi government should strongly consider to address its most pressing environmental challenges: air pollution, degraded water quality in the Yamuna River, and deforestation in the Aravalli Hills Range. These strategies aim to tackle the root causes of these issues—such as overpopulation and unregulated urban growth—by improving transportation systems, enhancing sewage infrastructure, and preserving biodiversity through smarter city planning and resource management.

• Controlled Planning in Suburban Development

New Delhi is currently expanding at an unsustainable rate, with much of its development occurring without adequate control or urban planning. This has resulted in significant urban sprawl, as the city stretches into surrounding peripheral areas to accommodate its growing population. One effective planning model that New Delhi could emulate is the East Clayton Neighborhood Development in Surrey, British Columbia, Canada. This project was specifically designed to house a rapidly growing population while maintaining sustainable development practices.

The East Clayton model involved community participation in the planning process and prioritized the integration of sustainable features. For example, it minimized pavement coverage to reduce environmental disruption and used land more efficiently by building higher-density housing (Bunting et al., 2010, p. 256). Applying a similar approach in New Delhi—by constructing high-rise residential complexes close to the city center—would allow more people to live in a smaller footprint, significantly reducing the need for long commutes and decreasing dependence on private transportation.

According to the Population Reference Bureau, many individuals who work in New Delhi commute from surrounding areas, contributing to traffic congestion and emissions (Haub& Sharma, 2007). Creating livable, high-density urban centers would allow more people to live where they work, reducing the strain on infrastructure and helping to protect ecologically sensitive areas like the Aravalli Hills from further development and deforestation.

• Decentralization

Another strategy that could alleviate New Delhi’s environmental and infrastructural pressures is decentralization. As suggested by The Wall Street Journal, decentralizing the city’s functions can reduce traffic congestion and idle time on roads, which in turn lowers air pollution (Stancati, 2012).

Decentralization involves designating specific parts of the city as specialized zones for various functions—such as business, administration, healthcare, retail, and education—based on their existing infrastructure and demographic makeup. This specialization could distribute the city’s daily traffic load more evenly and reduce the necessity for long-distance travel across the city.

Moreover, promoting remote work by encouraging businesses to provide their employees with the tools and technologies needed to work from home can further reduce the number of vehicles on the roads. As seen during global lockdown periods, remote work has a measurable impact on reducing traffic and emissions—making it a practical and immediate part of a broader long-term environmental strategy.

·         Clean Energy

The New Delhi government must establish clear and measurable goals for reducing carbon emissions and actively work toward achieving them within a specified time frame. A key step is to invest in and promote the use of renewable energy sources such as solar and wind power. These alternatives could be used to power public infrastructure like streetlights, government buildings, and industrial operations (Do Something Organization, n.d.).

In addition, existing buildings should be retrofitted to increase energy efficiency. A useful model is the Better Buildings Partnership in Toronto, which focuses on improving energy systems within buildings through upgrades such as improved lighting, efficient heating and cooling systems, and the integration of renewable energy (Bunting et al., 2010, p. 255).

To further combat pollution and enhance urban aesthetics, the city should also mandate that all high-rise buildings incorporate green roofs or rooftop gardens. These not only help filter air naturally but also provide insulation and increase biodiversity (Do Something Organization, n.d.).

·         Improving Transportation Infrastructure

Transportation is a significant contributor to New Delhi’s air pollution. Reducing automobile use and encouraging public and active transportation are critical steps in lowering CO₂ emissions.

This can be accomplished through three main actions:

• Increasing taxes on automobiles, especially diesel-powered vehicles.
• Raising parking costs to discourage car use.
• Improving the accessibility, reliability, and coverage of public transit systems (Mandhana, 2012).

According to the World Health Organization, additional transportation infrastructure improvements include:

• Constructing elevated roads and synchronizing traffic lights to ease congestion.
• Extending metro rail systems into suburban areas.
• Increasing the fleet of efficient public buses (Tiwari, 2003).

One innovative solution is the introduction of electric hybrid buses. Volvo, for example, is developing buses that reduce fuel consumption and emissions by 80% (Volvo, n.d.). Furthermore, active transportation—such as cycling and walking—should be supported by developing safe and spacious routes. The City of Thunder Bay’s transportation strategy serves as a strong model, with designated bike and pedestrian lanes integrated into public transit routes, alongside signage and safety regulations (City of Thunder Bay, 2008).

·         Maintaining the City’s Geographic Landscapes

Preserving New Delhi’s natural landscapes, particularly the Yamuna River and the Aravalli Hills Range, is essential for the city’s long-term sustainability.

To protect the Yamuna River, the city must:

• Promote water-saving practices like the use of efficient toilets.
• Modernize sewer systems to handle large volumes of wastewater.
• Establish decentralized wastewater treatment plants to prevent untreated sewage from entering the river (Misra, 2010).

To conserve the Aravalli Hills Range, stricter land-use policies must be enacted. Development projects should be limited in ecologically sensitive zones. Additionally, residents should be encouraged to increase local biodiversity by planting trees and participating in conservation efforts (Rathore&Sukhadia, 2002).

Conclusion

This paper has outlined the environmental consequences of New Delhi’s rapid growth, including unchecked population expansion, industrialization, reliance on fossil fuels, and increased vehicle usage. These factors have led to some of the highest air pollution levels in India—nearly ten times higher than the recommended health standards.

Key solutions include:

• Urban planning strategies that encourage high-density development close to the city to reduce sprawl.
• Improvements in public transit, active transportation infrastructure, and the introduction of hybrid buses to lower carbon emissions.
• Decentralization of urban functions to ease congestion.
• Investment in renewable energy (solar, wind) and the adoption of green building practices to reduce fossil fuel dependency.
• Wastewater infrastructure upgrades to prevent further pollution of the Yamuna River.
• Strict conservation policies to protect the forests of the Aravalli Hills and maintain the city’s biodiversity.

If New Delhi fails to take decisive action, the environmental degradation will only worsen—posing serious threats to public health, ecological stability, and the city’s long-term sustainability. However, with coordinated planning, responsible governance, and community involvement, it is still possible to reverse the environmental decline and build a cleaner, healthier, and more sustainable future.

References

1. Bunting, T., Filion, P., & Walker, R. (2010).Canadian cities in transition: New directions in the twenty-first century (4th ed.). Oxford University Press.
2. City of Thunder Bay.(2008). Active transportation plan.Thunder Bay City Planning Department. Retrieved from https://www.thunderbay.ca
3. Cox, W. (2011).Urban population and density trends in India.Demographia. Retrieved from https://www.demographia.com
4. Das, A., Parida, M., & Jena, C. (2010).Assessment of public transportation in Delhi.Journal of Public Transportation, 13(1), 121–134. https://doi.org/10.5038/2375-0901.13.1.6
5. Delhi Department of Planning.(2006). Statistical handbook of Delhi 2006.Government of NCT of Delhi.
6. Do Something Organization. (n.d.).Green roofs and energy. Retrieved from https://www.dosomething.org
7. Doberstein, B. (2012). Environmental issues. In B. Mitchell (Ed.), Resource and environmental management in Canada: Addressing conflict and uncertainty (4th ed., pp. 257–264). Oxford University Press.
8. Doberstein, B. (2012). Environmental issues. In B. Mitchell (Ed.), Resource and environmental management in Canada: Addressing conflict and uncertainty (4th ed., pp. 257–264). Oxford University Press.
9. Dogra, B. (2013, March 17). Aravallis not protected by Forest Conservation Act. The Hindu. Retrieved from https://www.thehindu.com
10. DW Akademie. (2014). Delhi’s deadly smog: Causes and consequences. Deutsche Welle. Retrieved from https://www.dw.com
11. Gopal, B., &Sah, M. (1993). Conservation and management of rivers in India: Case-study of the River Yamuna. Environmental Conservation, 20(3), 243–254. https://doi.org/10.1017/S0376892900038215
12. Gopal, B., &Sah, M. (1993). Conservation and management of rivers in India: Case-study of the River Yamuna. Environmental Conservation, 20(3), 243–254. https://doi.org/10.1017/S0376892900038215
13. Government of NCT of Delhi Department of Planning.(2014). Economic survey of Delhi 2013–14. Retrieved from https://delhiplanning.nic.in
14. Gupta, P., Christopher, S. A., Wang, J., Gehrig, R., Lee, Y. C., & Kumar, N. (2013).Satellite remote sensing of particulate matter and air quality assessment over global cities.Atmospheric Environment, 40(30), 5880–5892. https://doi.org/10.1016/j.atmosenv.2006.03.016
15. Haub, C., & Sharma, O. P. (2007).India’s population realities.Population Reference Bureau. Retrieved from https://www.prb.org
16. India Brand Equity Foundation. (2014). Delhi: The capital of India. Retrieved from https://www.ibef.org/states/delhi.aspx
17. Kansal, A., & Sharma, H. (2010).Environmental challenges and restoration of Yamuna River in Delhi.Proceedings of the Yamuna River Conference, Delhi University.
18. Kansal, A., & Sharma, H. (2011).Water quality assessment of river Yamuna.Journal of Environmental Management, 91(6), 134–142.
19. Kansal, A., & Sharma, H. (2011).Water quality assessment of river Yamuna.Journal of Environmental Management, 91(6), 134–142.
20. Kumar, A., Sharma, M. P., & Sharma, D. (2005). Water resource management in urban India: A case study of Delhi. Indian Journal of Environmental Protection, 25(8), 680–688.
21. Kumar, R. (2009). Urbanization and environmental problems in India.Sarup Book Publishers.
22. Mandhana, N. (2012, November 6). Air pollution kills in India too. The Wall Street Journal. Retrieved from https://www.wsj.com
23. Mazoomdar, R. (2014). Delhi’s clean air illusion.India Today. Retrieved from https://www.indiatoday.in
24. Ministry of Environment and Forests India.(2008). National action plan on climate change.Government of India. Retrieved from https://moef.gov.in
25. Misra, A. K. (2010). A river about to die: Yamuna. Journal of Water Resource and Protection, 2(5), 489–500. https://doi.org/10.4236/jwarp.2010.25056
26. New Delhi. (2014). In Encyclopædia Britannica. Retrieved from https://www.britannica.com/place/New-Delhi
27. Rakesh, S. (2013, February 18). Road safety in Delhi: A major concern. The Times of India. Retrieved from https://timesofindia.indiatimes.com
28. Ramachandran, R. (2012). Urban water supply and pollution in India: The case of the Yamuna River. Indian Institute for Human Settlements.
29. Rathore, C. S. (2009). Forest cover change in the Aravalli hills range: A remote sensing and GIS approach. International Journal of Remote Sensing and GIS, 1(2), 54–63.
30. Rathore, C. S., &Sukhadia, R. (2002). Forest cover mapping and change detection in Aravalli hills of Rajasthan using remote sensing and GIS. Asian Conference on Remote Sensing (ACRS).
31. Raut, N., &Raut, N. (2013). Environmental issues in India and sustainable development: A geographical analysis. International Journal of Social Science Tomorrow, 2(2), 1–6.
32. Sequeira, S. (2008).Pollution crisis in Delhi.The Times of India. Retrieved from https://timesofindia.indiatimes.com
33. Singh, R. (2014). Impact of industrialization on water quality of Yamuna River: A case study. International Journal of Advanced Research, 2(10), 543–550.
34. Stancati, M. (2012, October 10). India looks for ways to cut traffic and pollution. The Wall Street Journal. Retrieved from https://www.wsj.com
35. Stancati, M. (2012, October 10). India looks for ways to cut traffic and pollution. The Wall Street Journal. Retrieved from https://www.wsj.com
36. Tiwari, G. (2003). Transport and land-use policies in Delhi.Bulletin of the World Health Organization, 81(6), 444–450.
37. Tiwari, G. (2003). Transport and land-use policies in Delhi.Bulletin of the World Health Organization, 81(6), 444–450.
38. Top 15 Indian cities by GDP.(2012). India Times. Retrieved from https://economictimes.indiatimes.com
39. United Nations Department of Economic and Social Affairs. (2014). World urbanization prospects: The 2014 revision. Retrieved from https://population.un.org/wup
40. Vats, M. (2013). Global brands flock to Delhi. The Economic Times. Retrieved from https://economictimes.indiatimes.com
41. Volvo.(n.d.).Hybrid electric buses: The future of city travel. Volvo Group. Retrieved from https://www.volvogroup.com
42. Wright, T. (2011).A history of India (2nd ed.). Routledge.