Vegetative Noise Barrier: A Sustainable Solution for Urban Road Traffic Noise Reduction in Nepal

Abstract

In this report, we investigate if vegetative noise barriers can be used to treat urban road noise in Nepal. Noise pollution has grown to be a serious worry for Nepal as more and more people move to cities and the number of vehicles increases there. While they block noise well, typical noise barriers cost a lot to set up and maintain and don’t help the environment. The research assesses whether vegetative barriers, made up of trees, shrubs and greenery, help reduce traffi c noise by absorbing it, redirecting it and keeping people from hearing it. Field measurement of sound levels in chosen urban locations was combined with analyzing vegetation which clearly shows a decrease in ambient noise when barriers are in place. Besides, the research ensures that air is cleaner, the area is more eye-pleasing and wildlife is better protected which support the nation’s desire to be sustainable. Problems related to tiny spaces, routine plant care and the differences in climate are also examined. The results support adding vegetative noise barriers to city planning and noise strategies because they are less expensive to build, more sustainable and support healthier cities across Nepal.

Introduction

Urban growth in Nepal’s cities like Kathmandu, Pokhara, and Biratnagar has led to increased traffic noise pollution, which negatively impacts health and quality of life. Conventional noise barriers (concrete, metal) are effective but costly, inflexible, and environmentally unfriendly. Vegetative noise barriers—using trees, shrubs, and plants—are emerging as a sustainable alternative. They not only reduce noise but also improve air quality, store carbon, and enhance urban biodiversity.

Problem:
Despite rising noise concerns, Nepal has limited use or research on green noise barriers. Challenges include plant selection, limited urban space, and maintenance difficulties. More study is needed to optimize vegetative barriers for Nepal’s unique environment.

Objectives:

• Measure how much vegetative barriers reduce urban traffic noise.

• Review environmental and social benefits.

• Identify challenges in design and upkeep.

• Propose ways to integrate these barriers into Nepal’s urban planning.

Significance:
The study promotes eco-friendly noise management strategies suitable for Nepalese cities and encourages multidisciplinary collaboration and public awareness.

Scope and Limitations:
Focused on traffic noise in selected urban sites, the study assesses noise reduction and ecological/social impacts of vegetative barriers. Limitations include variability by plant species, seasonal changes, urban space constraints, and limited field data.

Literature Review:
Traffic noise harms health and wellbeing. Conventional barriers have drawbacks such as high cost, aesthetic issues, and noise reflection. Vegetation absorbs and diffuses sound without reflecting it, providing ecological benefits like pollution filtration and habitat creation. Evergreen dense shrubs perform best, and hybrid barriers (plants + conventional structures) enhance noise reduction. However, space and maintenance challenges exist, especially in fast-growing urban Nepal with difficult terrain and climate. Success depends on government, planners, environmentalists, and communities working together.

Methodology:
Noise levels were measured in selected sites in Kathmandu and Pokhara, comparing roadsides with and without vegetative barriers. Both quantitative (sound levels, plant characteristics) and qualitative (community and expert surveys) data were collected. The study also evaluated costs, environmental benefits, and urban planning implications.

Findings:
Vegetative noise barriers reduced average noise levels by about 7 dB compared to no barriers, effectively halving noise intensity. Taller barriers (3–4 meters) with dense plantings like Nepali Alder, Bamboo, Pine, Rhododendron, Sal Tree, and Ficus were most effective. Vegetative barriers also improve air quality and biodiversity, offering a multifunctional solution for Nepal’s urban noise problem.

Conclusion

In the end, this study suggests that using vegetative barriers is an effective and ongoing way to reduce the problem of road traffic noise in Nepal, helps to green the urban environment and improves how people live there. It is shown that noise attenuation is enhanced when the design parameters for barriers are optimized for a particular location. By including vegetative barriers in Nepal’s city designs, people enjoy cleaner air, more varieties of nature and a more attractive and stronger urban landscape. Although it is difficult due to small spaces, unpredictable weather and expensive upkeep, vertical greening and hybrid barriers offer possible answers to these problems. The benefits seen in this research equip policymakers, urban planners and environmental stakeholders to recommend more widely using vegetative noise barriers in noise reduction. More studies are needed that study urban composting in several regions through different seasons which will better demonstrate the lasting effect and positive environmental outcomes of this practice. Also, careful analysis of species options, long-term cost-benefit comparisons and introducing community-run maintenance models will earn these projects a future in Nepal. As we advance research and methods for noise reduction in cities, future projects will assist in preparing greener, quieter and sustainable urban spaces for this country and its growing number of city dwellers.

References

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Copyright

Copyright © 2025 Jay Prakash Yadav, Pankaj Yadav, Asst. Prof. Anil K. Choudhary. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.