Groundwater Quality in the Kathmandu Valley: Contaminants, Human Health Risks and the Path Forward

Dorkaji Shrestha; Bhesh Kumar Karki; Bijay Thapa; Shukra Raj Paudel

doi:10.63095/NBSEH.25.198609

Authors

Dorkaji Shrestha Environmental Engineering Program, Department of Civil Engineering, Pulchowk Campus, Institute of Engineering, Tribhuvan University (ROR: https://ror.org/02rg1r889), Lalitpur, Nepal
Bhesh Kumar Karki Department of Civil Engineering, Thapathali Campus, Institute of Engineering, Tribhuvan University (ROR: https://ror.org/02rg1r889), Kathmandu, Bagmati Province, Nepal
Bijay Thapa Department of Environmental Science and Engineering, Kathmandu University (ROR: https://ror.org/036xnae80), Dhulikhel, Nepal
Shukra Raj Paudel Environmental Engineering Program, Department of Civil Engineering, Pulchowk Campus, Institute of Engineering, Tribhuvan University (ROR: https://ror.org/02rg1r889), Lalitpur, Nepal

DOI:

https://doi.org/10.63095/NBSEH.25.198609

Keywords:

Groundwater quality, Contaminants, Human health risk, Kathmandu Valley

Abstract

Anthropogenic and geogenic activities have intensified pressure on groundwater resources and increased contamination. Rapid urbanization in the Kathmandu Valley has led to a decline in groundwater quality, raising public health risks at an alarming rate. Previous studies show a growing load of contaminants, highlighting the need for sustainable and safe groundwater management strategies. Therefore, this analysis demonstrates contamination levels in Kathmandu Valley groundwater, evaluates associated health problems, and identifies future research and policy priorities to ensure groundwater security. A comprehensive meta-analysis of peer-reviewed literature (2002–2024) was conducted, followed by a quantitative health risk assessment evaluating carcinogenic and non-carcinogenic risks. The findings indicate that females face higher risks to both carcinogenic and non-carcinogenic effects. Children are the most vulnerable group because of their physiological sensitivity and exposure duration. Future reforms should include integrated water resource management, stronger legal frameworks, and community-based solutions to safeguard aquifers from contamination and protect both human health and the environment. Additionally, interdisciplinary collaboration among hydrologists, epidemiologists, and policymakers is essential to reduce long-term health and ecological impacts.

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