A geospatial analysis for an integrated land use and water strategy

Are cultural activities connected to river pollution? This is a question that often flies under the radar. Dr Pamela Duran Diaz, IHS Senior Planning Specialist, answered this question in a recent chapter titled "A Geospatial Analysis for an Integrated Land Use and Water Strategy for Bagmati River in Kathmandu, Nepal". In this interview, Pamela sheds light on the role of individual actions and contributions in driving positive change toward environmental sustainability.

Why the Bagmati River

Many years ago, Pamela traveled through India, where she was deeply moved by the cremations at the shores of the Ganges River in Varanasi. "I started pondering the impact that these cultural practices would have on water quality." A student from Nepal explained to her that the Bagmati River is considered holy by both Hindus and Buddhists. Additionally, the Pashupatinath Temple, where the main cremation Ghats are located in Kathmandu, was severely damaged by earthquakes and thus threatened to be removed from UNESCO World Heritage list.

"This sparked a quest within me to find ways to preserve both the cultural practices and the riparian ecosystems of the Bagmati River."

Low-quality water sources

The studies revealed that the Bagmati river is nearly oligotrophic from its source due to irregular settlements. Subsequently, agricultural runoffs containing nitrates, ammoniums, phosphorus, and heavy metals from pesticides and fertilizers exacerbate the issue. By the time the water reaches the urban core, it supports no life at all, but the challenges do not end there. All households discharge their wastewater into the river, effectively turning it into an open sewer. Despite the efforts to clean it, the conditions remain challenging, significantly impacting the health of residents in the Kathmandu Valley. "However, through water sampling at 10 different locations and contrasting it with geospatial information on different land uses, we managed to demonstrate that the primary organic matter polluting the river is not ashes from the cremations, but rather faecal E. Colis, attributed to inadequate wastewater management and infrastructure."

"Access to clean water and improved sanitation not only enhances public health but also preserves cultural heritage and identity."

Next steps

The role of the local government in the formulation, monitoring, and enforcing water management policies is crucial. Urgent action is needed to build a network of sewage lines that would divert wastewater from the river, along with activating existing water treatment plants (that were not operative at the time of data collection). This must be accompanied by advocacy campaigns to raise awareness among the local population to prevent further pollution of the Bagmati river.

"These initiatives are imperative to restore the riparian ecosystems, mitigate health threats to the population, and preserve the local cultural practices around the river, including cremations."

Research implications

Through their research, the team delved into the intricate relationship between urban development and environmental well-being along the Bagmati River. "By identifying pollution sources and advocating for specific solutions like sewage infrastructure and wastewater treatment, our findings offer actionable insights, tailored for policy-makers and urban planners." For the local communities residing by the river, the impact is profound. Access to clean water and improved sanitation not only enhances public health but also preserves cultural heritage and identity.

"Ultimately, our research promotes a vision of sustainable urban development, empowering communities to safeguard their natural and cultural heritage for generations to come."

More about the author

Dr. Pamela Duran Diaz is a Senior Planning Specialist and lecturer in the master’s track on Strategic Urban Planning and Policies at IHS. Concurrently, she is pursuing a Habilitation in Sustainable Land Governance for WEF Systems at the Technical University of Munich.

Read the full bio