Any undesirable changes on the quality of water that causes adverse effect on the health of human , animal as well as environment is water pollution. Water pollution remains a challenging issue for the sustainable development of Kathmandu Valley despite several infrastructural, awareness-raising and policy measures. Talking about water pollution , what comes in my mind first is Bagmati river . The Bagmati River runs through Nepal's Kathmandu valley, dividing the towns of Kathmandu and Patan, before passing through Madesh Province in southern Nepal and joining the Koshi River in Bihar, India. Both Hindus and Buddhists regard it as sacred. On its banks are a number of Hindu temples.

Kathmandu's prosperity has come at a cost to the Bagmati. Bagmati, Bishnumati, Dhobikhola, Manohara, Nakkhu, Balkhu, and Tukucha are seven tributaries, with five sub-tributaries: Godavari, Hanumante, Sangla, Mahadev, and Kodku Khola. The river is now more than a heavily industrialized, foul-smelling drain, and its ecosystem has been altered and altered beyond repair. Factory garbage, industrial waste, and household waste have all been poured into the river, treating it more like an open sewer than a sacred river. Experts say that, in addition to intense industrial activity, uncontrolled urbanisation, widespread sand mining, rising solid-waste dumping, a lack of public awareness, severe government neglect, and inadequate legislation are all contributing to the Valley's destruction.

 However, in the last decade or two, the government's efforts to reintroduce 'life' to the Bagmati have gained traction. It has the funds and a well-thought-out strategy. The issue remains, as with everything else in this nation, whether the administration can pull it off. The bigger, more significant question, which few seem to be addressing, is whether the Bagmati can be cleaned at all. The Soil Conservation Department launched the Bagmati Integrated Watershed Management Program (BIWM) and Technology Watershed in 1986 . The goal of this initiative is to improve the Bagmati Ecosystem's efficiency by involving communities and individuals in the ecosystem. Using participatory approaches for planning, implementation, and monitoring, BIWMP has been able to form a partnership between community institutions, agencies, and district authorities. Friends of the Bagmati (FOB) is a group of people from varied backgrounds who have banded together to restore the Bagmati's and other Nepalese rivers' environments. The friends' goal is to restore the Bagmati and other valley streams by bringing local consciousness to light in various ways and stressing the Bagmati's sanctity. The FOB has pledged to safeguard the Bagmati River from pollution and other threats, as well as its significant economic, cultural, and heritage importance.

Reference

https://earth5r.org/saving-river-bagmati/

https://chinadialogue.net/en/cities/4321-the-dead-rivers-of-kathmandu/