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Bagmati River Restoration Initiative

बागमती नदी पुनर्स्थापना पहल

A Water-Energy-Food Nexus Approach to Revitalizing Nepal's Sacred River

Executive Summary

The Bagmati River, sacred to millions in Nepal's Kathmandu Valley, is in a state of ecological crisis due to severe pollution from untreated sewage, industrial effluent, and solid waste. This degradation poses significant risks to public health, destroys aquatic ecosystems, and prevents the use of river water for agriculture, threatening the food security and livelihoods of the valley's burgeoning population.

The Bagmati River Restoration Initiative proposes an innovative, scalable, and sustainable solution leveraging AquaSai's proven Multi-Stage Recirculating Constructed Wetland (MSR) technology. This project directly addresses the Water-Energy-Food nexus by:

Water

Deploying a nature-based system to treat polluted river water, significantly improving water quality and enabling its safe reuse.

Food

Providing a reliable source of treated, nutrient-rich water for urban and peri-urban agriculture, enhancing food security, and creating economic opportunities.

Energy

Harvesting biomass from the wetland's specially selected plants to generate biogas, providing a renewable energy source for local communities.

Our approach is unique in its integration of phytoremediation plants native to Nepal, including species with high value in Ayurvedic and traditional medicine, creating a circular economy. This initiative is designed as a scalable social enterprise, with a strong focus on empowering women and vulnerable communities through training, employment, and new livelihood creation.

The Problem: A Sacred River in Peril

The Bagmati River is the lifeline of the Kathmandu Valley, yet it has become a de facto sewer. Decades of rapid, unplanned urbanization have overwhelmed the valley's sanitation infrastructure. Our research, supported by numerous scientific studies, confirms the critical state of the river:

Extreme Organic Pollution

Biochemical Oxygen Demand (BOD) levels frequently exceed 120 mg/L, far above the 6 mg/L standard for healthy aquatic life, indicating severe organic pollution.

Anoxic Conditions

Dissolved Oxygen (DO) levels are often near zero, rendering the river incapable of supporting fish or other aquatic species.

Severe Contamination

The river is contaminated with fecal coliform bacteria, heavy metals (such as lead, cadmium, and chromium), and high levels of nitrogen and phosphorus from agricultural runoff and sewage.

This crisis directly impacts the Base of the Pyramid (BoP) population. Farmers are forced to use contaminated water for irrigation, leading to tainted food supplies and health hazards. Local communities, particularly women who are often responsible for water collection and household agriculture, bear the brunt of waterborne diseases and economic hardship.

Communities living alongside polluted river sections

Communities living alongside polluted river sections

Kathmandu Valley site assessment

Kathmandu Valley site assessment

Community education and engagement

Community education and engagement

Training and capacity building

Training and capacity building

The AquaSai Solution: A Nexus-Based Approach

We propose a holistic solution centered on AquaSai's MSR technology—a decentralized, nature-based water treatment system that is cost-effective, energy-efficient, and simple to operate.

Core Technology: Multi-Stage Recirculating Constructed Wetland (MSR)

The pilot project will divert a controlled flow of water from a heavily polluted section of the Bagmati River into a constructed wetland. The system will consist of multiple stages:

Sedimentation Chamber

1. Initial Settling & Screening

Removal of solid waste and large debris through a series of screens and a settling tank, preventing clogging in subsequent treatment stages.

Wetland Bed Cutaway

2. Gravel and Sand Filtration Beds

These beds are planted with a carefully selected polyculture of phytoremediation plants. A microbial biofilm develops on the roots and filter media, breaking down organic pollutants and pathogens.

Recirculation System

3. Recirculation System

Water is recirculated through the stages to enhance aeration and treatment efficiency, significantly increasing DO levels and reducing BOD and COD.

Polishing Pond

4. Polishing Pond

The final stage ensures the removal of remaining pathogens and nutrients before the clean water is discharged. This pond can support aquatic plants and potentially fish, demonstrating the restored ecosystem.

Complete MSR Treatment Process
Vetiver Grass

Vetiver Grass

Chrysopogon zizanioides

This grass develops a massive, fine, and deep root system that is unparalleled for filtering suspended solids and trapping sediment, leading to a dramatic increase in water clarity.

Sediment Filtration
Water Hyacinth

Water Hyacinth

Eichhornia crassipes

A floating aquatic plant known for its rapid growth and incredible ability to absorb heavy metals like lead, mercury, and cadmium, effectively locking them away in its biomass.

Heavy Metal Accumulator
Canna Lily

Canna Lily

Canna indica

A powerhouse of phytoremediation, Canna Lilies have extensive root systems that are highly effective at absorbing excess nitrogen and phosphorus from the water, which are the primary pollutants in wastewater.

Nutrient Removal

Aligning with the Water-Energy-Food Nexus

The Bagmati River Restoration Initiative represents a comprehensive nexus-based approach to sustainable development.

Water-Energy-Food Nexus

(Water) Restoring River Health & Providing Safe Irrigation

Clean water polishing pond

The primary output is treated water that meets Nepal's national standards for irrigation. This will allow local farmers to cultivate safe, healthy produce, breaking the cycle of contamination.

(Food) Enabling Sustainable Urban Agriculture

Water reuse for agriculture

The treated water, rich in plant-available nutrients like nitrogen and phosphorus, is ideal for agriculture. We will partner with local farming cooperatives to establish demonstration plots for high-value crops, promoting food security and increasing farmer incomes.

(Energy) Creating Renewable Energy from Waste

Biomass to Biogas Process

The wetland will be planted with fast-growing species like Napier grass and water hyacinth, alongside native medicinal plants. This biomass will be regularly harvested and fed into a community-scale anaerobic digester to produce biogas for cooking and lighting. The digestate (slurry) will be used as a high-quality organic fertilizer, closing the nutrient loop.

Innovation: Integrating Traditional Medicine and Biodiversity

Plant polyculture in Nepal

A key innovation of our project is the integration of plants from Ayurvedic, Tibetan, and Chinese traditional medicine that are native to Nepal and have known phytoremediation properties. Species like Acorus calamus (Sweet Flag) and Vetiveria zizanioides (Vetiver Grass) will not only help remove heavy metals and other toxins but also provide a source of valuable medicinal products, creating additional income streams for the community.

Community biogas use

Implementation Plan & Budget

We have developed a detailed 24-month plan for the pilot project.

Implementation Storyboard

Phase 1: Setup & Mobilization

Month 1-3: Site selection, community engagement, final design, permits

Phase 2: Construction

Month 4-9: Earthworks, lining, installation of piping & pumps

Phase 3: Commissioning & Planting

Month 10-12: Planting of wetland species, system testing, operational training

Phase 4: Operation & Optimization

Month 13-21: Full operation, water quality monitoring, biomass harvesting

Phase 5: M&E and Scaling

Month 22-24: Impact assessment, business model refinement, outreach

Hands-on training at wetland

Budget Overview

Category Estimated Cost (USD)
Capital Expenditures (CAPEX)
- Construction & Civil Works $85,000
- Pumps, Piping, and Anaerobic Digester $40,000
Operational Expenditures (OPEX)
- Personnel (Project Manager, Technicians) $35,000
- Plant Saplings & Consumables $10,000
- Community Training & Workshops $10,000
- Monitoring, Evaluation & Reporting $10,000
- Contingency (10%) $10,000
Total $200,000

Impact, Scalability, and Sustainability

Impact Metrics

100,000 L
Water Treated Daily
5 Ha
Land Irrigated
50 m³
Daily Biogas Production
10+
Direct Jobs Created
Site plan and impact

Scalability

The modular design of the AquaSai MSR system allows for easy replication and scaling. Upon successful completion of the pilot, we will work with municipalities and development partners (including the ADB and World Bank, with whom we have initiated contact) to replicate the model at multiple locations along the Bagmati and other rivers in Nepal.

Sustainability

The project is designed for long-term financial sustainability. Revenue streams will be developed from:

  • Sales of organic fertilizer and medicinal plants.
  • A "Water Treatment as a Service" model for local industries or municipalities.
  • Potential carbon credits from methane capture and emission reduction.

Conclusion

The Bagmati River Restoration Initiative offers a tangible, high-impact opportunity to address a critical environmental and humanitarian challenge at the heart of the water-energy-food nexus. This initiative will not only restore a sacred river but also cultivate a resilient and prosperous future for the communities that depend on it. We invite you to partner with us in this transformative endeavor.

Contact Us

Get Involved

We welcome partnerships with local communities, government agencies, NGOs, and funding organizations. If you are interested in supporting this initiative or learning more about how you can get involved, please contact us.

  • Email: aquasai@uxrzone.com
  • Address: Kathmandu, Nepal

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