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Sub-Saharan Africa's Urban Water Blueprint Summary

Core Content

This report, Sub-Saharan Africa's Urban Water Blueprint: Securing Water Through Water Funds and Other Investments in Ecological Infrastructure, published by The Nature Conservancy in August 2016, outlines the critical role of source catchments in urban water security and highlights the potential of ecological infrastructure and water funds to address water challenges in the region.

Main Points

• Urban Water Demand: Africa's urban population is expected to double in the next 20 years, increasing pressure on water resources.
• Water Source Vulnerability: Many cities in Sub-Saharan Africa (SSA) source their water from surface water, with three-quarters of large cities relying on at least half of their supply from surface sources, totaling an estimated 3.5 billion cubic meters annually.
• Catchment Importance: Source catchments are vital for water security, and their degradation affects both water quality and quantity, leading to increased treatment costs and reduced water availability.
• Land Use Impact: Land use changes, particularly agricultural expansion, significantly impact water quality and ecosystem services. On average, 38% of catchment areas are used for agriculture, affecting 85 million people.
• Pollution Risks: One-fifth of source catchments may be impacted by high sediment or nutrient loads, threatening 17 million urban residents and aquatic biodiversity.
• Economic Costs: Degradation of catchments leads to substantial financial costs for cities, including increased water treatment expenses and reduced hydropower capacity.
• Ecological Benefits: Catchment protection supports biodiversity, wildlife habitats, and rural livelihoods, with 5.8 million hectares of priority biodiversity areas at risk.
• Water Funds Model: A collaborative and sustainable financing mechanism that enables cities, businesses, and governments to invest in catchment conservation, offering significant returns in terms of water security and environmental protection.
• Case Study: The Upper-Tana Nairobi Water Fund demonstrates how catchment protection can reduce sedimentation and improve water quality, leading to lower treatment costs and better infrastructure performance.
• Infrastructure Investment: Some cities have reduced water stress through infrastructure expansion, such as inter-basin transfers, but these are costly and not feasible for all.
• Future Challenges: As cropland is expected to expand globally in Africa by 2050, there is an urgent need for smarter land management practices to balance urban growth and environmental sustainability.

Key Information

• Cities and Catchments: 30 cities in SSA are primarily dependent on surface water sources, drawing from 84 catchments covering over 67 million hectares.
• Water Security Risks: Over 17 million people in cities reliant on surface water may face water security risks due to degraded catchments.
• Conservation Potential:
  • 28 cities can benefit from conservation actions that reduce sediment and nutrient loads.
  • 16 cities could see treatment costs offsetting at least 25% of conservation expenses.
  • Half of these cities could potentially offset the entire cost of catchment conservation through avoided treatment costs.
• Agricultural BMPs: These practices, such as terraces and cover crops, offer the broadest applicability and benefit 85 million people.
• Forest Protection: Can reduce pollution and benefit up to 52 million people.
• Riparian Restoration: Benefits up to 11 million people.
• Water Fund Success: The Nature Conservancy has established over 60 water funds globally, with 30 in SSA, offering a scalable and effective model for sustainable water management.

Conclusion

The report emphasizes the need for integrated, sustainable approaches to managing water sources in Sub-Saharan Africa. By investing in ecological infrastructure and implementing water funds, cities can secure water supplies, reduce treatment costs, and support biodiversity and rural livelihoods. This model is critical for addressing the growing water challenges in the region, especially as urbanization and climate change continue to impact water availability and quality. The findings highlight the importance of protecting upstream catchments to ensure long-term water security and environmental health for both urban and rural populations.