Economic Assessment of Best Management Practices in the Mara River Basin: Toward Implementing Payment for Watershed Services

摘要

The Mara River in East Africa is currently experiencing poor water quality and increased fluctuations in seasonal flow. Improved water quality will require upstream farmers and foresters to adopt Best Management Practices (BMPs), which might cost them considerably. This study proposes a Payment for Watershed Services (PWS) mechanism. This is a market-based approach, whereby downstream water users would pay upstream watershed service providers towards the costs of BMPs implementation. This study analyzes the technical feasibility and economic viability of adapting selected BMPs and provides cost estimates of a PWS program. Using three criteria of water quality improvement, economic feasibility, and technical suitability, a detailed economic opportunity cost analysis revealed that farmers would indeed incur economic losses for all BMPs except no-till fanning. We also developed a multi-criteria (demographic and environmental) methodology for identifying land areas to be placed under BMPs. More than 122,000 ha of land would require BMPs, including a moratorium on agriculture inside the Mau Forest Complex. The initial per hectare opportunity costs across the five highest ranked BMPs ranged from US$ 272 to US$ 926. Using these cost estimates, the paper draws some valuable policy and management insights on how to finance BMP implementation.