世界银行-莱索托道路集水区气候风险和脆弱性评估：莱索托道路脆弱性评估工具的开发和选定集水区的脆弱性评估（英）-2023-98页_17mb

Report Summary: Climate Change Risk Assessment for Roads in Lesotho

1. Background & Context

• The Kingdom of Lesotho faces significant challenges from climate change, including increased rainfall intensity and temperature fluctuations.
• Road degradation is driven primarily by inadequate protection, poor maintenance, and catchment erosion due to climate change and land mismanagement.
• The National Strategic Development Plan (NSDP II) emphasizes climate-resilient infrastructure, but current road design standards and maintenance practices are insufficient.

2. Key Findings

• Climate Impacts: Climate change exacerbates existing road risks by intensifying flooding, erosion, and infrastructure failure.
• Catchment Linkages: Road issues are intrinsically tied to catchment health:
  • Unprotected drains & riverbanks (Issue Theme 1) lead to gully formation and road damage.
  • Slope instability (Issue Theme 4) and borrow pits (Issue Theme 6) increase during heavy rains.
  • Community-built roads (Issue Theme 11) often use poor-quality materials and lack technical support, leading to rapid deterioration.
• Land management is another key driver (Issue Theme 13), with unsustainable farming practices increasing runoff.

3. Recommendations for Climate-Resilient Roads

• Upgrade infrastructure: Use 900mm culverts, design for higher flood loads, and add paved shoulders.
• Community Engagement: Train communities in proper road construction and maintenance using NbS and techniques like contour bunds.
• Integrate catchment management: Align road projects with Catchment Management Plans (CMPs), supported by institutions like ReNOKA.
• Establish institutional support: Appoint "road extension officers" for technical guidance.