Mitigation measures of erosion

Erosion is the detachment and removal of soil and rock by water, wind or ice. In Nepal, water erosion on steep, cultivated and deforested slopes and river bank erosion are the main problems. The mitigation measures are:

1. Vegetative (bio-engineering) measures: afforestation, grassing, shrub planting, brush layering and live fascines to bind soil and reduce raindrop impact.
2. Agronomic and land-use measures: contour farming, mulching, crop rotation, strip cropping, controlled grazing and avoiding cultivation on steep slopes.
3. Terracing: bench terraces and bunds to reduce slope length and runoff velocity.
4. Drainage control: surface drains, cut-off drains, diversion channels and energy dissipaters to carry runoff safely off the slope.
5. Structural measures: check dams in gullies, gabion walls, retaining walls and sub-surface drains.
6. River bank protection: riprap, gabion revetments, spurs/groynes, embankments and bank vegetation.
7. Slope grading: cutting stable slope angles and covering bare slopes with geotextile or jute netting.
8. Awareness and regulation: community forest management and watershed management.