Mitigation of geological problems in Himalaya

Geological problems of the Himalaya arise from its young tectonics, weak and fractured rocks, steep slopes and monsoon rains. Mitigation measures are:

1. Detailed geological investigation before construction: mapping, geophysical surveys, boreholes and hazard zoning, avoiding active faults, unstable slopes and landslide-prone ground.
2. Slope stabilisation: reduce slope angle, benching, remove loose material, retaining and breast walls, gabions, rock bolts, anchors, wire mesh and shotcrete.
3. Drainage control: surface drains, catch drains, sub-surface drains and horizontal drains to lower pore pressure.
4. Bio-engineering: vegetation, grass and tree plantation to bind soil and reduce erosion.
5. River and flood control: embankments, spurs, check dams, river training, and monitoring of glacial lakes (lowering lake level, early warning systems).
6. Earthquake resistant design following the Nepal Building Code and keeping structures away from active faults.
7. Tunnel support: systematic classification and flexible support in squeezing and weak zones.
8. Monitoring and early warning, land-use planning and community awareness.
9. Afforestation and control of unplanned road cutting.