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Ramcha rasuwa District 

Ramche landslide on Trisuli-Dhunche road of Rasuwa district is one of the longest landslides in the country stretching to 36 kilometers. It was first launched in 1983 and recactivated on the night of August 14, 2003 when 23 army officers on duty at the site perished.  

Geologically, the landslide is located on the southern limb of the Kuncha-Gorkha anticlinorium with the sequence of meta sandstones and chlorite phyllite. A wedge shaped body created by joint and foliation has trapped as much as 30m of gravely, fine sandy, and bouldery colluvium. The bedrock outcrops both at the head and the toe of the slide with the motor road crossing the slide area. 

- **Water Diversion**: Irrigation has also increased infiltration where water from streams is diverted over the colluvium.

- **Road Excavation**: This has been further supplemented with construction activities of roads for development of infiltration.

- **Impermeable Phyllites**: Soil absorption characteristics have also been altered by the normally impermeable but highly impermeable Kuncha phyllites at the base of the colluvium limit the dissipation of excess pore water pressures within the soil.

- **Traffic Vibrations**: The vehicle traf c has now enhanced vibrations that have enhanced downslope movements of debris along the rock surface.

Landslide movement is more during the monsoon period and the area is least active in winter with moving rates of more than one metre per annum. This constant instability has created surface cracks in the houses: They have been wrecked; 16 houses in Polchet Village with over 100 people and their stocks in danger of being buried alive. Similarly, the two high tension poles of the Chilime hydropower project and the 36 km sectional Trisuli-Dhunche road has been slipped off. 

However, based on the latest available data, there were no efforts made to halt the subsequent slope failure or to save the lives of the inhabitants of Polchet. Based on the research, it would be inferred that better drainage control along with non- rice cultivation techniques might help reduce pore-water pressure over the land. Nevertheless, as in all such situations, before implementing some form of prevention, further classification is needed. 

In general terms, landslides have always been a perpetual threat to the Nepalese territory particularly owing to the following causative factors; the monsoon season rain, the seismic factor and the haphazard structural development on the land. For instance on 2nd of December, 2014, a big learnt at Arukharka VDC Sindhupalchok district, which claimed 156 lives and Constructed Koshi River. 

Disaster such as landslides in Ramche need a large scale work, started with geophysical surveys, rigid polices to address the anthropogenic activities that leads to land slides and sound disaster risk reduction measures to protect the vulnerable people and investments.