Noklak landslide threatens 1.84 sq. km, one-fifth of town's population

It matters to citizens as it provides technical evidence regarding the instability of the slope affecting the town's infrastructure and population.

Who it concerns: Residents of Noklak town in Tuensang District, Nagaland; researchers from the Department of Geology at Nagaland University; and the public affected by the landslide covering 1.84 sq. km.

What the document says

• The study identifies the Noklak landslide as a complex instability affecting 1.84 sq. km, threatening nearly one-fifth of the town's population and the route to the International Trade Centre at Pangsha.
• Kinematic analysis of 1,195 joint attitudes indicates both planar and wedge type failures, with several micro-slips and an absence of firm bedding.
• Rock Mass Rating (RMR) and Point Load Test (PLT) data indicate poor rock quality and low strength values for the rocks in the area.
• Slope Mass Rating (SMR) values for the slope fall in Class IV, which is described as 'Poor' rock and 'Unstable' stability.
• The landslide initially started in 1980 and was reactivated in 2004, with subsequent failures in succeeding years.

Also in the document

• The area is characterized by weak lithology and an average slope of about 50 degrees.
• The study utilized data from 50 rock samples collected from four locations for compressive strength determination.
• The location is incorporated in Survey of India (SOI) topographic sheet no. 83 N/4.