Himalayan population at earthquake risk: Strategies for preparedness

Abstract

Purpose

Seeks to examine risk assessment of human settlements due to seismo‐tectonic setting of a populated area in the Himalayas, so that mitigation measures may be taken before the next earthquake takes its toll.

Design/methodology/approach

Keeping in view the seismic vulnerability of the Himalayan ranges, an earthquake scenario is considered for the Narendranagar block of Tehri Garhwal District which lies in Seismic Zone IV of the seismic zoning map of India (BIS, 1893‐2002). Damage of MSK Intensity VIII and peak accelerations of 0.25 g are expected here at any time. The hypothetical epicenter is placed near Tapowan at 30°08′10″N and 78° 20′30″E on the crest of the meandering River Ganga, where three large thrusts, viz. Garhwal, Tons Nayar and Krol, congregate. Iso‐acceleration contours plotted for the entire Narendranagar block for earthquakes of magnitude 7.0 and 7.5 are elongated along the main boundary fault.

Findings

Almost 59 percent population of the Narendranagar block was found to be vulnerable to damage associated with higher accelerations of 0.41 g.

Research limitations/implications

The topographic effects influencing the risk of settlements have not been taken into account.

Practical implications

Implications of such an earthquake on housing stock; roads; infrastructure; awareness and time of occurrence are discussed. Strategies are suggested for long‐term earthquake preparedness and short‐term action plan for emergency management.

Originality/value

The methodology evolved can be extended for other Himalayan regions.

Citation

Gupta, I., Sinvhal, A. and Shankar, R. (2006), "Himalayan population at earthquake risk: Strategies for preparedness", Disaster Prevention and Management, Vol. 15 No. 4, pp. 608-620. https://doi.org/10.1108/09653560610686568