Heavy and prolonged rainfall in the catchment of Alaknanda river and Khirao Ganga  brought down huge debris material. Khirao Ganga had blocked the course of  the Alaknanda river and created an artificial lake for some time. This was breached later on by
An Interim Report on Preliminary  Geological  Slope Stability Assessment of the Recent Disaster Affected Areas in Parts of Chamoli District, Uttarakhand by Bhupendra Singh, Bhupender Singh, Ajay Kumar and Arindam Roy, Senior Geologists, M-IV, NR GSI Dehr
UK_CHA_NH_ 056
About 100m upstream of JP Vishnuprayag barrage
Removal of overhangs, toe protection upto HFL, slope dressing by benches, breast wall with weep holes and lined toe drain.
Heavy rainfall in catchment of Alaknanda River caused flash flood and toe erosion triggering movement of debris. Heavy rainfall also saturated the terrace and colluvial material causing loss of shear strength.