Modelling Chorabari Lake outburst flood, Kedarnath, India

Abstract

In this study, the Glacier Lake Outburst Flood (GLOF) that occurred over Kedarnath in June 2013 was modeled using integrated observations from the field and Remote Sensing (RS). The lake breach parameters such as area, depth, breach, and height have been estimated from the field observations and Remote Sensing (RS) data. A number of modelling approaches, including Snow Melt Runoff Model (SRM), Modified Single Flow model (MSF), Watershed Management System (WMS), Simplified Dam Breach Model (SMPDBK) and BREACH were used to model the GLOF. Estimations from SRM produced a runoff of about 22.7 m3 during 16–17, June 2013 over Chorabari Lake. Bathymetry data reported that the lake got filled to its maximum capacity (3822.7 m3) due to excess discharge. Hydrograph obtained from the BREACH model revealed a peak discharge of about 1699 m3/s during an intense water flow episode that lasted for 10–15 minutes on 17th June 2013. Excess discharge from heavy rainfall and snowmelt into the lake increased its hydrostatic pressure and the lake breached cataclysmically.