Surge Flow CFD at the Curah Lengkong Valley, Semeru Volcano, Indonesia

The Curah Legnkong valley on the Southeast flank of Semeru Volcano is regularly the scene of lahar flows, during and after which valley side collapses occur recularly. Such collapses happen in the lahar deposits themselves but also from lava-flow deposits that collapse in the valley. In the case of a large natural dam, it could result in the temporary blockage of the valley resulting in potential catastrophic flooding. In the present contribution, the author presents an investigation of potential breakout floods using a flood scenario at 300 m 3.s-1 instantaneous discharge.