Colonia Valley, Patagonia – April 2016

During April 2016 project collaborators from the Austral University of Chile travelled to the Colonia Valley, located southeast of the Northern Patagonia Icefield. Since 2008, the Colonia Valley has been affected by more than 15 GLOFs when the ice-dammed lake Cachet 2 started a GLOF cycle. The aim of the field campaign was to carry out a topographic survey (using a DGPs) of parts of the Colonia Valley, collecting data concerning the extent and depth of these recent outburst floods. This dataset will help towards calibrating hydrodynamic models which will be used to simulate past and future GLOFs in the Colonia Valley. With the most recent GLOF event having occurred several months ago, the mapping of the maximum flood extent using only sedimentary evidence proved challenging. Fortunately, however, local inhabitants of the Colonia Valley were welcoming and helped identify areas inundated by the recent flood. These initial observations revealed considerable differences between the extent of the Colonia River during normal flow conditions for April and at peak discharge during a GLOF event (see images below).