Analysis and modelling of recent large floods on the river Gaula

Abstract

In order to study the flood from 2009, 2010 and 2011 that have been impacting the Gaula waterway, a hydrological and operational model have been built. A brief description of the study is given as an introduction, followed by the description of the study place which is located in Midtre Gaudal in Sør Trondelag, it comprises of four (04) unregulated catchments being Gaulfoss the biggest and the rest of them being part of Gaulfoss. Daily and Hourly data have been collected, analyzed and formatted so they can be compatible with ENKI platform. Once the model is set and the parameters assigned, the calibration can be started. While processing the results it was possible to see that even though R2 was the simulated discharge was not meeting the aforementioned floods. An exercise has been made by using radar data and scale the precipitation value and evaluate how much does this affects the model. As a second part of the study, the hydropower system developed in Samla Plan (Habberstad, 1984) was used to build an operational model in nMag to see how good this system would have work with the mentioned floods. Discussions, comments and conclusions included in the study.