Modeling Groundwater Level Fluctuation in the Tropical Peatland Areas under the Effect of El Nino

This research aimed to model groundwater level (GWL) fluctuation in the tropical peatland areas under the effect of El Nino Southern Oscillation (ENSO). The focus of the study was the peatland area between Sebangau River and Kahayan River, Central Kalimantan Province Indonesia. One-dimensional GWL model was developed using Excel in order to simulate the GWL fluctuation of 4 GWL observation wells which were Swtr2, Swtr3, Swtr4, and Swtr6. The model was calibrated for the dry season 2011 and, after that, was used to model GWL fluctuation in El Nino year of 1997 and 2002. The model showed very good performance in simulating GWL fluctuation of 4 observation wells in the dry season condition where the GWL were under the ground level elevation. The model indicated that in the El Nino years of 1997 and 2002, the GWL in the observed area in the dry season dropped significantly due to the absence of rainfall in the area. Based on the model, the fire risk in the tropical peatland areas can be measured and predicted.