Proceedings of the 2023 Mississippi Water Resources Conference

Year: 2023 Authors: Bhattarai S., Parajuli P.B., To F.

In this study, the variation in streamflow due to climate change was assessed at two coastal watersheds: Wolf River Watershed (WRW) and Jourdan River Watershed (JRW) of Mississippi. The Soil and Water Assessment Tool (SWAT) model was used to simulate the hydrology of WRW and JRW. Further, the flood frequency of the simulated peak flow events was analyzed. The baseline models for both watersheds were auto-calibrated with SWAT-Calibration and Uncertainty Programs (SWAT-CUP). Kling-Gupta Efficiency (KGE) ranges from 0.8 to 0.7 in WRW and from 0.55 to 0.68 in JRW during model calibration-validation. Results in WRW indicated that the monthly average baseline flow was 1% greater than historical and 8.88% less than future climate. Likewise, monthly average baseline flow was 10.9% greater than historical and 5.73% less than future climate in JRW. Annual maximum series and partial distribution series of all climatic conditions were fitted to Log-Pearson Type-III distribution to analyze and compare flood frequency. Thus, this study could support watershed managers and planners to prepare for flood occurrence likelihood in the future.