Institute: North Dakota
Year Established: 2019 Start Date: 2019-06-01 End Date: 2020-05-31
Total Federal Funds: $5,500 Total Non-Federal Funds: $11,000
Abstract: Modeling of overland flow on depression-dominated surfaces is challenging due to the spatial distribution of depressions. Moreover, the hierarchical relationships between depressions and their contributing areas make the hydrologic modeling even more complicated. The objective of this 1-year project is to develop a puddle-based-unit (PBU) oriented SWAT (SWAT-PBU) model to simulate the influence of spatially distributed depressions on hydrologic processes. The SWAT-PBU will be applied to a depression-dominated site in North Dakota. In the SWAT-PBU, to consider the influence of depressions, each subbasin is divided into channel-based units (CBUs) and PBUs by using the Depression-Dominated Delineation (D-cubed) algorithm. CBUs are non-depressional areas and surface runoff from these areas is simulated by using the SCS-CN method in the original SWAT. For PBUs (depressional areas), however, a PBU-based probability distribution model (PDM) will be developed to determine the depression storage of PBUs at each simulation time step. In addition, each subbasin is further analyzed to develop the relationships of depression storage, contributing area, and outlet discharge. Finally, these relationships and the proposed PBU-based PDM will be integrated into SWAT to facilitate hydrologic modeling for depression-dominated areas. The applicability of the SWAT-PBU model will be assessed by the application to a depression-dominated site in North Dakota. The new method is useful for improving hydrologic modeling for landscapes of topographic depressions and effectively predicting hydrologic extremes (e.g., flooding).