Quail Creek SWAT Simulation using ArcSWAT

This study used the SWAT model to simulate streamflow into the Quail Creek Reservoir, covering a 48,500-acre catchment in Southern Utah. The model was calibrated using flow data from the Leeds Creek gage (USGS ID: 09408000), representing a portion of the catchment. Key inputs included elevation data from USGS, land cover from the 2021 NLCD, and soil data from FAO, with weather data sourced from PRISM (1981–2023). Critical parameters such as CN2, ALPHA_BF, and SOL_K were calibrated to improve flow predictions. The model achieved an NSE greater than 0.6, somewhat accurately capturing seasonal flow patterns. In addition, a comparative analysis was conducted between the SWAT model and StreamStats-generated flow data. The results showed that SWAT performed better than StreamStats, producing lower errors and more accurate representations of observed streamflow, particularly during peak flow events. Despite some limitations due to modeled weather data, the SWAT simulation provided valuable insights into the region's hydrology and supports future water management efforts.
Model: Soil and Water Analysis Tool (SWAT) in ArcSWAT (ArcMap 10.8)
Performance: NSE & R2 > 0.6
Channel Routing Method: Variable Storage
Potential Evapotranspiration (PET) Method: Penman-Monteith
Rainfall-Runoff Method: Daily Rain/CN/Daily Route
Initial Condition: Soil-Moisture
Total Run: 49 iterations with 2,000 runs per iteration (98,000 total runs)