SWAT modeling of hydrology, sediment and nutrients from the Grand River, Ontario

Abstract

The Grand River watershed (GRW) is an important agricultural area in Southern Ontario. Land use has been modified by various human endeavors, altering hydrology and increasing export of sediment and nutrients. The objective of this study was to predict spatial and temporal patterns of hydrology, and export of sediment and nutrients from the GRW to Lake Erie using the Soil and Water Assessment Tool (SWAT) model. The Sequential Uncertainty FItting (SUFI2) program was used to calibrate and validate stream flow for years 2001–2010. Calibration and validation of the SWAT model for monthly stream flow at York indicated good model performance (R2, NSE, and PBIAS = 0.64, 0.63 and 7.1 for calibration (2001–2005); = 0.82, 0.74 and 0.2, for validation (2006–2010)). The model was applied to predict sediment and nutrient export from the GRW into Lake Erie. Predicted loading at Dunnville (near the mouth) was 2.3 × 105 tonnes y−1 total suspended sediment, 7.9 × 103 tonnes y−1 TN, and 2.3 × 102 tonnes y−1 TP. This SWAT model can now be used to investigate the relative effects of best management practices, and to forecast effects of climate change, on sustainable water management, hydrology, and sediment and nutrient export to Lake Erie.

Effects of local land-use policies and anthropogenic activities on water quality in the upstream Sesan River Basin, Vietnam

“…SWAT description. SWAT is a well-known physical-hydrological model used to predict the impact of land-use changes and land management practices on river discharge (Hanief and Laursen, 2017), sediment (Shi and Huang, 2021), and nutrients (Epelde et al, 2015;Donmez et al, 2020) over long periods on the river basin scale. The hydrological cycle in SWAT is based on the water balance equation, in which surface runoff is estimated through the SCS curve number equation as follows:…”

Modeling the Natural Drainage Network of the Grand River in Southern Ontario: Agriculture May Increase Total Channel Length of Low-Order Streams

“…A Soil and Water Assessment Tool (SWAT) model has been recently developed for the Grand River Basin. This model is described, along with calibration and validation for the prediction of discharge and export of sediments and nutrients from the GRW [20]. Because it is a physically-based model, SWAT provides the unique opportunity to simulate the hydrology and water quality of ungauged streams and to quantify the relative impacts of alternative input data on hydrology and water quality in watersheds.…”

“…The model was run on a monthly scale for four different scenarios: (a) 10-m DEM using the ground-truthed stream network (referred to as a comparator), (b) 10-m DEM using ArcSWAT for stream delineation, (c) 25-m DEM using ArcSWAT for stream delineation and (d) 200-m DEM using ArcSWAT for stream delineation. Manual calibration of streamflow and sediment discharge was done using parameters as outlined in a SWAT model for the GRW that has been constructed, calibrated, and validated for prediction of water discharge, sediment transport and phosphorus transport [20].…”

“…Such activities come at cost, and it is important to first define what impact such targeted efforts in these relatively small stretches of the watershed might have on water quality. Recently, a SWAT model for the GRW was constructed, calibrated, and validated for prediction of water discharge, sediment transport, and phosphorus transport [20]. This model can provide an effective tool for future testing of the application of Best Management Practices to these extended headwater channels, to reduce sediment and nutrient transport.…”

Spatial-Temporal Response of Sediment Loads to Climate Change and Soil Conservation Practices in the Northern Aegean Watershed, Türkiye

“…Hydrological conditions and erosion vary depending on changing environmental conditions that are also affected by numerous factors such as changes in land use, agricultural practices, and the climate crisis [1,2]. Therefore, changes in cloud microstructure, solar radiation, precipitation, and temperatures due to the climate crisis and intensification of agricultural practices cause an increase in nutrient materials such as nitrate and phosphorus in water resources [3][4][5]. These situations cause changes in basin hydrology and ecological functions.…”