Hydrologic modeling and evaluation of Best Management Practice scenarios for the Grand River watershed in Southern Ontario

Evaluation of SWAT Impoundment Modeling Methods in Water and Sediment Simulations

“…Based on performance of IR0, it would be expected that if the IRESCO_3 method was applied in all three lakes, sediment yield underestimation would be even more pronounced. Additional studies by Liu et al (2016) (using daily data) documented good and very good statistical ratings in streamflow simulation, and overall satisfactory results in sediment and nutrient simulation. The study included calibration of nutrient-related impoundment parameters and simulated the streamflow well.…”

“…The Measured Monthly Outflow Method with impoundment nutrient parameters calibration was also a method used by Zhang et al (2011) (with IRESCO_0), and resulted in good simulation of streamflow and satisfactory simulation of ammonium and chemical oxygen demand. Additional studies by Liu et al (2016) (using daily data) documented good and very good statistical ratings in streamflow simulation, and overall satisfactory results in sediment and nutrient simulation. Similar outcomes were reported by Ouyang et al (2011) (using monthly data) in a study where streamflow was simulated very well, while results of sediment simulation (sand only) were unsatisfactory and nutrient simulation was satisfactory.…”

“…(1) fraction of 1; (2) fraction of 0.5; (3) proportional, where the fraction is a proportion of the wetland area, divided by area of the subbasin (Almendinger and Murphy (2007); Liu et al 2016); and (4) true (measured) fraction, where the area of subbasin contributing to the wetland was measured based on the delineated stream network and topography of the wetland inlet (a fraction of 0.7) and outlet (a fraction of 0.9). The change in pond and wetland fraction is proportional to the amount of sediment routed through wetlands and ponds (Figure 7).…”

“…In previous studies, SWAT ITs were used to model a constructed wetland placement effect on water quality (Wang et al 2008); wetlands' influence on flood mitigation, peak-flow reduction through wetland water retention, and increased evapotranspiration (Demissie and Khan 1993;Hattermann et al 2006;Babbar-Sebens et al 2013); and to simulate nutrient retention in natural and constructed wetlands (White and Bayley 2001;Vache et al 2002;Cooper 2009). SWAT ITs were also used to estimate sediment and nutrient retention in reservoirs (Mishra et al 2007;Bosch 2008;Liu et al 2014); to assess dam and check dam impact on local water, sediment, and nutrient yields (Mishra et al 2007;Ouyang et al 2011;Zhang et al 2011;Liu et al 2014;Norman and Niraula 2016); to model reservoir placement feasibility (Zhang et al 2012); to calculate reservoir water availability for municipal purposes (Brauer et al 2015); and to model and account for reservoir influence in SWAT modeling (Kirsch et al 2002;Bosch 2008;Wang and Xia 2010;Liu et al 2016;Vigiak et al 2016).…”

Can Improved Flow Partitioning in Hydrologic Models Increase Biogeochemical Predictability?

“…Table B1 elaborates on different variables and calibration parameters (and their prior range) associated to the nitrate module, which are also used in the equations provided in this appendix. Regarding fertilizer application, due to unavailability of detailed field survey data, we estimated a constant year-integrated amount of fertilizer based on a previous modeling work in the Grand River watershed (Liu et al, 2016), who reported time-dependent fertilizer application based on literature. Fertilizer is applied uniformly during the first two weeks of May in each year only to agricultural HRUs (i.e., no fertilizer was considered in forest HRUs).…”