Assessment of the current state of process-based watershed models to support adaptive management

Session: Applications of Simulation Models in Watershed Science and Lake Ecology (1)

Feifei Dong, University of Toronto, [email protected]
Alex Neumann, University of Toronto Scarborough, [email protected]
Dong-Kyun Kim, University of Toronto Scarborough, [email protected]
George Arhonditsis, University of Toronto Scarborough, [email protected]

Abstract

This study aims to evaluate the strengths and weaknesses of contemporary process-based watershed models. We briefly review the hydrologic, sediment and nutrient components of eleven most frequently used empirical and physically-based watershed models. Mathematical equations, assumptions, data requirements, and applicability of the candidate physically-based watershed models are investigated. We assess their capabilities to reproduce hydrological, nutrient fate and transport mechanisms within agricultural and urban environments, and relate the model performance to their ability to evaluate Best Management Practice (BMP) efficiency. Constraining simulated in-stream fluxes of water and waterborne constituents may be improved by incorporating information from a greater variety of locations in space. We argue that calibrating a distributed, process-based model to multiple stations within a nested basin context can reduce the uncertainty of the water quality predictions and also improve the accuracy at the upstream stations Other on-going issues to further advance the existing models are the explicit consideration of the risks of sub-optimal performance with the evaluated conservation strategies, the representation of the role of legacy P, and the development of a weighting scheme to impartially synthesize the individual predictions when multiple models are applied in a given catchment.