Dynamic modelling of the impact of climate change and power flow management options using STELLA: Application to the Steephill Falls reservoir, Ontario, Canada

Abstract

This paper presents a dynamic modelling framework for evaluating the impact of climate change and flow management options on a hydroelectric power reservoir. The model couples the HBV (Hydrologiska Byråns Vattenbalansavdelning) rainfall-runoff model to a generic reservoir routing model. The efficacy of the model was tested on the Steephill Falls hydropower facility located in the Magpie River watershed in Northern Ontario. Both the impact of climate change and future energy demands were evaluated. Using a statistical downscaling approach, future climate under Intergovernmental Panel on Climate Change (IPCC) A1B and A2 emission scenarios was projected from the Canadian Global Circulation Model 3 (CGCM3). Both scenarios suggest a significantly increasing trend in air temperature (p < 0.001) corresponding to a 1.7°C increase by the middle of the century and a 2.9°C to 3.7°C increase by the end of the century relative to the baseline period (1970-2000). The model performed well in simulating the inter-annual seasonal dynamics of the reservoir. Plausible climate-induced increase in runoff input into the reservoir might be counterbalanced by increased drawdown caused by increasing energy demands and water users, resulting in increased pressure to adjust lower reservoir rule curves, in-stream flow requirements downstream, or a combination of both. © 2012 Canadian Water Resources Association.