Investigating the effects of climate change on cascaded hydropower system in the Lower Nelson River Basin

The temperature increase in Manitoba is reported to bring shorter winter seasons, heavier winter precipitations and earlier snowmelt periods. The hydropower system in the Lower Nelson River Basin, LNRB located in Northern Manitoba, is a unique combination of storage and run-of-the-river hydropower stations, producing over 70% of province's power generation. An understanding of the projected flow boundary is imperative for future energy security.

Several studies have previously investigated the system response and flow projections in regulated basins by coupling hydrologic and water management models, yet they rarely studied basins with cascaded hydropower stations or run-of-the-river systems. In this research, physically-based hydrologic models (WATLOOD and HEC-HMS) coupled with a water management model (MODSIM-DSS) are used to simulate the future water supply and energy production in LNRB.

The goals of this research are (1) to generate robust flow ensemble bounds by running the coupled models under 19 CMIP5 climate scenarios (representing 90% of climate variability) for a period of 2021-2070 and (2) to estimate the extent of changes in water supply and energy production capacity. The findings of this research aim to support mid-term (~2 year) operation and long-term (~35 year) resource planning by identifying and measuring vulnerability of current operation and planning of LNRB against future conditions.