Environmental flow assessment in the context of climate change: a case study in Southern Quebec (Canada)

Abstract

Through a case study in Southern Quebec (Canada), the assessment of environmental flows in light of the effects of climate change is investigated. Currently, the 7Q2 flow metric (7-day average flow with a 2-year return period) is used for water abstraction management. Several flow metrics were calculated using flow time series simulated by a deterministic hydrological model (HYDROTEL) and climate change scenarios as inputs. Results were compared within homogeneous low flow regions defined using ascendant hierarchical clustering, for the 1990, 2020 and 2050 horizons and annual, summer and winter periods. The impact of each flow metric on the potential availability of physical habitat was analyzed using the wetted perimeter as a proxy. Results indicated that: (1) the increasing non-stationarity of simulated flow data sets over time will complicate the use of frequency analysis to calculate the 7Q2 flow metric; (2) summer low flow values are expected to be lower than winter low flows; and (3) flow-duration curve metrics like the LQ50 (median discharge value of the month with the lowest flow) may become relevant environmental flow metrics by 2050. Results question current water abstraction management tools and permit to anticipate future local and regional issues during low flow periods.

Impact of Reservoir Operation Policies on Spatiotemporal Dynamics of Sediment Methane Production and Release in a Large Reservoir

“…This led to the protection of downstream ecosystems through the release of environmental flows, which has subsequently become an important target of reservoir operations, promoting the development of the eco‐friendly operation policy (EOP). Various environmental flow assessment and management methods have been proposed with respect to different ecological targets (e.g., Berthot et al., 2021; Richter et al., 2012; Stein et al., 2021). As a case study, we select a comprehensive EOP that accounts for the protection of multiple ecosystem functions (Yin et al., 2012).…”

Extension of a Monolayer Energy-Budget Degree-Day Model to a Multilayer One

“…It encompasses phenomena found in simple models like CEMANEIGE and HBV (i.e., snow accumulation and melting), as well as numerous phenomena typically associated with multilayer modeling approaches (e.g., convective heat, precipitation heat, soil heat, compaction, mixing, radiation heat/melting degree-day, water retention). HYDROTEL [9,10] is the semi-distributed hydrological model at the core of operational hydrologic forecasting systems in the Quebec [11,12], Yukon [13][14][15], and Southern Québec Hydroclimatic Atlas [16][17][18], as well as in several other studies, such as on the effect of global warming on environmental flows [19][20][21] or the role of wetlands on mitigating floods and droughts [22][23][24]. These applications are made in a Canadian context, where most watersheds are subject to significant snowfall.…”

Extreme Hydrological Drought in Southern Quebec (Canada): Natural and Anthropogenic Factors Interactions on its Spatio-Temporal Variability

“…Several studies have already been devoted to the analysis of minimum flows in Quebec. But all these studies were mainly limited to the analysis of these flows at seasonal scales [11][12][13][14][15][16][17]. As for the annual scale, a few pan-Canadian studies have already analyzed the spatial and temporal variability of minimum flows [18][19][20][21][22].…”