Groundwater contribution to river flows – using hydrograph separation, hydrological and hydrogeological models in a southern Quebec aquifer

Abstract

Abstract. Groundwater contribution to river flows, generally called base flows, often accounts for a significant proportion of total flow rate, especially during the dry season. The objective of this work is to test simple approaches requiring limited data to understand groundwater contribution to river flows. The Noire river basin in southern Quebec is used as a case study. A lumped conceptual hydrological model (the MOHYSE model), a groundwater flow model (MODFLOW) and hydrograph separation are used to provide estimates of base flow for the study area. Results show that the methods are complementary. Hydrograph separation and the MOHYSE surface flow model provide similar annual estimates for the groundwater contribution to river flow, but monthly base flows can vary significantly between the two methods. Both methods have the advantage of being easily implemented. However, the distinction between aquifer contribution and shallow subsurface contribution to base flow can only be made with a groundwater flow model. The aquifer renewal rate estimated with the MODFLOW model for the Noire River is 30% of the recharge estimated from base flow values. This is a significantly difference which can be crucial for regional-scale water management.

Defining parameters for Eckhardt's digital baseflow filter

“…Digital filters use only streamflow data to estimate the base flow and have shown good results when compared to other techniques by Arnold and Allen (1999) and Larocque et al (2010). Several digital filters have been proposed in the last decades.…”

Understanding Hydrological Variability for Improved Water Management in the Semi-Arid Karkheh Basin, Iran

“…The BFI estimates were used to characterize the base flow contribution to the streamflows and as well as its spatiotemporal variability. Further details on base flow analysis and some of its applications can be found at Nathan and McMahon (1990a), Arnold and Allen (1999), Larocque et al (2010) and Welderufael and Woyessa (2010).…”

The examination of the performances of methods used in separating the total stream flow in different rivers

“…According to the literature the models developed for this purpose give good results (Arnold and Allen, 1999;Larocque et al, 2010). In addition, the most significant issue to be paid attention in the processes of separating the flow into components is to test the accuracy of the methods.…”