Hydrodynamic relationships between gravel pit lakes and aquifers: brief review and insights from numerical investigations

Abstract

Supply of aggregate materials for every construction requires mining of sand and gravel, which leads to the formation of a myriad of freshwater lakes, a now common feature of the landscape in the valleys of large rivers. Typically small in size and shallow, they are filled with waters from the adjacent aquifers and directly exposed to the atmosphere. The creation of gravel pit lakes has various and contrasting effects on their immediate environment. This article first provides a review of these impacts from the hydrodynamic point of view, and illustrates them on simple numerical test cases. It also introduces the gravel pit lake module developed for the occasion within the integrated modelling platform CaWaQS, which formulation was tested on the same test cases against the Lak package, its Modflow counterpart. By accurately simulating gravel pit lake interactions with groundwater in different configurations, this modelling exercise also aims to identify the preponderant factors leading water level fluctuations of those artificial lakes, whose temporal monitoring will soon be accessible to satellite observation.

Effects of a Gravel Pit Lake on Groundwater Hydrodynamic

“…The Dupuit-Forchheimer assumptions are described in Section 2. In addition to the thickness of the saturated zone and the hydraulic head slope, the extensions of drawdown and mounding areas also depend on the local hydraulic conductivity distribution, the shape of the pit lake, its depth and hydraulic connection to any other surface water bodies [7,27,28]. Although the evaluation of each potential effect of a gravel pit lake on groundwater is not the subject of this paper, they can be accurately implemented in a numerical model.…”

“…Although the evaluation of each potential effect of a gravel pit lake on groundwater is not the subject of this paper, they can be accurately implemented in a numerical model. Jost et al (2023) [27] studied the influences of geometrical, hydrodynamical and meteorological factors on the groundwater level and water balances. The potential errors by ignoring these parameters have to be considered during the result analysis of an individual project.…”

A hydrogeological acrostic: in honour of Ghislain de Marsily

“…Malard et al [2023] present a flow animation module (FAM) designed to increase the understanding of dynamic hydrogeological processes within a web-based modelling tool called Visual KARSYS. Jost et al [2023] present their investigations relative to the link between gravel pit lakes and aquifers: they detail a gravel pit lake module developed for the CaWaQS modelling platform, which they test against the LAK package of Modflow.…”