Name
HYDROGEOLOGICAL INDICES – A QUANTITATIVE APPROACH TO MONITORING AND CHARACTERIZING GROUNDWATER DYNAMICS IN PRAIRIE GROUNDWATER SYSTEMS
Description
Groundwater hydrographs are important sources of information on groundwater systems, and reflect the complex interaction of hydrogeological properties, climatic drivers, and anthropogenic stressors such as land use changes and water resource extraction. Interpreting the impact of these controls on groundwater systems is important for the management of groundwater resources; however, there is no consensus regarding the systematic and quantitative interpretation of groundwater level dynamics. The quantitative description of time series using indices has been widely adopted for describing streamflow hydrographs, but have not yet been broadly applied to hydrogeological applications. The objective of this study is to review typologies and indices available for the systematic and quantitative description of groundwater level time series, and to identify indices that are most effective for characterizing Prairie groundwater system dynamics. For this study, twenty groundwater hydrographs were selected from Saskatchewan’s observation well network. Indices describing hydrograph shape, structure, and distribution were assigned to the selected time series. Additional novel indices were developed to quantify non-stationarity and long-term trends in groundwater levels. A visual skill test was conducted to evaluate the ability of each index to quantify characteristic dynamic patterns reflected in Prairie observation wells. This study demonstrates a quantitative method for characterizing groundwater level dynamics, and provides guidance on the selection and calculation of indices.