https://doi.org/10.11575/PRISM/41999

Lilley, Sara (2023) Karst Hydrogeology in the Spray Mountains of Kananaskis, Alberta, Canada, University of Calgary PRISM - Theses and Dissertations, https://doi.org/10.11575/PRISM/41999

Alpine karst aquifers serve as vital sources of groundwater and play an important role in supporting local ecosystems. This study investigated the hydrogeology of the Watridge Karst Spring in the southern Canadian Rocky Mountains, an example of a snowmelt-dominated alpine karst aquifer with rapid, long-distance flow. An annual water budget suggested a catchment area of around 20 km2 and dye tracer tests revealed groundwater velocities of up to 0.14 m s−1. The aquifer has a hierarchical conduit structure with underflow-overflow dynamics, and year-round discharge is sustained by fracture flow. This dual flow network allows the aquifer to behave similarly to a surface stream over long distances, but also as a large groundwater reservoir. An innovative approach was introduced to estimate groundwater response times to snowmelt in alpine karst springs using diurnal discharge and electrical conductivity fluctuations, expanding upon previous methods using spectral analysis and cross-correlation. A continuous record of response times was obtained throughout the entire snowmelt seasons of 2020 and 2021. These showed that dilution response time steadily increased alongside decreasing hydraulic head, while celerity remained constant. Geologically analogous karst catchments in the Rocky Mountains hold the potential for storing mountain water, which warrants further studies of groundwater flow in these systems. Climate change may impact the hydrological functioning of alpine karst springs, highlighting the importance of understanding these systems for sustainable water resource management.

https://hdl.handle.net/1880/117157 PDF: https://prism.ucalgary.ca/bitstreams/f2411e16-2ffc-4b42-b598-1f35d902d754/download