Characterization of lake water and ground water movement in the littoral zone of Williams Lake, a closed-basin lake in north central Minnesota

Williams Lake, Minnesota is a closed-basin lake that is a flow-through system with respect to ground water. Ground-water input represents half of the annual water input and most of the chemical input to the lake. Chemical budgets indicate that the lake is a sink for calcium, yet surficial sediments contain little calcium carbonate. Sediment pore-water samplers (peepers) were used to characterize solute fluxes at the lake-water–ground-water interface in the littoral zone and resolve the apparent disparity between the chemical budget and sediment data. Pore-water depth profiles of the stable isotopes δ18O and δ2H were non-linear where ground water seeped into the lake, with a sharp transition from lake-water values to ground-water values [...]