Oathill Lake Conservation Society Water Monitoring

A YSI probe (ProPlus) is used to collect temperature, oxygen concentrations, conductivity/salinity and pH in depth profiles (at three fixed locations in the lake, at depths of 0.3 m, 1 m, then at 1 m intervals to the lake bottom, which ranges from about 4 m at the shallowest site to 8.5 m at the deepest part of the lake), and at 4 in-flow pipes into the lake. Samples are collected bi-weekly during the main vegetation growing season, and sporadically at other times of the year, including through-ice measurements. Secchi disc measurements are also made during open-water measurement runs. Calibration and operating procedures for the YSI probe follow the guidelines established by the CURA-H2O program formerly run by St. Mary's University, Halifax, which are, in turn, based on the procedures recommended by the manufacturer. Once or twice a year, surface and deep (~ 8 m) water samples are collected and sent to a commercial laboratory for analysis of nutrients and metals. Long-duration data loggers borrowed from Nova Scotia Adopt-A-Stream are used to track the temperature profile at the deepest part of the lake during the growing season, and, occasionally, to track conductivity over-winter in the main storm sewer feeding the lake.