Preliminary results and experimental design for a bulk geochemical assessment of sediment from drinking water reservoirs in Halifax, Nova Scotia, Canada


The treatment of surface water from reservoirs is a necessary and expensive undertaking. As the cost of treatment is directly impacted by changes in metal concentrations, dissolved organic carbon, and other water quality parameters, watershed managers have a vested interested in obtaining information about inter-annual to centennial scale changes that predate the monitoring record for each reservoir. From a scientific perspective, the availability of long-term monitoring data for drinking water reservoirs is conducive to informing interpretation of bulk geochemical proxies from these lakes. In partnership with Halifax Water, 6 sediment cores were taken from 3 surface water reservoirs within the Halifax Regional Municipality (HRM). Preliminary data from lakebed sediment cores at Pockwock Lake and Lake Major suggest that changes in water quality occurred in response to early logging and lake level rise following the construction of a dam in each lake. The magnitude and nature of further water quality changes will be further constrained by pending C/N stable isotope data and ^210^Pb chronology. The geochemical assessment of sediment from drinking water reservoirs is a synergistic partnership between paleolimnologists and watershed managers that will continue to be explored as the project continues.

Ontario-Québec Paleolimnology Symposium
Dewey Dunnington
Geoscientist, Programmer, Educator