Baseline greenhouse gas emissions for the lower Churchill hydroelectric generation project in Labrador

Newfoundland and Labrador Hydro has proposed to develop the hydroelectric potential of the lower Churchill River by constructing generating facilities at Gull Island and Muskrat Falls. This paper presented the results of a study that was conducted to collect baseline data on greenhouse gas (GHG) fluxes/emissions of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) from the lower Churchill River, Smallwood reservoir, and natural lakes in the upper and lower Churchill regions. The purpose of the study was to compare GHG fluxes between the lower Churchill River, Smallwood reservoir and those of the nearby natural lakes and to compare GHG fluxes between the Smallwood reservoir and those of boreal reservoirs in northern Quebec. The paper provided a description of the site and the methodology for GHG flux measurement. The results and discussion focused on physical-chemical variables and GHG fluxes. The study results were to be used in the environmental assessment of the project. It was concluded that the lower Churchill River has higher CO2 fluxes and lower CH4 fluxes than the Smallwood reservoir and higher CO2 fluxes than natural lakes in the region. There was no significant difference in N2O fluxes between the sampled waterbodies. Both CO2 and CH4 fluxes from the lower Churchill River were comparable to other Canadian reservoirs. 12 refs., 2 tabs., 6 figs