Hydraulic Modelling Of The Peace Athabasca Delta Under Modified And Natural Flow Conditions

Construction of the Bennett Dam in British Columbia altered natural fluctuations of downstream flows in the Peace River in Alberta, with major implications for the ecosystem of the Peace-Athabasca Delta. In later years, downstream weirs were constructed to restore the water level regime in the Delta. This report presents the results of a modelling exercise undertaken in an attempt to assess the effect of the weirs and the dam on the Delta water levels during 1985-90, at which time Lake Athabasca water levels were low and it was not clear whether the weirs were functioning properly or if the low water levels were caused by low flows coming from the upper Peace and Athabasca river basins. The methodology uses a one-dimensional hydrodynamic model, suitably modified and calibrated. The appendices include numerous plots of water levels indicating the effects of the weirs and dam on natural conditions.

Lists Northern River Basins Study technical reports by issue number, subject, and geographic area studied. Subject areas used to classify the reports are: hydrology/hydraulics, nutrients/dissolved oxygen, contaminants, food chain, drinking water, other uses, traditional knowledge, and synthesis and modelling. Ten geographic divisions are used: three each for the Athabasca and Peace Rivers, and one each of the Wapiti/Smoky rivers, Peace-Athabasca Delta, Lake Athabasca, and Rivière des Rochers/Slave River.

Report to the federal ministers of Environment and Indian & Northern Affairs, Alberta's Minister of Environmental Protection, and NWT's Minister of Renewable Resources. Summarises the main scientific findings of the Northern River Basins Study, which was established to examine the relationship between industrial, municipal, agricultural, and other development and the Peace, Athabasca, and Slave River basins. Reviews the characteristics of the northern river basins and their peoples, the organisation of the Study, and major findings in the areas of environmental overview, use of aquatic resources, traditional knowledge, flow regulation, fish distribution and habitat, nutrients, dissolved oxygen, contaminants, drinking water, ecosystem health, modelling, human health, and cumulative effects. Recommendations by the Study Board, First Nations, and scientific advisors regarding such issues as basin management, monitoring, research, public participation, and a successor organisation are then presented. Also includes a summary of opinions, suggestions, and recommendations expressed at 17 community workshops held throughout the northern river basins area.

Provides a summary of flow and lake level information for water bodies in the Peace, Athabasca, and Slave river basins to provide a hydrologic background for many of the other reports in the Northern River Basins Study series. It examines trends in river flows for both the main stems and significant tributaries; for lake levels, both natural and regulated conditions are examined. Ice processes are also discussed along with some of the environmental effects.