Winnipeg, MB – On World Wetland Day, Global Nature Fund recognized Lake Winnipeg with the dubious distinction of "Threatened Lake of the Year" for 2013. The nomination put forward by Living Lakes Canada, focused on the compounding issues facing the world’s 10th largest freshwater lake.
With a watershed that spans nearly 1 million square kilometers, and drains 90 % of the prairie agricultural land in Canada, Lake Winnipeg is considered to be the eutrophic large lake in the world. Eutrophication refers to the over-abundance of nutrients in a water body, causing algal blooms that can be toxic. For Lake Winnipeg that nutrient is phosphorus, and summer measurements of chlorophyll a, an indicator of the amount of algae, have been the highest of the world’s large lakes.
However, considering these seemingly localized issues, "Lake Winnipeg is a symbol of a much larger problem", says Bob Sandford, chair of the Canadian Partnership Initiative in support of the U.N. Water for Life Decade. "It is not just Manitoba that deserves a black-eye for this distinction", he added. "Recent research demonstrates that the toxic bacteria contributing to the declining health of Lake Winnipeg, has now been detected in 246 water bodies across Canada, at levels exceeding guidelines in every province. That these problems exist right across the country is an issue of national health and environmental concern."
Lake Winnipeg lies in Canada’s vast prairie region often referred to as the World’s Breadbasket. Like Lake Erie, where algal blooms are reappearing due to agricultural fertilizers, Lake Winnipeg’s algal problems mirror the threat of increasing amounts of phosphorus being delivered by the Red and Assiniboine Rivers. In our quest to feed the world, we are fuelling Lake Winnipeg eutrophication by removing the nutrient buffering capacity of wetlands, altering natural stream courses, reducing habitat biodiversity, and concentrating manure production facilities.
These are familiar issues for Dr. David Schindler, Professor of Ecology at the University of Alberta, who is at the global forefront of the study of the eutrophication of freshwater lakes, and has been studying lakes in Canada for over 40 years. "The largest impacts on the lake have been the explosive increase in hog farming in the Red River Basin, combined with an increased frequency of flooding of the Red River." "Phosphorus inputs have almost doubled since the mid 1990s," according to studies conducted by the Lake Winnipeg Research Consortium. "There have been five so-called 1 in 100 year floods in the Red River in the past 15 years", concluded Dr. Schindler.
This international distinction has not fallen on deaf ears. "With the world watching, we as a Canadian collective have the opportunity to take action", noted Mr. Sandford. "We have known for some time that the condition of Lake Winnipeg has been deteriorating. The world has just put us on notice that it is time to do something about it."
Contact:
Alex Salki
Chair, Science Advisory Council, Lake Winnipeg Foundation Liaison, Living Lakes Canada
Phone: +1 - 204 - 275 - 67 33
E-mail:
asalki@shaw.ca
Bob Sandford
Chair, Canadian Partnership Initiative in support of the UN Water for Life Decade
Phone: +1 - 403 - 678 - 70 03
E-mail:
sandford@telusplanet.net
Background
Lake Winnipeg is the 10th largest freshwater lake in the world and is viewed as a global climate canary. It has a watershed that spans nearly 1 million square kilometres and stretches from the Rocky Mountains to Lake Superior. Its watershed drains agricultural fields, livestock farms, and has 6.7 million people living in it. Lake Winnipeg is commonly referred to as North America's sixth Great Lake, however, the average depth is a mere 11 metres. Lake Winnipeg is considered to be at greater risk from eutrophication than all of the other Great Lakes. Lake Winnipeg's watershed drains 90% of the prairie agricultural region in Canada resulting in recurrent toxic algal blooms that have spanned 10,000 square kilometers, with nutrient loading that has exceeded ecological thresholds.
The Canada-Manitoba State of Lake Winnipeg report, released in 2011 indicates serious concern over a deterioration of water quality, with particular concern arising over accelerated nutrient enrichment during the past decade. Increasing occurrence and severity of spring flooding associated with climate change has become the major threat to Lake Winnipeg. Nutrients and contaminants are transported to Lake Winnipeg at an accelerated rate from flooded landscapes via the Red River and Assiniboine River, which increase the frequency and intensity of algal blooms. Critical aquatic issues for Lake Winnipeg include: climate change, bacteria, contaminants, species at risk, eutrophication, aquatic invasive species, overfishing, sediment levels, shoreline disturbance and water control.