A trio of shore fishermen cast into the waters of Devils Lake from a spit of land. Forum Communications Co.
Kevin Bonham - Grand Forks Herald
First, a three-year study commissioned by an international organization concluded this past fall that water being transferred from Devils Lake poses a low risk to downstream fish and fisheries.
Secondly, the same group – The International Red River Board of the International Joint Commission – endorsed a plan to develop a comprehensive nutrient management strategy that will focus on reducing nutrient contributions throughout the watershed.
The new committee is the result of a meeting in 2010 of representatives from the U.S. and Canadian federal governments, the state of North Dakota and the province of Manitoba to discuss issues associated with the Devils Lake flooding situation.
Fish study
The Devils Lake-Red River Basin Fish Parasite and Pathogen Project, Qualitative Risk Assessment, indicated that three bacteria, one parasite and several lesions identified in fish from Devils Lake are not found elsewhere in the basin.
An expert panel of pathologists determined that they could be transferred downstream through a number of pathways, including an existing outlet with gravel and rock filter, by birds, bait transfer by anglers or boats moved from one location to another.
However, the panel also concluded that the parasite and bacteria in question generally are widely distributed throughout much of North America, that none are foreign species and that they could have an adverse effect on fish health only if it was already compromised for other reasons.
“For these reasons, all the experts concluded that the risk to downstream fish and fisheries from the parasites and pathogens of Devils Lake is low, and the potential for causing disease is minimal,” the IJC said in its report.
The U.S. and Canadian governments requested the study in 2005. It was conducted by the IJC’s aquatic ecosystem committee for the International Red River Board.
Devils Lake has risen by almost 32 feet and quadrupled in size since 1993, hitting a record elevation this summer of 1,454.4 feet above sea level, less than 4 feet below the point at which it would begin overflowing from the connected Stump Lake to the Sheyenne.
According to 2005 statistics, the Devils Lake sport fishery and recreational industry was valued at $56 million annually; the Red River recreational fishery in Canada was estimated at
$10 million to $15 million annually; and Lake Winnipeg’s commercial fishery, the largest in North America, had annual revenues of more than $15 million.
The state of North Dakota began transferring water downstream from Devils Lake in 2005 through an outlet to the Sheyenne River.
While it has been expanded to a capacity of as much as 250 cubic feet of water per second during the summer and fall, mechanical problems this year have resulted in average releases of about 100 cfs or less.
By summer, the state plans to build two additional outlets and a control structure, increasing the potential transfer to as much as 1,000 cfs.
Study suggestions
The IJC’s study included these recommendations:
- Adopt a precautionary approach to monitoring and preventing the transfer of invasive species and certain fish pathogens into the Hudson Bay Basin.
- Use data from the current study to assess the risk to fish in the Red River Basin from parasites and pathogens found throughout the basin, including Lake Winnipeg.
- Use innovative risk analysis methods and techniques such as computer modeling.
- Establish a program to monitor fish parasites and pathogens.
- Start a project to determine route of transfer, rate of spread, and distribution of the Asian tapeworm in the Hudson Bay Basin. The population characteristics of the tapeworm could be used as a model to study invasion pathways of foreign species into the watershed.
Nutrient strategy
The new IRRB committee that will develop a nutrient reduction strategy includes representatives from North Dakota, Minnesota, Manitoba, the Red River Basin Commission and federal agencies in both countries.
The committee will collect nutrient reduction efforts already under way and will exchange information on nutrient-control technology and practices.
Nutrients such as phosphorus and nitrogen enter lakes and rivers from fields, discharges from treatment facilities and other sources, according to Lance Yohe, RRBC executive director.
Nutrients can cause excessive growth of algae and other plants leading to problems with water clarity and dissolved oxygen levels.
Paul Aasen, Minnesota Pollution Control Agency commissioner, said that while local jurisdictions ultimately will make final decisions on nutrient reduction, the committee can help exchange information, promote consistence wherever possible and identify high-priority areas.
“In Minnesota, we have monitoring results and watershed modeling data that show where the highest percentage of nutrients are coming from to help us focus our resources on those areas first.”
“Ultimately, it will be the people living in the Red River Basin who will be responsible for reducing nutrient inputs to our rivers and lakes,” said Dennis Fewless, director of the North Dakota Department of Health’s Division of Water Quality. “The committee’s goal is to develop a strategy based on sound science and basinwide cooperation, while retaining the nutrient management efforts unique to each jurisdiction.”
“The reduction of nutrients will improve water quality and the health not only of Lake Winnipeg but of all surface waters across the international Red River watershed,” said Nicole Armstrong, director of Manitoba’s Water Science and Management Branch, Manitoba Conservation and Water Stewardship.
Kevin Bonham reports for the Grand Forks Herald.
