Statistical Analysis of Trends in the Red River Over a 45 Year Period

Chapter 1
Introduction
The Red River of the North is formed by the confluence of the Bois de Sioux
and Otter Tail Rivers in the United States. It flows northward through the Red
River Valley and forms the border between the states of Minnesota and North
Dakota before continuing into Manitoba, Canada, and finally discharging into Lake
Winnipeg (Figure 1.1). Along its path, the Red River flows through Greater Grand
Forks and Fargo, in the United States, and through Winnipeg in Canada. The
Canadian portion of the Red River is about 249 km long, while the US portion is
approximately 636 km in length. The river falls 70 m on its trip to Lake Winnipeg
where it spreads into the vast deltaic wetland known as Netley Marsh. The entire
Red River Basin encompasses 287,500 square kilometers of rich agricultural lands,
forests, wetlands, and prairies and contains numerous lakes.
Statistical evaluation of trends in water quality data over the 45-year period of
record is useful for assessing effects of the variation in precipitation in the Red River
and the impact that landscape runoff has on water quality. Changes in the Red River
water quality have a direct bearing on Lake Winnipeg into which it discharges; the
eutrophication of Lake Winnipeg is a research priority for Environment Canada and
the Manitoba Water Stewardship.
This report, which focuses on three water quality monitoring stations along
the Red River, presents results of trend analysis using parametric methods devel-
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