• Introduction
• The Design
• The Implementation
• Future Development and Concerns I
• Future Development and Concerns II
• References

The Design

The Floodway runs for 29.4 miles, with depths ranging from 24' to 67'. The base width of the Floodway channel ranges from 380 to 540 feet, and the top width ranges from 700 to 1000 feet. The sides of the channel are sloped and grassed to slow the flow of water through the Floodway (Department of Resources and Development Engineering, 1963).

The Floodway is an interesting contrast in that its linear design differs so greatly from the meandering nature of the Red River itself. As an ecological feature, the straight, sharp edges of the Floodway seem unnatural, and indicate the lack of consideration of the surrounding environment in its construction. This may be attributed to several conditions, including the high cost and complexity of the excavation, expropriation of the surrounding land, engineering constraints, and the lack of concern for ecological principles during the period of the Floodway's design and construction.

Water flows up the Red River, arriving at the entrance to the Floodway just south of the Perimeter Highway, the location of the Floodway gate structure. Generally, the Floodway gates are down, at times of normal spring flow, to allow water to flow freely up the river through Winnipeg. At times of high waters, however, the gates are raised, diverting some of the Red River stream into the Floodway channel, thereby minimizing the risk of flooding in the city.

Also at this location, a 7' high inlet plug built of earth sits at 27' above the river bottom. This plug prevents the possibility of ice entering the Floodway and creating blockages that could reduce its efficiency. At times of normal summer flow, the water depth is generally only about 10'. The water has to reach depths 17' higher than this normal summer level in order for the flow to naturally pass over the plug and enter the floodway channel. At times when the river flow becomes dangerously high, the gates are raised, allowing more water to enter the channel. The water is then diverted around the City of Winnipeg, and rejoins the Red River north of the city at Lockport (Manitoba Water Resources Branch, 1997).

The Floodway was designed to handle about 60,000 cubic feet per second (cfs) of water flow, but can reach a maximum of 100,000 cfs (4). In 1997, the Floodway had a peak discharge of 74,500 cfs (2).