page_title: Red River Floodway
section_title: Design
hierarchical_section_title: Red River Floodway / Design
caption_attribution_description: English: Red River Floodway control structure, just south of St. Norbert. Gates across the river raise to divert water into the floodway. This picture was taken by me, W. T. Shymanski, and is hereby released into the public domain. ( I thought I'd done all that when I first uploaded it...shouldn't the responses to the automatic prompts be recorded? ) --Wtshymanski 18:00, 2 February 2006 (UTC)
context_page_description: The Red River Floodway is an artificial flood control waterway in Western Canada. It is a 47 km long channel which, during flood periods, takes part of the Red River's flow around the city of Winnipeg, Manitoba to the east and discharges it back into the Red River below the dam at Lockport. It can carry floodwater at a rate of up to 140,000 cubic feet per second, expanded in the 2000s from its original channel capacity of 90,000 cubic feet per second.
  The Floodway was pejoratively nicknamed "Duff's Ditch" by opponents of its construction, after Premier Duff Roblin, whose Progressive Conservative government initiated the project, partly in response to the disastrous 1950 Red River flood. It was completed in time and under budget. Subsequent events have vindicated the plan. Since its completion in 1968, the Floodway has prevented over $40 billion in cumulative flood damage. It was designated a National Historic Site of Canada in 2000, as the floodway is an outstanding engineering achievement both in terms of function and impact.
  From south to north, the Floodway passes through the extreme southeastern part of Winnipeg and the rural municipalities of Ritchot, Springfield, East St.
context_section_description: The Floodway protection system includes more than just the channel to the east of the city, but also the dikes along the river through Winnipeg and the "Brunkild Z-dike" extending to the west from the south of the city. The Brunkild Dike was built in 1997 during the "Flood of the Century," when the volume of water exceeded the safe capacity of the Floodway and water lapped within inches of the city's dikes. Primarily as a result of the Floodway, the city suffered little flood damage. After the 1997 flood, a 2004 re-assessment of the floodway and its channel capacity indicated that 2,550 m3/s (90,000 cfs) could be passed through the floodway during a major flood, but this is considered above the design capacity as it would submerge bridges, and the decision was made to further expand the floodway.
  The Brunkild dike is the limiting factor on the volume of water that can be diverted around the city, as a result of the extremely low grades in the area. In 2003, the province announced plans to expand the Floodway, increasing its flow capacity from 1,700 m³/s (60,000 cu ft/s) to 4,000 m³/s (140,000 cu ft/s). It was decided to widen the Floodway as opposed to deepening it because of the soil and ground conditions in the area. Many underground aquifers in the area are used for drinking water for rural residents and the aquifers could potentially be contaminated if the floodway were deeper. There is also potential for pressures to increase in the aquifers, causing a "blowout" to occur, where water would flow from the aquifers in the ground to the surface and reduce the capacity of the Floodway. Officials decided widening the floodway would be the best option despite the lower hydraulic capacity that would result.
caption: Control gates at the inlet to the Floodway
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