But so far, the trough has been wide and deep enough to allow the city's dike system to handle the rest of the river water that still flows over its natural course through the center of town.
Since last week, city workers have slowly opened massive concrete gates south of Winnipeg that normally close off the Floodway from the river. The spillover funneled into the Floodway runs north, rejoining the Red River just outside the city in a boiling torrent so loud and violent that Canadian Mounties have been called to the banks nearby to keep gawkers away.
"You don't realize how powerful this river is until you see it dump out here," Rolly Bernard, a Provincial highway worker, yelled over the roar of the spray. "It really shows you how the Floodway's doing the job."
Despite costing $63 million (Canadian) to build from 1962 until 1968 and requiring more excavation than the Canadian portion of the St. Lawrence Seaway, the Floodway's capacity is dwarfed by even larger spillways that protect New Orleans, Baton Rouge and New Madrid, Mo. from floods. Diversion channels like those and Winnipeg's are "no silver bullets" without dikes and other water control measures, said Gerald Galloway, a former U.S. Army engineer who is now dean of faculty at the Industrial College in Washington.