Rivers Behaving Badly
The CBC is now reporting that the Manitoba floods declared provincial emergency
Manitoba declared a provincial state of emergency Monday afternoon as the flooding threat heightened in the southern areas of the province.
Canadian Forces members were being dispatched to Manitoba’s second-largest city, Brandon.
The province is also calling in engineers to find ways to increase capacity of a key flood-fighting mechanism, the Portage Diversion.
Water flows on the Assiniboine River are now well beyond diversion capacity and dikes from Portage la Prairie to Headingley need relief, officials said.
Normally, it is the Red River that floods the area around Winnipeg, but they have taken care of the worst of it through control projects, but this year it is the Assiniboine River in western Manitoba that won’t stay in it’s banks.
[Diversion = Spillway, Dike = Levee.]
CNN says that the Army Corps battles to keep the Mississippi out of New Orleans, but they are trying to keep a lot of other places dry all along the length of the River.
The Bonnet Carre Spillway was opened on Monday to divert some of the water from the Mississippi to the Gulf of Mexico by way of Lake Pontchartrain, but it will probably not be enough. The Morganza Spillway will probably have to be opened to divert water into the Atchafalaya River which will definitely cause flooding. It has become a matter of flooding the fewest number of people at the lowest possible cost.
A lot of the local flooding is being caused by small rivers not being able to drain into the Mississippi, and in some cases, the water level in the Mississippi reversing the flow. Another major problem is that the level is expected to remain high, even after the river crests, which will soak the levees and weaken them.
May 9, 2011 Comments Off on Rivers Behaving Badly