Spring brings flood threat to North America
As spring warms the northern hemisphere, some people are nervously watching the river levels.
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| Canada’s rivers are expecting a large influx of water as the snow melts |
As spring brings its warming glow to the northern hemisphere, some parts are nervously watching the river levels.
The breadbasket of North America, including Manitoba, the Dakotas and Minnesota have seen the snowiest winters on record, and for many the thick snow is still lying on the ground. Some parts even reported a fifty percent increase in the autumn and winter precipitation, compared to average.
The problems are not helped by the state of the land when winter took hold. Towards the end of last year, when the land froze, the ground was already saturated. So, when the thaw comes, the ground will still be waterlogged and this means that the melting snow won’t be able to soak into it.
A late start to spring
The thaw has come late this year. The region is a key-growing area and this would normally be time to plant crops, but as the snow is still lying on the ground, this is proving impossible.
Farmers are saying that it the wettest that the fields have been at this time of year since the 1970s.
As you might expect, one of the first places to flood is usually along the banks of the rivers. One of the major rivers in the area is the Red River that, slightly unusually, flows northwards.
It originates in the US, forming the boundary between North Dakota and Minnesota, then up through Winnipeg in Canada.
A thawing river
The southern parts of the Red River thaw first, and the northwards flow of the river carries blocks of ice towards the still-frozen section of the river in the north.
This ice can then block the river, causing it to flood. Winnipeg has a huge artificial waterway which can divert excess water when necessary, but other places simply have to endure the flooding.
The region doesn’t see floods every year, but it’s certainly not unusual. Just two years ago, in 2009, thousands were forced out of their homes as the Red River Valley turned into a vast lake. This year, the warnings are equally depressing.
The US National Weather Service has warned that the Red River could even peak at a new record high.