Monday, April 11, 2016

"Geography" Happens

In my first year at university in Vancouver, my favorite course was an introduction to "physical geography." I found it fascinating to discover how rivers meander over time, as they carry silt downstream, depositing soil at turns in the river, obliterating sharp curves, eventually depositing the remaining silt at the mouth of the river, forming fertile deltas.

That's how the Vancouver delta was formed, the rich farmland at the foot of the mountains, we were told. The geography was all around us. It was amazing to see what happened over long periods of time.

Then mid-way through that school year, after our Christmas break, a landslide obliterated part of the highway between my hometown of Kelowna, BC and Vancouver, where I was now studying. In fact, I had traveled that highway just a few days before. Now that stretch of the road was impassable. (Eventually it was re-built around the slide.) Again, our geography instructor explained how a mudslide like this could happen, showing us that geographical change sometimes occurs very quickly.

I thought of this recently when reading about a spring landslide that occurred a few weeks ago not far from Ottawa. On our recent trip to Arnprior, as we were admiring the river view from a park, a stranger commented on how muddy the Ottawa River looked.








Part of it was blue - but a brownish stream ran right through the middle.








I've never seen it like that before, he told us. We assumed he was a local.

A few days later, Terry pointed to a story in the Ottawa Sun, one of our local papers.

Here's the cause of all that mud in the Ottawa River, he said. A large landslide had deposited a hillside into one of the rivers that flows into the Ottawa River, blocking part of its flow. Ten hectares of land had been washed right into the river, causing local flooding.

The mud we had seen in the Ottawa River had originated  in that washed-out hillside. Again, in a brief moment, geography had changed!

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