Drawdown and Surge? What the hell is that? Well, we very nearly learned the hard way what it was on our river outing this weekend in Longview. We beached my dad's boat on a nice sandy beach on the south bank of the Columbia River to let the kids play in the sand. After about an hour, a massive cargo ship appeared downstream, approaching fast. It had to be cruising along at at least 20 knots and would soon be passing by. So my dad decided it would be a good idea to unbeach the boat until the ship passed.
We pushed the boat out in the nick of time, mere seconds after the boat was away, the river level dropped about 4 feet. The ship was still about half a mile downstream. All of us are simply in awe at this nearly instantaneous drop in the river level. I put my G2 in video mode and am filming this spectacle as the ship passes by. And as I pan left and downstream I see what looks like a tsunami: Where only seconds ago was a 4 foot drop in water level, was being flooded with a now 4-5 foot surge of water.
I scramble for shoes as everone else rushes for higher ground, only in the nick of time.
Only after reviewing the video do we realize just how lucky we were. At minimal we could have lost our shoes, but at the most, Cohen, who was playing at the water's edge, could have been swept away.
I have the video available in MPEG and AVI format.
As you watch the film, notice a few things:
The water level before the drawdown. Notice there are no pebbles visible on the beach. In the video you'll see a band of them, this was under 18 to 24 inches of water.
Look at how fast the water rushed in. There wasn' 't even a wave, it was just like a massive swell.
Look at the current after it passes.
It was an exhiilerating event but in retrospect a terribly dangerous one. My dad was extremely responsible for getting the boat off the beach, as it would surely have been left high and dry. I'm not certain I would have had the wits to do that.
