Monday, January 24, 2011

Horseshoe Falls separated by ice formation

Below: a summer view of Niagara's Horseshoe Falls, looking from the Canadian side.
The arrow shows one of the rock outcrops on the edge of the Falls. The amount of water which drops from directly in front of this particular outcrop pales in comparison to the flow which passes on its left and right.
[I'm not certain whether exact location of this outcrop is on Canadian or U.S. territory! It is closer to the American shore]
Click on photos to enlarge!
above: same view, Jan.24, 2011 - looking the same outcrop (directly in the center) it has become iced-over, and the usually-continuous water curtain running along the crest of the Falls has clearly been completely separated (at the top, as well as underneath, where the water plume plunges) leaving an obvious gap.
Goat Island is in the distance.
above: closer view of the water separation and the ice column beneath. For a brief period, the Horseshoe Falls have been split into two sides, there is now, for the time being, a 'Horseshoe Falls East', and 'West'!

There are four visible rock outcrops which appear along the rim of the Horseshoe Falls, which are like mini-islands, as well as some large boulders.
As the eternal erosion of the Horseshoe Falls imperceptibly continues, these outcrops are getting closer and closer to the edge of the Falls.
One of these outcrops in the last day or so has frozen over, and created an ice shelf, which can be seen is now frozen in a series of giant ice columns all the way down.
Even in the summer, this outcrop has only a small volume of river-water which flows around it at the front (the falls side); most of the water is diverted to the left and right of the outcrop, and then drops over the edge. The other outcrops receive a bit more water at their front than this one, but they're all pretty close to the edge; eventually they are going to create a permanent gap-tooth effect along the rim of the Horseshoe Falls, breaking it up into several sections, instead of the continuous shore-to shore line which we're used to.
In the photos above, the part of the Niagara River directly to the right of the outcrop is the part which carries the greatest volume of water; also, it is eroding, and it can clearly be seen as being deeper and lower than where the outcrop is. As this channel deepens, it will pull water away from those outcrops seen today, exposing them even more.
This effect can be seen in the autumn, when the hydro-generation water-diversion happens further upstream, and the river level drops significantly, revealing "new" rock outcrops which are usually underwater. Just slightly upstream from the crest of the Falls, the upper Niagara River is a very wide rapid (the Cascade Rapids), see below, parts of which are not that deep. The water-diversion creates wide swaths of newly-revealed rocks and open river-bed, some parts with barely a trickle of water running here and there, and some parts, being on an ever-so-slightly-higher elevation, become completely dry.
above: Nov.2010 - looking at the rapids -the Cascade Rapids - just above the Horseshoe Falls. The planned dropped winter water-levels have caused the entire area in the centre to be revealed: in the summer this area is mostly covered with water. Two water intake control-gates for the Beck hydro plants are seen in the upper right distance. The cranes are at work digging at the entrance to the newest Beck 3 tunnel.
 above: same view showing how small ice islands form in the shallow rapids. (click photos to enlarge!)
above: same view showing  how the entire shallow rapids area in the centre has become an ice island.
above: Mar.25, 2011 - same view of the rapids, showing little flow in the center. The long structure running across the Canadian side of the river in the distance is the control dam which regulates the flow of the river, affecting the flow of water which ultimately drops over the falls. The drop in river elevation from the control dam to the edge of the falls is about 50 feet.
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below: video of ice separation at Horseshoe Falls, taken by R.Bobak Jan.24, 2011.
video
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see also:
Niagara Falls Ice Bridge 2011
- Niagara Falls Ice Bridge  2010
- Niagara Falls Ice Bridge  2009
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 Thanks for visiting Right In Niagara!
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