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This amazing scene was captured by
Arthur Lovell of Oxford, UK, around 2pm on
November 4, 2010, when a large section of
overhanging sandstone rock from the cathedral-like
gorge wall fell into the plunge-pool below, creating
a massive wave. The rock is estimated at 54 ft (16.5
m) across, and the void it left can be seen in the
before and after photos to the left. Taughannock
Falls itself is 215 ft (65.5 m) and the surrounding
gorge walls extend over 100 ft higher.
Massive rock slides often occur in
the Finger Lakes region, which is characterized by
relatively soft, and easily-fractured sedimentary
rock, but capturing the moment on camera is a rare
treat. The danger of rock falls like this cannot be
understated. In August of 2005, Deborah A. Rowen,
51, of Westmont, NJ, was killed and three others
injured at Taughannock, by a rockslide the size of a
small house.
The NY State Office of Parks,
Recreation and Historic Preservation's primary
strategy to keep park visitors safe from rock falls,
both large and small, is to restrict access to areas
at risk. In the case of the 2005 death, the victims
had crossed boundaries and wandered off the trail.
The state office also sends out scalers, men and
women who scale down overhanging cliffs near trails
to inspect rock integrity and knock loose potentially
dangerous rocks.
Rock falls are the result of natural
fractures in the rock (often created by earthquakes,
geological shift, swelling, or the natural
separation between rock layers) and can be found in
virtually all rock layers in the region. Fractures
often run perpendicular to each other, forming
blocks of rock that can be potentially knocked free.
Most are structurally safe. Environmental pressure,
erosion and weather can weaken the friction holding
blocks of rock. Most frequently, rain saturating
porous stone (such as limestone, shale and
sandstone) can add the extra weight and lubrication
to let gravity pull it free. Ice is another major
cause of slides. Rain or melt-water seeps into the
fractures and freezes. As the resulting ice expands,
it pushes the two rock faces apart. Rock falls are
very frequent during times when the temperature
rises and dips around the freezing point. Other,
less frequent, causes of rock falls can be the
extreme drying of rock, which may cause it to shrink
enough to set it free. Or plant life can grow within
the fractures (such as tree roots) and pry the rocks
apart.
Mr. Lovell's story is as follows:
"I was visiting my girlfriend who is
at Cornell, we were returning to Ithaca from Buffalo
in a rental car just before 2pm on the 4th November,
and I persuaded her to stop at the falls overlook.
She is less of an outdoors type so she stayed in the
car as it was raining, but a friendly guy pulled up
in a pickup and told me about a recent landslip that
had closed or partly closed the trail in the gorge.
We walked down the parking lot away from the falls
and eventually got a view down into the gorge where
we could see a small [backhoe] parked on a pile of
muddy soil which we concluded was the slip. This
was before I had even seen the waterfall. While we
were there, I thought I heard one or two deep
booming noises, a bit like distant blasting at a
quarry, over the sound of the rain hissing through
trees. I don't recall exactly how many there were, I
didn't remark on it too much and neither did my
companion. We parted ways at the information board,
he driving off again, and I went to see the falls."
"I was taking pictures of the view
framed by trees and the stairs down from the
overlook, when a large section of the cliff on the
left at the level of the top of the falls just
dropped away, pretty much as one lump. You can see
by comparing before and after shots that it was
about 40 by 15 by 6 feet. I reacted just as it hit
the pool and took the photo with the splash. The
boom this time was huge, like close-range thunder
echoing from the cliff-sides, and I am sure I felt
the ground shake. I imagined that they would hear it
down at the state park offices. At the time I was
surprised by how small the wave was, it washed
outside the pool but did not threaten the viewing
platform down there. I set my camera to video,
thinking there was a good chance that more would
fall and I would get the whole process in one clip.
Unfortunately nothing happened except it began to
rain a bit more. About then I realized there was a
person crossing the bridge over the creek at the
bottom, heading towards the viewing platform, who
must have witnessed the fall. I did wonder if it was
safe for them to be there. I went back to the car
and told my girlfriend what had happened as she was
looking a bit nervous but also impatient, as we were
already late for an engagement. I said I would be
one more minute, went back to look and saw a small
piece of rock come down from the same general area
and hit the edge of the pool. After that I
reluctantly left the scene."
So there were at least four falls
over the 10 minutes I was there, the one I
photographed at 2:04 being the biggest (I didn't see
the first falls, I am judging by size of boom)."
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