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The
Dynamic Landscape of the Outer Banks - continued -
Devastated
Dunes:
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| A
month after Isabel (Sept. 2003) sections of Hwy.
12 were still limited to one lane as crews worked
feverishly to remove sand from the pavement and
use it to rebuild the flattened dunes. |
Hurricanes,
tropical storms and "Nor'easters" can exact a terrible
toll on the landscape of the Outer Banks. The first trips
which collected images for this web site came as soon
as non-residents were allowed back onto the Outer Banks
after Hurricane Isabel. But before that could happen,
much of the damage
along NC Hwy. 12 had to be cleared first. Immediately
after the storm, as NC DOT road crews began this daunting
task, NOAA undertook aerial surveys of the entire Outer
Banks, providing high resolution photographs of what the
storm had done to the dunes and buildings. These photos
show entire stretches of beach dunes spread across the
landscape like melted butter.
 
Stretches of the highway looked
like desert, lined by dunes
completely devoid of vegetation. The DOT worked for
weeks to reconstruct
the protective dunes from immeasurable tons of sand
which had covered the highway and smothered vegetation.
Piles of sand were heaped
on the sound side of the highway by bulldozers and
front-end loaders, waiting to be transferred back across
the road to the beach. The pavement
was broken and washed away in many places, and had
to be repaired.
The two photos below provide a panoramic
ground-level view and an aerial
view comparing the same area, about two miles south
of Oregon Inlet, where some of the largest beach dunes
on Pea Island had stood. It is easy to see the size of
these dunes by comparing them to the truck in the left
photo. This image shows how the dunes were sliced through,
leaving isolated sections intact. The labels on the photos
provide reference points to show how the panoramic ground-level
photo, taken one month after Isabel, relates to the NOAA
aerial photo at the very same location taken just days
after Isabel.
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In
both photos, North is to the left. Each photo is
2000 pixels wide.
You will most likely need to scroll to see the full
width. |
 The
aerial photo above shows how the sand was washed across
the highway, fanning out like cake batter in a pan. This
can also be seen in the ground-level
photo at left. Some of the sand had already been cleared
from the pavement on the left side of this aerial photo.
The tiny yellow dots on the far right side of the aerial
photo are NC DOT vehicles (trucks, bulldozers and front-end
loaders) working their way south, moving the sand and
rebuilding the dunes.
When Manmade Structures Get In The Way:
When nature decides to rearrange
the landscape on the Outer Banks, it doesn't care whether
man has put roads, telephone poles, utility pipes or homes
and businesses in the way. None of it can withstand a
head-on confrontation with the unimaginable forces of
wind and water that can come to bear in hurricanes, nor'easters
and tropical storms. Hatteras Village took a vicious hit
from Hurricane Isabel when it cut the town off from the
rest of Hatteras Island with Isabel Inlet.
The USGS oblique aerial photo above was taken in September
of 1999, four years before Hurricane Isabel. It shows
the buildings
along the beach front of Hatteras Village (viewed
looking westward) near the north end of the village, and
just south of where the inlet was later created by Hurricane
Isabel. Red circles with yellow X's were added to mark
buildings that were later swept away in that hurricane.
Note the small white-roofed buildings lined up in four
neat rows side by side in the lower center of the photo.
This next oblique aerial photo (above)
from the USGS was taken just four days after
Hurricane Isabel at the same location. It shows what
can happen to buildings when they get hit by the same
forces that slashed Isabel Inlet and washed away the beach
dunes in many places along the Outer Banks during that
same vicious hurricane. The red circles with yellow X's
now mark missing buildings that existed prior to the storm.
The small pinkish dots mark buildings that were picked
up and moved by the storm. Most of them came from the
four rows of small buildings mentioned above. The yellow
arrow in both photos shows how the "L-shaped" motel was
broken in half and folded westward, coming to rest on
top of the swimming pool. Sand piled several feet deep
covers everything. The pools were filled and covered by
sand, or demolished altogether.
Many more "before and after" photos
like these can be seen at the USGS
Hurricane and Extreme Storm Impact Studies web site.
The photos cover much of the Outer Banks, providing direct
comparison of the landscape as it existed before and after
Isabel's fury. You can also go directly to the page
for Hurricane Isabel or directly to the page
for Hatteras Island during Isabel where the above
aerial photos were found.
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Stumps
In The Surf:
Here is an unusual sight - a tree stump in the ocean surf.
No, it didn't wash up on the shore from a storm. It actually
used to grow here, tree and all. But the forest it used
to grow in is now sandy beach. Quite a few of these stumps
are found north of Corolla, along the beach on the way
to Carova, preserved in place by the salt water. In the
past, great maritime forests grew here because of the
natural cycle of sand movement.
It's a long term cycle which century
after century, millennium after millennium, steadily marches
these barrier islands westward. Wind continually pushes
the beach sand westward, adding sand to the dunes. Then
storms and waves wash the dunes onto the sound side of
these barrier islands. This additional soil builds up
where brackish water and some protection from the wind
and salt spray makes growing conditions more tolerable
for a greater diversity of plant life.
Eventually the dunes and beach are
pushed back into the forest. The harsher conditions near
the beach kills the trees on the eastern edge as the dunes
and beach march ever westward. Over time the land where
the forest used to stand now meets the tides as beachfront,
and the stumps that were covered in sand are now covered
at high tide by salt water.
 This
relentless westward migration of the ocean has been going
on for hundreds of thousands of years. This scenario is
greatly affected too by the cycle of ice ages, which cause
the sea level to rise and fall dramatically over thousands
of years. Land that was shallow ocean becomes dry land,
plants move in, only to become inundated with ocean again
as the sea level changes. It's all a part of the dynamic
nature of these wondrous Outer Banks of North Carolina.
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