This is just an incredible
improvement in the detail you’re
able to see and the overall
information you’re able to get
from looking at the imagery.”
– Tyler Grosshuesch,
GIS Analyst and Coordinator,
Adams-Columbia Electric Cooperative
binoculars in, not only can you tell what
the feature is that you’re looking at, but
every detail of it becomes very clear.
That’s the difference between 18-inch
and 6-inch,” he said. “Maybe there was
a building but you couldn’t tell what it
was, but with 6-inch you can tell that it’s
a manufacturing plant or it’s a church.”
Dan Kerntop, GIS analyst with
the City of Wausau, believes the
difference in detail and accuracy brings
a tremendous advantage to the table.
“In 2005 and 2010 we had 6-inch
photos, and this year we had 3-inch
done. That was a great improvement. It
was a little more expensive but I think
well worth the cost in the sense that
it’s a better value for an urbanized or
municipal-type area. Once people saw
it, it was like ‘Hey, we’ve got to have
this.’
“You can really pick things out –
there’s so much more detail,” continued
Kerntop, who was so impressed with the
quality of the data that he helped bring
four neighboring communities into the
program. “You’re not counting silos and
cows. You’re able to look at manholes
and sidewalks and see where streets
have been patched. You can really get a
lot of information out of that detail.”
Knowing Ayres will consistently
deliver is what keeps Kerntop involved
in the WROC program year after year.
“It’s just a familiar feeling. I know
what I’m going to get,” he said. “I know
I’m getting a good product.”
TECHNOLOGY
KEY WITH WROC
I
nnovative, high-end technology makes everything involved with the
Wisconsin Regional Orthophotography Consortium possible.
Acquiring close to 45,000 square miles of highly accurate,
primarily 6-inch resolution orthoimagery in one region – in a single,
time-sensitive flight season – had never been done. Significant
planning went into selecting the exact digital cameras and LiDAR
sensors to use. The systems needed to be capable of achieving
extremely accurate data, and the cameras needed to produce
excellent quality imagery at multiple resolutions.
“We used a combination of frame-based and pushbroom aerial
cameras that allowed us to apply the right technology to the right
job,” explained Zach Nienow, a WROC project manager at Ayres
Associates. “These sensors allowed us to collect a lot of imagery
in a short amount of time – so fewer flight lines, higher-resolution
imagery.”
Providing 15,000 square miles of LiDAR data across the state
provides its own challenges. A project of this importance requires
excellent sensors and the best chance of a successful flight.
The quantity of the data is mind-bending; conservatively over
150,000,000,000 individual vertical data points were gathered in
Wisconsin. That’s 150 billion.
“We basically used the newest LiDAR sensor technology on
the program, which allowed us to collect highly dense point clouds
very efficiently,” Nienow said, adding that server, workstation, and
software updates were required to store and process this mass
quantity of data. “We had a 100-terabyte server dedicated to WROC
to handle all the data and 15 high-end ortho and LiDAR workstations
used to process the data.”
Other key technical successes included coordination of multiple
planes and flight crews to capture data specifically when conditions
were met. Mobilization of trained surveyors across the state
provided the control needed for the required vertical and horizontal
accuracies. Major software investments were made to increase
quality and efficiency while driving down the cost of the data.
“We made significant investments in ortho processing software
leading up to WROC,” Nienow said. “That really allowed us to
enhance our processing capabilities and get the finished data to the
clients faster so they could incorporate it in their business activities.”
– Jennifer Schmidt
TRENDS
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