Hillsborough County, FL... Roadway Imaging: A New Solution to an Old Problem
Submitted By TransMap Corp. (Aug 2, 2002)
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We've all seen them. Some of us might even have been right there with them. In this bustling
economy of ours, surveyors are out in force as people add on to their homes, establish new
businesses, and expand existing infrastructure to accommodate the increase in traffic.
Hunched over orange tripods, squinting through the scopes of their theodolites, these young
men and women stand on street corners, in gutters, or on front yards and take painstaking
measurements of property boundaries. And, strangely enough, they often seem to be out
when the weather is rainy and generally inhospitable.
Surveying is an age-old art, most likely dating back to ancient Egypt, when those amazingly
precise pyramids were built. It's an essential element in accurate planning and execution of
just about every form of construction, as well as in the areas of transportation, land
apportionment, and communications. Advances in surveying, including aerial photography
and satellite imaging, greatly facilitate accuracy in measurement gathering. Even with such
technological refinements, however, surveying is notoriously time-consuming and, more
often than not, prohibitively expensive.
So when Hillsborough County, Florida, decided that it was time to have an accurate
inventory of roadway infrastructure and assets, county officials were very interested in finding
a cost-effective and timely means of collecting the data and integrating it into their existing
information.
They turned to TRANSMAP Corporation, a company specializing in digital geographic
information collection and integration, for help.
Hillsborough County, FL ... A Bit of Background
Like much of the country, Hillsborough County has enjoyed tremendous growth and
expansion during the last decade. More than one million people call the county home, with
at least 600,000 living in unincorporated areas over a region spanning 1,072 square miles.
As the county has grown, officials have had difficulty keeping up with infrastructure demands
and maintaining almost 3,000 centerline miles of roadway.
Further complicating their situation was the passage of what is commonly known as GASB
34. In 1999, the Government Accounting Standards Bureau (GASB) approved new financial
reporting requirements that essentially compel local governments to account for and report
the value of their infrastructure assets, including roads, signs, bridges, and sewer facilities.
The purpose of this legislation is to establish evaluation criteria and determine the real worth
of such assets, so that the disbursement of federal funding under the 1991 Intermodal
Surface Transportation Efficiency Act (ISTEA) is accurate, efficient, and fair.
 In light of such developments, it became
apparent to Hillsborough County officials that a
comprehensive and centralized asset
management system was needed, with accurate
information that could be accessed by all county
departments. A primary goal of such a system
would be the ability to do more than simply react
to problems but to actually prevent them from
occurring. County officials would also be able to
keep better tabs on monies spent repairing,
replacing, and installing assets, as well as to
budget for such expenses in the future.
When officials examined their existing GIS, they
realized that it was far from complete and also
less than reliable, since many of the new developments had not been included on the map.
The prospect of gathering all the data they needed to flesh out the GIS—information
describing what assets the county possessed, where they were located, and even what
condition they were in-- was a daunting one, to say the least. "Simply collecting the data
would have taken an estimated 27,000 man hours," says Rob Little, Hillsborough County
Project Manager. "Not to mention all the time spent on in-house data manipulation and
database work."
Mobile Mapping Technology
Instead of relying on these traditional methods of data collection, Hillsborough County
decided to go with something a little different: TRANSMAP’s terrestrial imaging system,
which makes use of ON-SIGHTTM technology to provide stereoscopic images of roadway
features. These images can then be used to create an accurate basemap of road
centerlines and precisely inventory bridges and traffic signs. In addition, TRANSMAP is able
to use the images it collects in the field to perform a conditional assessment of the assets
being inventoried, assigning each one a rating of Good, Fair, or Poor. These ratings greatly
assist officials in determining maintenance and/or replacement needs for county
infrastructure.
Using vans equipped with four digital cameras, a Global Positional System (GPS) receiver,
and an inertial navigation system, TRANSMAP drove all of Hillsborough County’s 3,000
centerline miles in both directions, taking snapshots of roadside attributes every 35 feet to
provide 360° coverage. From September, 1999, to January of 2000, two TRANSMAP vans
collected more than 600 gigabytes of photos—driving up to 10 hours a day, even in the face
of two hurricanes that, thankfully, did not materialize.
In its effort to provide Hillsborough County with accurate and complete information,
TRANSMAP partnered with two other firms: Infrastructure Management Services of Arlington
Heights, IL, which performed pavement analysis; and Cumbey & Fair, Inc. of Clearwater, FL,
which did an independent QC of TRANSMAP's roadway data and found that it was better
than sub-meter accuracy.
"This was by far our most challenging project to date," confesses Kurt Novak, TRANSMAP
president. Founded in 1994, the company has successfully mapped more than 10 counties
in Ohio alone, as well as in other states, but the difference with this project was the sheer
number of assets Hillsborough was interested in cataloging. "They wanted an inventory of 25
different roadway objects, when usually all we’re asked to collect is traffic signs or guard
rails," Novak explains.
Putting the Data to Work
Indeed, the wealth of information gathered in the four-month time span is staggering.
Inventory and condition assessment data was extracted on more than 15,000 intersections,
20,000 miles of linear assets, and 373,000 point assets such as traffic signs, manholes,
and storm drains. "We didn’t have any idea before this project what the real numbers were
like, how many miles of linear assets we had," says Little. He laughs, "We found out that
we’ve got 86,000 signs, 13,000 of which are stop signs!"
 Another challenge posed by this project was integrating all the information gathered by the
mapping vans into the county’s existing GIS. TRANSMAP worked with county staff to
populate their Hansen's Roadway Module database with information gathered from the field.
Little describes the process of inputting the data into the county’s asset management
system as a slow and painstaking one. Similarly, the task of matching up the county’s
preexisting basemap
with the one created
with the new data
was difficult.
Ultimately, Novak
says, they were able
to create a linear
reference system
from the old data and
use a technique
called dynamic
segmentation to
display the assets in
the GIS that were
surveyed during
TRANSMAP’s
journeys over county
roadways.
Hillsborough County
officials are already realizing benefits from the successful completion of the TRANSMAP
inventory project. Bernardo Garcia, the county’s public works director, explains, "Now that
we know where our roadway assets are, we were able to develop a preventative maintenance
plan for next year’s budget within a few days. This system will allow us to achieve a high
return on our annual capital and maintenance investments."
What’s Next?
Given the dynamic and thriving nature of Hillsborough County, it only stands to reason that
the snapshots obtained by TRANSMAP have a limited shelf-life in terms of comprehensive
accuracy. New infrastructure and developments make ongoing data collection and GIS
integration a must for the county.
One way to keep on top of these changes is to enable county personnel to make changes
to the database from the field, using mobile computers to access the archived images. As
part of its commitment to Hillsborough, TRANSMAP provides online access to images
collected during the mapping process and is currently working on software that would enable
officials to implement a county-wide intranet for the purpose of maintaining and using the
data.
Novak is understandably pleased with the success of the project, which was completed in11
months as promised and substantially under budget. Little is also satisfied: "TRANSMAP is,
in many ways, ahead of its time in developing and implementing a cost-effective method for
gathering a tremendous amount of data about our roadways in a short period of time."
About TransMap
TRANSMAP is a geographic information services company that focuses on collecting and
managing information related to property, assets and conditions using advanced satellite, inertial
navigation, and digital imaging methods to collect precise location and visual information for use
with any GIS.
We are the leading GIS and Asset Management
System service provider for state and local
governments.
TRANSMAP offers a comprehensive solution for
infrastructure inventory, management, evaluation
and legacy integration.
Contact:
TRANSMAP Corporation
1275 Kinnear Road, Suite 109
Columbus, OH 43212
Phone (614) 487-3636
FAX (614) 487-3704
e-mail: info@transmap.com
http://www.transmap.com
Copyright 1994-2002 TRANSMAP Corp.. All Rights Reserved.
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