Road Management & Engineering Journal
Road Management & Engineering Journal
January 1999
TranSafety, Inc.
1-800-777-2338
(U.S. and Canada)
(360) 683-6276
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"Coordinate"-ing Traffic Signs: How Johnson County Manages 9,000 Signs Using GIS/GPS Technology

("Coordinate"-ing Traffic Signs" appeared in the Spring 1997 issue of KUTC Newsletter, a publication of the Local Technical Assistance Program (LTAP) of the University of Kansas Transportation Center. The article, written by Rufus Coleman, is reproduced here with the permission of the Kansas University Transportation Center (KUTC)).

In front of Marty Morehead's office at the Johnson County Public Works Department sits a rusted file cabinet flooded with thousands of yellow cards. Each card corresponds to an existing county sign in Johnson County and tracks the sign's condition.

"It's an ancient system, and when you are dealing with 9,000 signs, it's just impossible," said Morehead, the county's sign foreman.

But things have changed. The file cabinet has been replaced by high-tech computer equipment connected to a satellite receiver.

"Before the new system was installed, there wasn't a whole lot of organization. It was pretty chaotic," Morehead recalled. "But now we have some organization--plus a consistent history for each sign."

The new geographic information system (GIS) uses satellite information from a global positioning system (GPS) to determine the location of each sign placed in the county. Road crews in the field use laptop computers with SIGNS software by Cart‚Graph Systems to enter information on repairs as well as keep track of signs that have been damaged or removed. On a monthly basis, the new information in the laptops is downloaded into a mainframe computer at the public works office.


A portable receiver is placed next to a county
stop sign to determine its global coordinates.

According to Greg Godwin, who was largely responsible for setting up the system, one of the main reasons for keeping good, organized records concerns liability.

"I heard a statistic mentioned at a general session of this year's annual meeting of the Kansas County Highway Association that, for 20 to 30 percent of accidents, signs are cited as a contributing factor . . . and we're held liable," he said. "This new system allows us to track our signage better."

The money for the GIS system came from federal Section 402 funds administered by the Kansas Department of Transportation (KDOT). The funds were leftover from the 1995-96 fiscal year.

"Their grant was a special case. Some highway safety funds were held over because the state legislature didn't pass a mandatory helmet law," said Paul Bodner of the KDOT Bureau of Traffic Safety. "The federal penalty for not passing that legislation was that two percent of highway funds must go toward a safety project."

Which was good news for Johnson County. The $42,500 Johnson County received from KDOT paid for the global positioning system--two backpack units and a portion of the base station--and a desktop PC, the sign inventory software and one laptop computer. The GPS system allows them to determine an accurate global location for each sign and the sign inventory system helps maintain records of these positions and other data for each sign.


This receiver at the public works parking lot facilitates
communication between satellites and the county's GPS base station.

"We hired four students over the summer to collect information for each sign and label it with a bar-coded sticker with a unique number. They also set up the equipment to record the sign's GPS location," said Godwin. Working in teams of two, the students became very efficient, and they were able to cover all the county's signs in one summer.

The GPS system can determine the location of any sign accurately and quickly. "You can take the field unit (receiver) with you, turn it on, and within three minutes you can know where you are on the face of the earth, within a meter," Godwin said.

Benefits of the GIS system

By having accurate records of locations and conditions of signs, crews can save a significant amount of time and travel expenses.

"We can track all the signs that are in poor condition or that need to be replaced," Morehead said. Before, we might have had the same sign worked on by two different crews, or worse, signs that needed work that were left unattended. It saves us a lot of driving out and driving back."

Also, before the GIS system was installed, there was no good way of tracking missing signs. If a sign was reported missing, it was sometimes hard to tell where the sign actually was or even if there ever had been a sign there in the first place. Now, with the GIS system, it's easy to quickly determine that information.


The network file server stores information for the GPS system
and also houses the database that contains additional information about
the history, feature attributes, and condition of each sign.

The new system has some additional perks--like tracking vandalism.

"We're starting to see patterns in certain areas of the county where there is high vandalism," Godwin said. "Before we had to rely on someone recalling how many times a sign had been replaced."

A few things to iron out

While the county is certainly benefitting from the new GIS system, there have been a few problems. One difficulty has been acclimating work crews to the new technology.

"We're putting technology out into the field with crews that aren't used to it," Morehead said. "We're giving laptops to crews that are accustomed to replacing signs, not using computers, but people have adapted well."

Godwin said that his number one problem has been getting all the pieces of equipment to work well together. Last month they were having some problems with the mainframe freezing up while downloading information into it from the laptops. But he would enthusiastically recommend the system to other counties.

"I'd definitely recommend the system. It's turning out to be pretty good. We bought off-the-shelf software, and it's good software for sign management. We went from nothing to this, so we've made huge strides."

Next step: sign inventory

Morehead says that there are plans to also use the field computers to track sign materials inventory. "That way, we can consult and update our inventory data while we are in the field," he said.

Godwin says his next step is to integrate the department's existing GIS software--they use ESRI's ArcView--with the sign inventory system. This step is planned for the very near future.

"This will allow us to perform the graphical queries off a map, as well as map conditions in the field, visibilities, sign ratings, etc. We're doing this now, but we want tighter integration between the sign inventory software and our GIS system," Godwin said.

Despite the benefits of increased organization and more complete information, there is one thing the GIS system can't handle, said Morehead. "We still have to go out and hammer the poles into the ground."



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