GIS Mapping—Campus Style January 9, 2010Posted by Bahadir Sahin in Calismalar (Studies), English.
Tags: GIS mapping, GIS system, handheld GPS
When Craig Moore switched from the academic side of Virginia Tech in October 2004 to become an engineer for site development in the campus’ Facilities Department, he inherited a GIS that was not easily updated, and maintaining it was a problem. As a result, “it trailed off to nothing,” he said.
At that time the system focused on the bare essentials of collecting information on the school’s primary utilitieswater lines, electric lines, gas, steam and communications linesbut even after data was collected and stored, Moore said, “when you went back six months later and looked at the information, you didn’t know which data was accurate.”
Moore quickly realized the problem was caused by a lack of proper procedures to maintain the system. There were no procedures in place to collect data, much less a way to update it with new information and improve the accuracy of that information.
Along the way a decision was made to resurrect the sleeping GIS system, put it through a stringent muscle-building update program, and beef up its capabilities to handle everything from tracking trash cans to the number and location of parking spaces, from emergency telephone locations to incomplete construction projects, and from sidewalk damage to mapping problematic erosion areas, among other jobs.
In January 2008, Jason Shelton was brought on board as Virginia Tech GIS manager to corral and contain the data that was scattered throughout the different departments across the 2,500-acre campus into one central depository.
His group was charged with creating a centralized geodatabase to store all exterior information, get it as accurate as possible, and document the data, no matter if it was derived from aerial surveys, data collected with a handheld GPS or any other data that would let him know, “just where our infrastructure stands.”
The biggest challenge he faced initially was figuring out what information was the most accurate. “There was so much,” he commented, “so many duplicate copies of everything that we finally had to step back and look at the source data that we believed was the most accurate representation of a certain time period, use that as a foundation, and start bringing in newer projects as they came along.”
Craig Moore added, “We didn’t want to just discard that information, but to find a way to track how valuable and accurate that information was.” Jason’s group ended up developing “entry specific metadata” of objects in the GIS, Moore said. This enabled the school to know how the data was collected, when it was collected and how accurate it was for each object.
“Anything outside the buildings is inventoried,” Shelton said. “We’re talking about trash cans, mail routes, utility infrastructure, planimetric features and, from the safety standpoint, we also map out the locations of emergency phones.”
One load that Shelton’s group does not have to carry, he explained, is database administration. That’s handled by a separate IT group at Virginia Tech, he said. “That gives us the opportunity to bring the two sides—academic and facilities—together to store the data and use it for our respective purposes.”
To facilitate such a complex and ongoing job, Craig Moore relied on his own experience with the Topcon GMS-2 system and the recommendations of others who also had used the GIS-specific instrument and software.
The GMS-2 is an integrated mapping and 50-channel dual-constellation satellite tracking receiver. It incorporates an integrated electronic compass, replaceable/rechargeable battery and an expandable memory card slot. The unit enables the Virginia Tech field staff to remotely record and store any information required by the school.
The two GMS-2 units that Virginia Tech purchased run FAST software from GeoAge to update all data. FAST allows Shelton to configure simple data entry forms to collect and update specific GIS information. Digital photographs can be snapped using the GMS-2 internal camera. The photographs are automatically linked to the field data and transferred to a GIS database for easy remote access.
Moore said, “One of the things about the FAST software is that it is so easy for my folks to pick up and learn. We give the unit to people who are not equipment savvy and it is so user-friendly that even people who have struggled with computers are really taken with it. It is so much easier that they were out collecting accurate and complete data in less than two hours,” he said.
Shelton described the GMS-2 units this way: “For example, if you find exterior damage to a building, the handheld unit lets you get a picture of the damage and a geo-location. When you plot it on the map, the image appears showing what the actual damage is. When other people access the data they get a picture in the report.”
“The old-fashioned way of doing this,” Moore said, “was to go out with a clipboard, notebook, a pad, a camera and a tape measure. You had to carry all that around. You pulled measurements off the building, put it in a notebook and took a picture. With the GMS-2 you have only the one unit that has a built-in notepad, camera and tape measuring device, so to speak. This cuts down on time. You can set up and essentially import everything you’ve got in your GIS database into the GMS-2.”
One area that the facilities group has focused on in the use of FAST is erosion and sediment control inspections, said Moore. “We can get the location, get a picture of the site and fill out the necessary requirements on the forms required by the state regulatory agency for storm water management,” he said.
The state agency performs site inspections, but Virginia Tech does its own as well. “We do a preliminary inspection to keep up with what the contractors are doing on any site work,” he commented. “We can head off any problems before the state agency shows up at the site.”
During these inspections Moore said his team looks for such things as the proper installation of silt fences, for instance.”Are they properly installed? Has equipment run over them and knocked them down? The GMS-2 allows us to document that, get a picture of it, plus get a geo-location to put on a map if there are future questions about what happened.”
Another thing Moore’s team looks for during these inspections are drop inlets where the drain goes into a storm drainage system, he said. He checks to see if the drain is clogged up and if has been properly maintained.
“If there has been a heavy rain there may be a lot of silt that has left the site,” Moore said. “If so, we can go out with the GMS-2 and document collecting points of the sediment that has left the construction site. We haven’t had that happen,” Moore said, “but if it did, the GMS-2 would allow us to do that rather quickly.” The units also are used for checking out sidewalk damage and for looking at areas around campus that have experienced erosion from pedestrians, from vendors, or from state vehicles that sometime have to drive on the sidewalk to inspect buildings. In addition to the two GMS-2 systems, Virginia Tech also bought one Topcon GR-3, a system that incorporates G3 tracking technology to access all available satellite signals now and in the future.
“The GR-3 is a nice unit with 72 universal channels to track satellite signals,” Moore said. “The base station becomes a rover, and when we get a permanent base station on campus (the TopNET GPS+ reference station), which is underway now, we will be part of Caron East Inc.’s RTK reference network. At that time we will have two rovers that can go out and collect survey grade information.”
Complementing the GR-3’s RTK accuracy, Shelton uses a non-high tech approach for accuracy as well. He verifies the data that goes into his geodatabase by talking to Virginia Tech staff members who have worked there for decades, Shelton said.”You spend part of the time having conversations with these folks. Another part of checking accuracy is to go out and do your own verifications. You go out and pop lids,” he said. “When things are slow, such as in winter, we go out and survey, for example, a sewer line to make sure that we are correct.”
Shelton and Moore say there is such great potential for the Topcon systems and the FAST software that it’s only a matter of deciding what you want to do with them.”It improves our site work management in terms of storm water, sediment and erosion control and we are just at the beginning stage right now. “As we move forward,” said Shelton, “we can continue to refine the process of getting what we need into the GIS.”
G. C. Skipper is an award-winning freelance writer whose work has appeared in numerous publications, including the construction, trucking, technical and travel industries.