Major storm Sandy shows the need for accurately knowing the location of the infrastructure elements such as gas valves, manhole covers, fire hydrants, junction boxes, quickly and efficiently after the disaster. Most utilities use a paper map or a digital map to locate these facilities. There is no widespread cooperation among the utilities, cities, and emergency management agencies on effective recovery of infrastructure elements. Earlier research shows that up to 50 percent of the cost of recovery is due to destruction of infrastructure facilities that have been covered by debris and/or sand during recovery operations.
An article published in ArcNews (Spring 2012) on the geospatial mapping of infrastructure elements in the Gulf Shores area showed how students from Auburn University had mapped the infrastructure facilities (about 10,000) next to the beach area in the cities of Gulf Shores and Orange Beach and provided the GPS information to the local utilities and cities. Further research showed that even though this information is available, it will take close to 60 days to identify and mark these infrastructure facilities. Such identification will make it easy for earth-moving equipment that removes the debris to stay clear of these facilities. While fairly reliable coordinates are provided by the GPS unit, the facilities may be buried under sand or debris when a hurricane hits or could have broken and moved to a new location. Workers must search and dig to identify the desired facilities. Broken infrastructure facilities make it harder for water, power, gas, and sewage services to be provided to residences, companies, and businesses thereby delaying the economic recovery of the coastal area.
The Geospatial Research and Applications Center at Auburn University wanted to find out whether it was possible to use other technologies such as magnetic locators and RFID tags to help resolve this problem and was able to get the necessary equipment from a company. This company had created a tag that enclosed the RFID chip in a strong metallic frame that was capped with a magnet. It is possible to program the RFID chip with information fields about that specific facility, differentiating one facility from all the others in an area. GRAC and the company worked together to create a scientific experiment where three methods - GPS alone, RFID and magnetic locator alone, and GPS, RFID & magnetic locator - were used to retrieve tags buried in an open beach area in Gulf Shores, Alabama. Both accuracy of retrieval and recovery time were recorded and compared.
Students from Auburn traveled to Gulf Shores to carry out the experiment on the beach. GRAC recruited the students and provided them with GPS units, RFID readers, and magnetic locators. The team leaders buried 15 tags in a portion of the beach.
The experiment asked students to retrieve five targets using the equipment provided for each method. For the first test, teams were provided only a GPS unit with coordinates downloaded from an ArcGIS file to locate five buried targets. For the second test, participants were provided with a magnetic locator and an RFID reader to find five buried tags. For the last test, teams were given access to all technologies (a GPS unit, a magnetic locator, and an RFID reader) to find five other buried tags. All targets were hidden at a similar distance from a set starting point at the site.
A total of 51 students performed the experiment participating in 17 teams. None of them had prior experience using the technologies. They were provided a 15 minute training session before starting the experiment and were given 15 minutes to recover the targets using each method. If the team had not located all the five targets within the 15 minutes, they were told to proceed to the next test.
Using the first method, students found that using a GPS coordinate alone was a good starting point, but frequently were unable to detect the targets. Students had to dig through the sand and hope their coordinate was accurate to limit their amount of digging. Frequently, they missed locating a target, though it was very near to the spot where digging began.
With the second method, using only magnetic locator and RFID reader led students on a bit of a "wild goose chase." With no positioning information, students had to randomly search the extent of the test site to detect targets below the visible sandy surface.
When used in combination, the technologies nicely complemented each other. A GPS coordinate guided students to the correct general location. Then, the magnetic locater was used to identify the target below the surface. The RFID reader could then identify the specific target and its information without having to dig it up. It became clear that using these technologies in combination could be very beneficial in a post-disaster setting where time and accuracy of asset recovery are vital.
Each team found targets more quickly and accurately using the three technologies in combination than using either method in isolation. Within the given time frame, students located 91 percent of the targets using the combined technologies, 39 percent of the targets using RFID and magnetic locator technology alone, and only 19 percent of the targets using GPS alone. The time taken to retrieve a target was 2.51 minutes with the combined technologies, 10.47 minutes with RFID reader and magnetic locator technology alone, and 14.11 minutes with GPS alone. Students made the following statements about their experience:
“Helped the morale of the team - without the combination of technologies I would find another job.”
“The technology together is the best – market the combination as the most efficient means to find assets.”
“Combination was dynamite!”
“Hardest to use was the RFID reader and magnetic locator alone – need GPS to generally locate the tags.”
“Using only GPS doesn’t work – I could dig all day! I know I’m in the vicinity but can’t find the target.”
“If only one technology is available, get GPS.”
This experiment shows that use of a combination of technologies, such as RFID, magnetic locators, and GPS equipment is essential in identifying buried facilities quickly after major disasters. This will require utilities to include GPS coordinates and information on the facilities on a RFID chip, enclose the RFID chip in a tag that includes a magnet, and then attach these tags to the facilities. New devices that can read RFID tags, locate magnets, and retrieve GPS coordinates need to be available to the utility workers. Widespread use of such systems can lead to more efficient and faster recovery of infrastructure facilities from major storms and hurricanes.
About the Authors
Chetan S. Sankar is the COB advisory council professor of information systems at Auburn University. He is the director of the Geospatial Research and Applications Center (www.auburn.edu/grac).
Matt Donaldson is a recent MBA graduate of Auburn University and led a project team addressing disaster recovery issues on the Gulf Coast.
Yun Wu is a PhD student in the College of Business at Auburn University. Her research interests include IT business value and IT innovation adoption.