ZIFFPAGE TITLEBuilding a Better Rat

By John McCormick  |  Posted 2005-07-08 Print this article Print

Ross Furbert had to find a way to rid an island paradise of rodents. At stake: the tourist dollars that kept Bermuda's economy afloat.


Building a Better Rat Trap

The Bermuda health department thought a mapping system could help in a range of tasks, such as preparing disaster plans and responses and tracking health inspections—including rat checks. It decided to build its own applications for a geographic information system and in 2000 called in Scientific Technologies Corp. of Tucson, Ariz., a 100-person firm that specializes in mapping systems and services. The result was the Bermuda Environmental Health Database System.

BEHDS is a Web-based system. Its main components are an Oracle 8 database that holds public health records, an ArcIMS GIS packaged from ESRI for building maps, and a Web site built using the HTML markup language and Sun Microsystems' Java programming language. The system took $500,000 and about two years to build, test and deploy.

Systems development was mostly uneventful, but there were some challenges. Users, many of whom weren't computer literate, had to be trained; the system needed to be designed to talk to other government systems; and some early hiccups in the software's development had to be overcome.

"There were some bumps along the road," says David Atwood, systems planning manager in Bermuda's Information Technology Office and the government's geographic information system committee chairman. But, he says, the effort has been "successful."

The health department's effort spun out of the government's earlier deployment of geographic information systems in other departments, including Works & Engineering, which is responsible for public works and keeps all the island's addresses; Planning, which oversees new housing construction; and Land Valuation, which sets property taxes.

Those earlier efforts led to a digitized map of the island and establishment of some mapping system standards, such as the use of ESRI mapping tools. Today, not only does the map system includes all topographical information, such as elevations, coastlines and cliffs, but also buildings, utilities and transportation systems.

The BEHDS system springs into action as soon as a citizen who has spotted a rat calls in a sighting. The staffer answering the phone will enter the caller's name and address into the system. If the rat-spotter has called before, the history of the call will pop up on the screen. If it's a new caller, the system, which is tied to the Works & Engineering master address database, will check the name and address before it's stored in the system.

"Instead of cleaning problematic data, we avoid the entry of problematic data" such as a bad addresses, says Reno Fiedler, who, as director of the international services division at Scientific Technologies, worked on the health department's geographic information systems deployment.

Each day, the previous day's calls are grouped and sorted by the country's 80 postal codes. Each of the island's five health inspectors is responsible for about 15 of these sections, and the calls are bunched to coincide with his coverage area.

Inspectors get their work orders and two sets of maps from the system. One includes directions to their assignments. The other set shows maps of the buildings or areas they're assigned to inspect. The health officials use this second set of maps to take notes—marking where they have seen rodent trails, burrows or garbage piles, or where they have placed a trap. The department plans to test PDAs this summer.

The inspectors then carry those pieces of paper with them and, upon returning to the office, key the information about the visits into the mapping system. Each complaint, service call and bait placement is entered.

Supervisors who call up a map of the island will see dots on lots and buildings where health officials have worked. If supervisors click on the dot over a building, for example, another screen comes up showing the outline of the premises, with additional dots representing trap placements or other information.

Tracking the Critters

The most powerful aspect of any geographic information system is the ability to spot patterns—such as plotting all rodent complaints on a map to find out where there might be clusters of rats, and then looking at the surrounding area to see if a garbage dump or sewer is attracting the rats.

This is the health department's strategic weapon against the rats. By looking at maps over a period of weeks or months, health officials can follow the migrations of rat populations as they seek out new food sources. As Kendall and others watch the dots that represent complaints move across their maps, they can track rodent groups as they scamper from one neighborhood to the next and predict where they might show up next.

For instance, after the rodents have eaten all the garbage in one neighborhood, they quickly look for a new place to settle—usually finding recently dumped piles of garbage or uninhabited sewers. By carefully plotting new complaints on a map, seeing which direction the rodents are moving, and checking out, say, what sewers may be in the path, inspectors can go on the offensive. They can, for instance, bait the sewers before the rats move in.

"You can see amazing movement of patterns," Kendall says. "It's a really interesting thing to do."

Getting to the point where health officials could instantly call up a map based on time or space took a little effort.

One early priority: The health department and its vendor partner, Scientific Technologies, had to make sure the health system could share data with systems used by other government agencies.

For example, Fiedler says, some health inspectors also examine the plumbing of new buildings to see if the piping system is up to code. To get their building assignments and make their reports, the health department wanted to integrate BEHDS with the planning department's inspection tracking system, which ran on an SQL Server database.

Fiedler says Scientific Technologies and the health department worked with other Bermuda agencies to come up with a data exchange system. They knew that if they conformed to the same data messaging standard, it would facilitate communications between the departments' information systems. The agencies agreed to use the popular Simple Object Access Protocol (SOAP) messaging standard. When you agree to comply with this protocol, you write programs in the eXtensible Markup Language format, which puts a tag on a piece of data that allows SOAP to easily pull data from a repository and pass it to different Web-based systems.

The team also had to adjust the system to ensure that maps and data could be delivered to the staff's Web browsers in an instant. For instance, after the system was running, it started to slow down. The group found that the database's indexes needed to be tweaked.

In a database, you have tables, which hold pieces of information such as a name or a number, and views, which combine names and numbers from different tables when reports are requested. The system uses indexes to find what it's looking for. The more detailed the index, the more efficient the database becomes. However, the health department logged more data and map points than the team expected, and the indexes, as written, were too generic—which forced the system to search through several tables to find the exact information it needed. The team went back in and rewrote the indexes and view structure to better catalog the information in the system.

But Fiedler says all those problems are in the past.

In addition to better managing health issues, the department uses the system to better manage its staff.

By being able to focus inspectors right at the problem, Kendall says, and by organizing the day's list of inspections by postal codes, the team is able to get more done in a day—perhaps, he says, as many as three more jobs in a day.

"I just can't image us doing the amount of work we do without it," says Furbert, the rodent control foreman. "It has definitely enhanced our whole operation."


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