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GIS and Sandy City, UT: More than Just Maps

When law enforcement personnel think of geographical information systems (GIS), they usually think of maps. But maps are just one of the many varied layers that can be generated by current software. On the topic of traditional maps, the GIS administrator for Sandy City, UT, Ray Montgomery, said, “They’re snapshots. A printed map is always out of date. That’s what’s so bad about maps.”

But nobody has to worry about out-of-date maps in Sandy City. The employees there are currently using ArcGIS software developed by Environmental Systems Research Institute (ESRI). ESRI holds about 40% of the market share for GIS software in the United States, a dominant position in the field, and it has an especially strong presence in Utah. Several years ago, the state of Utah required all of its agencies to adopt ESRI as their preferred GIS vendor. This decree eventually trickled down to the county and local levels, with many local municipalities making the transition to ESRI.

Today, instead of making a single city map, the collective departments of Sandy City government, including the police and fire departments, have access to more than 250 layers of data that can be queried and massaged into countless maps, tables, charts and other forms of data presentations called “models.” Every section from the administration to economic development to the public works and the police department enters and maintains its own set of information within the GIS system. With 80% of all governmental data containing a geographic component, GIS should not be viewed as a stand-alone product but rather as a foundation through which most municipal data is connected.

Generating up-to-date maps may have been the traditional appeal of GIS for law enforcement and public safety, and this basic feature is still highly valued today, but this is only one capability of modern GIS software. Law enforcement, in fact, is only one of the many branches of government that GIS serves (public utilities and economic development often have the most personnel dedicated to GIS). Because so many different governmental entities use GIS and add data to it, it becomes a more powerful tool for public safety than if it were deployed by a single department. Because GIS holds so many applications in so many different arenas, its uses are not immediately apparent, even to the administrators of the systems.

“That’s one of the beauties of GIS. There are so many possible things [that] could be done that you can’t predict ahead of time. If you’ve got a word processing application, you can make letters or charts or graphs and predict the sort of output you’re going to get. With GIS and a little creative thinking, we can bring together different layers [of data] that you wouldn’t think of combining and come up with some really interesting analysis.”

GIS: Out of Necessity

As late as the 1960s, Sandy City was only a square mile in size. Explosive land development and population increases in the 1970s put a strain on government resources and uncovered a need for improved city services. Early 9-1-1 address databases and computer-assisted dispatch (CAD) services were deployed in the 1980s, but these would face major hurdles in the new century due to data-entry problems.

Early database systems were frequently inaccurate and required constant human maintenance and attention. “Every time the city annexed something, we had to manually go in and chop up the records for each street and match them with the new city,” Montgomery said. “It was very intensive on the labor side.” A fast-growing database plagued with data entry errors and a challenging user interface caused the address match rate for 9-1-1 calls in the growing city to drop below 75%. The problem called for a database administrator and a streamlined GIS system.

Twenty years ago, GIS didn’t look like it does today. Without the benefit of fast computer processors and powerful video cards, the output from early GIS systems was rather lackluster. And while the data might have thrilled an operator, the lack of visual stimulus was a limiting factor in gathering users. Montgomery remembers the early systems being “very heavy command line driven. There were some graphics to it…but very awkward to use compared to now.”

Sandy City’s current ArcGIS software allows each city department to manage its own data layers. As changes are made in a particular area, such as a new housing development, all the personnel connected through GIS, including the area’s 9-1-1 dispatch center, the Valley Emergency Communication Center (VECC), can view the latest data. Since the conversion to the ArcGIS software around 2003, the address match rate has increased to 98.5%, on par or slightly above when compared to similar communities.

GIS Applications

The true value of GIS is in its ability to access different types of data from different sources and present that data in different ways. For example, an officer who regularly pulls GIS reports in an ongoing investigating of criminal activity might find that the data he is accessing today has recently gotten “richer” due to the addition of building permits and utilities records by clerks on the previous Friday.

Taken individually, this information might not aid the officer’s inquiry, but when taken together, processed through GIS software and graphically presented, the value from the added data can be profound. Before GIS, additional data might have aided a criminal investigation, but the ability to effectively gather and process the information was typically beyond an officer’s ability (and time). Even if the information could have been assembled, understanding the stacks of data without GIS would have quickly caused “information overload.” GIS cannot only bring order to chaos, but it can help show connections between unlikely items. Many applications for government-gathered data and GIS are possible if not immediately apparent.

For example, water usage and methamphetamine production. In areas known for drug trafficking, public safety personnel could create a map comparing water usage between neighboring properties. Properties with comparable numbers of occupants, in the same physical area would likely use similar amounts of water. If one house’s usage were clearly disproportionate, it may raise a red flag. While this application has not been specifically credited to Sandy City Police, it has been used by other law enforcement agencies. Sandy City has used similar analysis to contact specific households with comparatively high water usage in an effort to reduce waste and conserve resources.

For accident patterns, with the assistance of GIS, officers can quickly identify what kind of vehicle accidents are occurring most frequently and begin to identify the cause. Is the problem because of enforcement, or is it the design of the intersection?

GIS helps with fire prevention and prediction. In mountainous terrain, GIS models provide helpful insight into the possible direction and speed of fire. Incorporating topographical and weather information of a fire’s likely course can be conveyed to first responders assisting them with information not easily accessed from the ground or the air.

Safe Routes

Several schools in Sandy City have requested maps displaying the safest walking routes for children from school to their homes. Taking into consideration traffic, congestion, and industrial sites, direct paths away from the most dangerous factors provide the safest routes. Sexual offenders and predators could also be identified for parents and administrators, as well as “safe houses” for students.

Numerous states already use publicly accessible GIS data in the forms of interactive maps to show the home and work locations of sexual offenders. See the Indiana Sheriffs’ Sex and Violent Offender Registry for a good example of this at www.insor.org. M

any sexual and narcotic-related offenses have stiffer penalties when committed within a certain distance of a school or church. Without GIS, it is difficult to determine if an offense occurred within a given distance from a school. With GIS, it is a simple matter to display a location and create a circle with a 1,000-foot radius from the crime scene to schools and churches.

Anecdotal evidence is always available from personnel about how long it takes to go from point A to B, from the station to a given location. But GIS removes the anecdote in favor of fact. Using posted speed limits and known distance for surface streets, it is possible to accurately predict response times—and not only for a given location but for ALL locations. This type of modeling is especially helpful when determining where to build or how to staff additional substations or offices.

GIS can play a role in investigations with suspect time models. “Could a suspect have walked from point A to B in a given amount of time?” is often asked rhetorically in court. With GIS, it is easy to plot both the line of sight distance between two points and the measured distance via roadways or around buildings to determine an exact distance and, therefore, a predictive model as to the plausibility of potential suspect paths to and from a crime scene.

Pin Mapping

Pin mapping is the digital version of the classic police map, mounted on a wall in a smoky room with colored push pins indicating criminal activity or last know locations. GIS software allows the pins to be connected with a click to additional data about the location, crime, offenders, victims and much more.

Nicole Varela, crime analyst for the Sandy City Police, described the hotspot maps she generates for detectives and agency administrators using GIS and crime statistics. “The finished map will have shades of red. Areas that don’t have very much crime will be light red, while the areas that have more density [an increased number of the particular crime] will be really dark red.” The value of the presented visual data is unmistakable despite that it is a rather simple process. Varela said, “I pull in all the calls for service and [the GIS] will generate a hotspot based on higher density of calls. It clearly shows where we need to focus our resources.”

Tactical deployments usually access aerial maps before a mission or warrant service, but other data such as utility shutoffs, owner and property history can be just as valuable when hostages are involved or suspects barricade themselves.

“If 9-1-1 [dispatchers] get a notice of an event, a gas leak perhaps, they can use the GIS to create a listing of telephone numbers of people within a certain radius. The GIS is used then as a query tool to create a contact list. The people making the calls aren’t seeing the GIS, they’re just going down the list and making the call,” Montgomery said.

Sandy City patrol officers and detectives take advantage of the constantly updated GIS information. When officers log into the system through their mobile data units in their patrol vehicles or from desktops in their offices, they see the most current data.

Frequently accessed reports and maps can be linked with the press of a button, allowing personnel immediate access to the latest information. For example, on a public disturbance run, a patrol officer can navigate to the address using the GIS maps and pull up additional information about the incident location, such as the name of the property owner before arriving on scene. This additional information can assist the officer on scene when attempting to establish identities of witness and suspects. This information also plays a vital role in establishing credibility for the officer. Interviewees are less likely to engage in spurious conduct when they know the officer knows their landlord’s name and contact information.

Upgrade Your GIS

GIS systems aren’t cheap. In fact, the initial setup for a city of 100,000 people can run into the tens of thousands of dollars for site licenses, user and annual maintenance fees. To make the upgrade process go more smoothly, the interested parties should be shown how the system will benefit their department. Montgomery explained his approach to gather support for the deployment of their latest GIS system.

When a single city department or division seeks an expensive new tool, it often expects to receive competition from other departments. Budgets are always tight, and every section has its pet projects. But GIS deployment for Sandy City was achieved through consensus rather than from competition. Montgomery held personal meetings with the heads and key members of city departments (including administration, police, fire, courts, public works and utilities and others) and asked what they would like to see in the new system.

Presented with a large matrix of options, the officials quickly saw that an improved system would benefit them. This process paved the way for a new GIS system by giving other departments a sense of ownership and allowing them to establish priorities for the system based on their own needs. When it came time for review, few objections were raised, and the new system was quietly approved.

With so much data being entered into the GIS system by so many different departments, a single question arises: Who controls the access? GIS systems such as ArcGIS by ESRI allow for various levels of access. Sandy City’s GIS administrators and staff oversee the entire system and provide direct support to department analysts who in turn fulfill requests from employees in their respective departments.

The ability to enter data into the system is limited to a few people in each department and is protected at all levels. The ability to run queries and browse data is provided more widely to about 100 current users. A new Web-enabled version of ArcGIS (currently being reviewed by Sandy City government) will eventually provide more employees and civilians with unprecedented access to Sandy City information. Concerns over access to this data are unwarranted. Much of the data in questions is already available in the form of traditional public access records, and sensitive law enforcement data will only accessible from internal networks and only with specific authorization.

People interested in seeing what a public GIS system can provide should visit www.crimereports.com. This free online application receives data from scores of police departments and sheriffs’ offices from across the country, including Sandy City and several other Salt Lake communities. After typing in an address, the visitor is presented with a map of the area over which digital pushpins are superimposed. Each color coded pushpin indicates a specific type of criminal activity from arson to suspicious vehicles. By default, the past two weeks of major criminal activity (Homicide and burglary among others) are displayed. Visitors can also select their own time frame and criminal activities for display.

The number of GIS software users in Sandy City, UT has increased from two in 1997 to more than 100 today. The number of map-generation requests has increased from 200 in 1989 to nearly 13,000 annually. As more personnel become aware of the power of the tools already on their desktops and mobile computers, the numbers of users and requests for access will certainly increase.

One of the first steps to facilitate the use of a new technology is to train people about its existence and availability and worth. Personnel cannot be faulted for not taking advantage of a GIS system if they haven’t been exposed to it, know how to use it, and most important, know what they have to gain by using it. While a patrol officer will certainly see the immediate benefits of an up-to-date GIS generated map, he may not realize that with a few more clicks on that same map he can also visually depict the location of every sex offender on his nightly patrol.


Published in Law and Order, May 2008

Rating : 10.0

Comments 1 Comments

Training Coordinator

Posted on : Sep 25 at 7:33 AM By BL Smith

Great article. I am forwarding it to several addtional training coordinators to pass along the information to those people who will realize what a great resource GIS is. Like we say Its not just pin maps anymore.

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