City Maps Services With GIS

San Francisco pinpoints crimes, collects taxes using geospatial data.

For Erich Seamon, location is everything.

Last year, as most IT organizations were cutting budgets, Seamon, geographic information systems manager for the city and county of San Francisco, was moving forward with a project to integrate the City by the Bays geographic information in a standard fashion online. The result: City employees and San Franciscans now have online access to up-to-date geographic information, and this has dramatically increased city departments ability to do everything from collecting tax revenues to responding to crimes.

"We wanted to find a way to use this information to enable us to track the land we own as well as see in real time where crimes were happening," Seamon said. "We wanted to use this information in a way that would enable police, for example, to better protect our citizenry."

The falling costs of hardware and software, coupled with the ability for GIS data to be used to provide a multitude of services, has increased the adoption of GIS technology.

This is particularly the case within government organizations. While most IT budgets remain flat, one-third of federal, state, county and local organizations will see an increase in their GIS budgets this year, according to research company Gartner Inc., in Stamford, Conn.

The city and county of San Francisco is one municipality that has invested heavily in GIS technologies and is now reaping the benefits.

San Francisco, with approximately 188,000 leased ground lots, needed a way to plan and coordinate daily business processes, such as real property analysis and emergency services. An increasing number of departments that once relied on paper-driven planning processes to accomplish this work are now using electronic geospatial data to provide city services enhanced with location-based information.

San Francisco began its GIS work in 1993, when the Department of Public Works took 250 high- resolution photographs of the city. These photos—which included parcel information, street center lines, edge-of-pavement information and aerial views—were used to form San Franciscos core base map.

GIS data was distributed every six months to city and county departments for use in spatial analysis. Although this approach provided access to GIS information, it was difficult for the city to keep its data up-to-date. In addition, each department was running its own GIS program, forcing San Franciscos Department of Telecommunications and Information Services to support redundant systems.

Three years ago, Seamon and his team decided to create an integrated GIS solution by building a federated enterprise database system to provide spatial information to 61 municipal departments. Seamon chose to deploy ESRIs ArcSDE, which facilitates management of spatial data, and ArcIMS, to provide the foundation for distributing these spatial systems and mapping services to the Internet.

The city and county of San Francisco uses IBMs DB2 Spatial Extender Version 7.0 to manage the updating, structuring and insertion of data into IBM DB2 Universal Database Enterprise Edition for Windows NT Version 7.0 and IBM DB2 Relational Connect. DB2 Relational Connect provides access to the citys databases, allowing the use of legacy GIS data. The entire installation runs on IBM Netfinity hardware running Microsoft Corp.s Windows 2000 to create a repository of geospatial data, which is shared citywide.

"The deployment of online map services has allowed us to improve our ability to manage and facilitate city business processes," Seamon said. "Weve integrated our data to provide better public safety coordination, like emergency services, disaster planning and homeland security."

To maintain a distributed approach to GIS data sharing, Seamon and his team allow ownership and control of core data to be managed and maintained by departments while being used in enterprise GIS services. The GIS implementation resides on one server behind the citys firewall for internal intranet applications and on one server outside the firewall for Internet applications.

Today, about 1,000 city employees across 61 municipal departments access geospatial data through the ArcIMS front end using any Web browser on the citys LAN. To prevent unauthorized use of department-specific data such as crime reports or aerial photographs of key city buildings (such as the Transamerica Tower), users are required to authenticate to ArcSDE, which facilitates the management of San Franciscos spatial data.

Internally, Seamon said, city departments are or will be using ArcIMS map services for everything from managing parking meter locations to crime mapping, a function that will be available in September. Using GIS systems, Seamon said, the police department will be able to determine which pockets of the city have the highest percentage of a certain crime and can then focus task groups on those areas. Police officers will also be able to access geographical data from their squad cars to respond to emergencies faster.

Enterprise GIS is also used by San Franciscos assessor and real estate staff to manage real property information. The location data enables the city to better manage the property it owns, Seamon said.

Externally, San Francisco provides limited access to its geospatial data. Still, citizens can go to San Franciscos Web site and enter their addresses to access information, for example, about when their streets will be cleaned or on their legislative representatives.

A new application called SFViewer enables users to specify an address, city property or block number to view parcel information, aerial photographs and even print maps.

Businesses can also access an online application called SF Prospector, which allows users to view, create and print maps using GIS information as well as demographic and economic data. A law office looking for new office space, for example, could use the application to map a potential building and then determine how many other law offices are in the vicinity.

"We use GIS extensively in our day-to-day operations, and its really become a key part of our mission to use the technology to better serve our community," Seamon said.

Senior Writer Anne Chen can be reached at anne_chen@