Census Transportation Planning Package Online Query System

From global climate change models to handheld personal navigation systems, geographic information systems (GIS) have revolutionized information technology, infiltrated our culture, and raised expectations for all federal agencies whose missions include data collection, analysis, and presentation, including the U.S. Census Bureau and Federal Highway Administration. MacroSys GIS specialists are delivering data visualization solutions to our customers that are enriching their research programs and expanding the horizons of data usability.

The Census Transportation Planning Package (CTPP) is a set of special tabulations from decennial census demographic surveys designed for transportation planners. It is the only Census product that summarizes data by place of work, tabulates the flow of workers between home and work, and offers summary tabulations for traffic analysis zones that have been defined by State and regional transportation agencies-data that are highly significant for planners at the Federal Highway Administration (FHWA). CTPP 2000 Part 3 data, however, were formerly only available in a proprietary format or in CSV format. The proprietary format required users to install special software to query and process data, and the CSV format required users to download and save large data files onto a local machine. In addition, the basic geographic units at which data were available varied from county to county, increasing the complexity of the datasets and making it difficult to aggregate data over regions that contained multiple basic geographic units.

Under contract to FHWA, MacroSys improved the accessibility to CTPP 2000 Part 3 data by developing a user-friendly Web-based GIS application, the CTPP Web-based Mapping and Query System (http://gis.macrosysrt.net/ctpp2000/viewer.htm). MacroSys's redesigned system enables transportation planners to access CTPP 2000 Part 3 data at any time and from anywhere, easily select areas on a map, perform data queries for the selected areas, and display queried data in thematic maps and other map-based charts.

The system takes full advantage of recent developments in Web and GIS technology to provide dynamic spatial and nonspatial data services over the Internet using ArcIMS, Java servlets, JSP, and the Google Maps API. CTPP attribute data are stored in a MySQL database, and the supporting spatial data are stored in a geodatabase. Components of the system are modular enough to allow each to be updated and modified separately.