Consider developing a data warehouse early on to simplify the integration of subsequent ITS deployments and to efficiently manage operations of interdependent applications.
Chattanooga Area Regional Transportation Authority's experience in deploying transit ITS
Made Public Date


United States

A Case Study on Applying the Systems Engineering Approach: Best Practices and Lessons Learned from the Chattanooga SmartBus Project


Chattanooga, Tennessee is a city of about 170,000 people (about 500,000 in the metropolitan area) located near the Tennessee-Georgia border. The Chattanooga Area Regional Transportation Authority's (CARTA) provides transit services for the City of Chattanooga and portions of nearby counties. CARTA serves this area by providing fixed-route bus service (16 routes), curb-to-curb transit for people with disabilities (Care-A-Van), a free electric shuttle in the downtown area, an incline railway up historic Lookout Mountain, several parking garages, and management for much of the on-street parking in the downtown area. It is a moderate-sized transit organization in a moderate-sized community. In 2003, CARTA undertook an ITS project, SmartBus, which entailed introduction of many interdependent technologies across the entire range of CARTA operations:

  • Various network technologies were deployed to provide connectivity across CARTA's fixed and mobile assets
  • Technologies were deployed to help automate and modernize many field operations, such as automatic passenger counters and new bus fare boxes
  • Technologies were deployed to help automate and modernize many back office operations, such as new dispatch and revenue management systems
  • A data warehouse was developed to consolidate data collected during CARTA operations, and reporting tools were created to take advantage of this data warehouse

The deployment was challenging and susceptible to risks of failure. Effectively managing the risks, CARTA successfully implemented the SmartBus technologies over a period of 6 years, from 2003 to 2009, with most of the deployment completed. In November 2009, the Intelligent Transportation Systems Joint Program Office (ITS JPO) of the United States Department of Transportation (U.S. DOT) published an independent evaluation report documenting CARTA’s experiences in planning and implementing the SmartBus project. Presented below are lessons learned from CARTA’s experience that could be beneficial to other mid-size transit agencies’ planning for implementation of ITS program.

Lessons Learned

A data warehouse facilitates deployment and integration of various ITS technologies so that system-wide data across the agency can be processed efficiently and effectively to monitor and manage agency’s operations. The Chattanooga Area Regional Transportation Authority's (CARTA) SmartBus ITS program offers valuable guidance on the utility of a data warehouse for implementing and integrating ITS at a mid-size transit agency. Key lessons learned are identified below.

  • Consider developing a data warehouse as the first ITS application to facilitate and simplify future ITS deployments. The data warehouse was not on the initial list of systems identified for CARTA's 2003 proposal for ITS deployment support. Nevertheless, CARTA elected to deploy the data warehouse as its first ITS deployment for several compelling reasons:
    • Most, if not all, ITS deployments would be integrated with the data warehouse. Deploying the data warehouse first helped ensure that it would be operating stably before deployment of additional applications and their integration were attempted.
    • The data warehouse provided a central source for sharing data between CARTA ITS applications. Integrating the ITS applications through the data warehouse reduced the total number of interfaces that were required. It also insulated each ITS application from being impacted by changes in other ITS applications.
    • The data warehouse reduced the number of analysis and reporting tools that were required in each ITS application. Analyses could be conducted and reports could be generated through the Data Warehouse. This also reduced the number of reporting tools that the CARTA staff members were required to learn. Rather than learn a different reporting tool for each ITS application, CARTA could use the single data warehouse reporting tool to generate customized reports.
    • The data warehouse could provide immediate benefits in terms of simplifying existing CARTA reporting processes. A number of reports that CARTA had been producing manually were produced automatically by the data warehouse.
  • Use a combination of reliable hardware, software, and ITS application data to create a functional data warehouse. For planning purposes, the deployment of CARTA’s data warehouse was described in the project-specific deployment plan for ITS infrastructure projects. The initial deployment of the data warehouse was completed in 2004, which included implementation of a database application platform for the data warehouse, a data integration tool to facilitate extracting and analyzing data from CARTA applications and generating reports, and a server to host the database and data integration application. This combination of hardware and software became a functioning data warehouse as CARTA data were integrated into it, with the order of integration driven primarily by two factors:
    • The availability of a reliable data source that could be easily integrated with the data warehouse. The data supporting many of CARTA's existing processes could not be easily integrated with the data warehouse. For example, Incline Railway ticket sales were tracked via paper logs, and the timekeeping and payroll system relied on a proprietary database from which data could not be easily extracted.
    • The opportunity to simplify onerous reporting processes. A number of standard reports used by CARTA management were generated through manual or partially manual processes. The data warehouse allowed CARTA to generate reports that exactly met its needs and could be produced and distributed (via email) automatically.
  • Integrate data from agency’s various ITS applications into a data warehouse to efficiently manage operations of interdependent applications in a seamless manner. The following list describes the applications that were integrated into the CARTA data warehouse and the primary benefits associated with each type of data integration:
    • The timekeeping and payroll software. CARTA upgraded the timekeeping and payroll software soon after installing the data warehouse application, making it a natural candidate for integration with the data warehouse.
    • The fuel and fluid usage and mileage data. In 2005, CARTA deployed an electronic method for recording fuel usage, integrating the data collected into the data warehouse. The data warehouse allowed CARTA to use the reporting tools for fuel usage reports. CARTA was able to take advantage of sophisticated reporting capabilities to automatically produce monthly reports built into the data warehouse at no additional cost.
    • The maintenance management software. Data from the maintenance management system was an important addition to CARTA's data warehouse because of the importance of the maintenance process in managing CARTA's overall costs. There were a number of reports involving maintenance management data that CARTA was producing manually, either because the maintenance management system did not produce an appropriate report or the report required data not included in the maintenance management system.
    • The Ticket Vending Machine system. This system was deployed in 2005 with data warehouse integration being part of the requirements. As with the system for recording fuel and fluid usage data, using the data warehouse as the reporting tool for the TVM system eliminated the requirement for a sophisticated TVM reporting tool.
    • Fixed route and paratransit operation systems. By the time these systems were deployed, it was a standard practice at CARTA to include requirements to integrate new systems with the data warehouse during the deployment.
    • Fare box and the revenue management system. In 2008, CARTA deployed new fare boxes and a new revenue management system that managed fare box data. Data from these applications were also integrated into the CARTA data warehouse.

In general, the cost of integrating data generated by multiple ITS applications was at least partially offset by the lower costs incurred from the use of the data warehouse as the management and reporting tool for these new applications. In summary, CARTA's basic approach was to integrate new ITS data into the data warehouse concurrently with the deployment of new ITS applications contributing to greater efficiency and productivity in transit service operations.