Asset management coordinator Rocky Agbunag uses a Trimble ProXT GPS receiver and a Panasonic Toughbook CF18 tablet PC to collect the point location and associated data on an inlet in a St. Johns County neighborhood. A Trimble GeoBeacon, about midway up the GPS pole, enables in-the-field data processing. Photo: St. Johns County, Fla.
Construction of the NASCAR Hall of Fame in Charlotte, N.C., includes daily lane closures and road realignments. The city developed GeoCLEAR (inset) to interface with the GIS centerline database and display the most accurate and current street-related events, symbolized by type and status. Photos: City of Charlotte, N.C.
How to Build a Shared Solution
Developing an enterprisewide database from a centerline project is all about relationships, says Twyla McDermott, GIS manager and corporate strategic technology planner for Charlotte, N.C.
The city shares resources and services with the county in which it resides, Mecklenburg. Charlotte offers public safety services; Mecklenburg oversees jails. The city guides land use, planning, and transportation for the region; the county administrates tax assessments. Even a joint Web site shows a unified effort: www.charmeck.org.
Charlotte also once managed the street centerline database used for public safety response, billing, reporting, mapping, routing, geocoding, planning, and managing assets. It was moved, however, in 1999 to the county server in anticipation of Y2K (year 2000) computer problems.
When city users encountered difficulties updating the county's database, separate databases began popping up, each updated by a different department. These databases weren't connected to each other, which complicated efforts to synchronize the city's transportation work-order management system. Also, none incorporated core data such as speed limits, thoroughfare classifications, number of lanes, and divided highways.
The data needed to be consolidated. In 2003, Charlotte's Technology Management Team formed a consortium of 14 stakeholders from city and county departments and agencies to establish a shared street centerline database. The team developed a step-by-step process:
- Interview everyone with a stake in the database to find the functional, and then technical, requirements. Function should drive technical, not the other way around.
- Design a street centerline data model based on functional requirements. (The new model is based on UNETRANS, a data model designed in part by ESRI specifically for transportation needs.)
- Compile data from different departments into one centerline database.
- Delineate impedance data to enhance routing capabilities. Physical features such as medians, bridges, and overpasses are delineated from orthophotos. Nongraphic impedance data such as speed limits, divided roadways, and one-way street directions are also included.
- Convert the database. Load source centerline data into a final data model structure. Include the compiled street center-line, bridge data, intersections, and transportation asset data-related fields.
- Standardize the editing process. Document who edits the data, how it should be edited, and what kinds of updates should be included.
The city and county funded the $169,000 project through existing budgets. An additional $92,000 of city funds also paid for a centerline edit application to update the data.
Now almost four years old, the database is used by:
- CharMeck's 311 citizen call center to locate and record citizen requests that are tied to addresses.
- Charlotte Solid Waste Services for collection routing and bulky-item pickup scheduling and routing.
- Public safety agencies in Charlotte-Mecklenburg for emergency response.
- The Charlotte Area Transit System for public transit routes.
- Planners and private developers to plan for growth.
- The Charlotte DOT for overall planning, new road development, scheduling resurfacing projects, performing connectivity analyses, measuring traffic flow, and general street maintenance.
The database also led to GeoCLEAR (Geographic Information for Street Closures, Events, and Adverse Weather Response), developed by city staff. Launched last June, the visual “dashboard” interfaces with the database to show in real time where events such as parades, storms, and traffic accidents are occurring on the roadways.
Additionally, the database is one of the foundational layers for a forthcoming citywide work-order and asset-management solution.
“We're focusing on a shared data solution for everyone,” says McDermott.