Northern Subarea Study/Corridor Analysis

Base map of the study area.

The Northern Subarea Study/GA 400 Corridor Analysis (NSAS) was commissioned by the Georgia Regional Transportation Authority (GRTA) to evaluate transportation, land use, and environmental issues in a 1,080-square-mile area of northern metropolitan Atlanta. The study evaluated alternative combinations of transportation and land use strategies to best meet the mobility needs of the area, included a cost/benefit analysis of infrastructure investments, land use and development policies, and the air and water quality ramifications of continued growth. The results of the study identified three alternative transportation futures for the six-county northern subarea, each with advantages and disadvantages in providing transportation capacity for the area’s current and future population. Study findings also served as input to the Atlanta Regional Commission, the Georgia Department of Transportation, and each city and county in the study area.

PBS&J was a major subcon­sultant on the team selected to conduct the NSAS, with responsibilities for study area evaluation, issues identification, public involvement, travel demand forecasting, air quality analysis, project identification and selection, concept engineering, cost estimating, environmental analysis, and geographic information systems (GIS) development. As part of the GIS development efforts for the project, PBS&J assisted the prime consultant with a GIS data needs assessment and production of the GIS data development and analysis plan document. PBS&J designed and compiled the comprehensive GIS database, coordinated GIS data dissemination, performed travel demand model TAZ modifications, conducted existing and future land use analysis and mapping, and mapped data for alternative land use and transportation scenarios.