Information collected during the project development stage is used to determine where and how a road will be built. In many instances, the N.C. Department of Transportation studies several options, referred to as alternatives.
Several factors go into planners and designers selecting a highway location, including public input, input from environmental agencies and aerial photography mapping to obtain reliable information on the existing physical area and the environment.
Design engineers then prepare detailed plans for the roadway within the selected location. These plans define facets of the roadway project, such as the type of highway cross-section (two-lane or multi-lane), the width of right of way required and the type of intersections and interchanges, as well as bridges, culverts and other drainage features.
Plans also identify the type of construction materials to be used and estimate the quantity of each material required to build the roadway.
These technical plans later allow NCDOT to prepare contract documents and advertisements for contractors wishing to place bids on a project.