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Illinois Department of Transportation

IDOT Process

IDOT has a three-phase project development process. A Phase I Study consists of a Preliminary Engineering and Environmental Study which provides the support for the determination of a preferred option. During this phase, proposed geometry, environmental concerns, and proposed right-of-way are identified. Subsequently, Phase II is the phase when contract plans and the land acquisition is completed followed by Phase III, construction. The Business Route 51 project is at the beginning of Phase I.  All three phases are in IDOT’s current Multi-Year Program (2022-2027).