1-1Design Standards and Policies

This chapter establishes the design standards and policies governing highway design for IDOT. All design work shall conform to the current edition of the AASHTO Policy on Geometric Design of Highways and Streets ("Green Book") as supplemented by Illinois state-specific amendments. Design exceptions require documentation per FHWA Technical Advisory T 6640.8A and approval by the State Highway Engineer.

References: AASHTO current edition, IL Standard Specifications, FHWA Technical Advisories, and applicable federal regulations (23 CFR). Contractors shall maintain current copies of all referenced standards on the project site.