Illinois Department of TransportationVertical Clearance. This item identifies the lowest vertical clearance under structures over the State system of highways, rounded down to the nearest inch. It is recommended to be 3 inches lower than the vertical clearance. This information is used by the traveling public, especially the trucking industry to prevent hitting these structures. This item can be obtained from https://www.gettingaroundillinois.com/ in the Obstructions and Restrictions Map. For details: Structure Information and Procedures (SIP manual) The SIP manual has been developed through a cooperative effort within the Department between the Division of Highways and the Office of Planning and Programming. IDOT and its Divisions and Offices are committed to maintaining the structure information system at a high level. This commitment is not only to satisfy NBIS requirements, but also to provide an excellent working tool in managing the bridges and other structures as they relate to the overall transportation system in Illinois. In the interest of the traveling public's safety and convenience, this commitment remains a high priority for the Department. Note : Data is updated daily.ArcGIS DynamicMapLayerhttps://hub.arcgis.com/datasets/474c97d9a5074e8fbe09268f79ee39be_15engIllinois DOT Open Data PortalPublicVertical Clearance [Illinois]Web servicesIllinoisLast Modified: 2023-11-14