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IDOT Measures and Targets - State of Acceptable Condition

The CRS (Condition Rating Survey) rating of 5.5 on Interstates and 5.0 on all other roads is the lowest rating at which preservation treatments remain a cost-effective option to maximize the life of our assets and keep good pavements in acceptable condition by doing the right treatments at the right time.

The IDOT Bureau of Bridges and Structures has determined that a bridge rating of 5 and above on all bridge components is an acceptable condition (fair to excellent).

Federal Performance Measures

Performance measures for the National Highway System (NHS) were established by the FHWA in 2017 to ensure consistency in how performance is reported by the states. All states are to report the percentage of NHS pavements and bridges in good and poor condition every year.         

The FHWA rules define pavement performance thresholds for classifying pavements in Good, Fair, and Poor condition, using the performance criteria shown below.

The FHWA rules define the bridge performance thresholds shown below for classifying bridge components in Good, Fair, and Poor condition, using the National Bridge Inventory (NBI) rating scale.

National Highway System Performance

IDOT collects condition data on Interstate pavements annually and on non-Interstate pavements on a two-year cycle. Bridges receive a routine visual inspection at least every two years, except for some in good condition that are inspected on a four-year cycle. Underwater inspections are performed every five years. Other inspections may be conducted following incidents that threaten bridge stability (e.g., collisions or floods), to monitor special situations, or following new construction.

The results of the most recent NHS pavement condition assessments and bridge inspections may be accessed in the files below. The files contain both the State of Acceptable Condition and Federal Performance Measure results.