CDOT gives a letter grade to overall roadway condition. It is a combination of the percent of highway pavement determined to have high or moderate Drivability Life and the level of service (LOS) delivered by CDOT’s maintenance program. The Department in 2013 changed its way of evaluating pavement condition. Grades for previous years are not directly comparable.

The tunnel maintenance program tracks CDOT progress in maintaining tunnels on the State Highway System. A letter grade is given every year on maintenance activities at the Eisenhower-Johnson and Hanging Lake tunnels on I-70. Maintenance on these aging tunnels includes tunnel washing and sweeping, ventilation maintenance, snow removal, emergency response and round-the-clock television surveillance.

Highway segments and the various quality assurance data along with the overall grade, from the 2014 review of the Colorado Department of Transportation (CDOT).

Highway segments and the various quality assurance data along with the overall grade, from the 2015 review of the Colorado Department of Transportation (CDOT).

Highway segments and the various quality assurance data along with the overall grade, from the 2017 review of the Colorado Department of Transportation (CDOT).

Highway segments and the various quality assurance data along with the overall grade, from the 2016 review of the Colorado Department of Transportation (CDOT).

Highway segments and the various quality assurance data along with the overall grade, from the 2018 review of the Colorado Department of Transportation (CDOT).

Highway segments and the various quality assurance data along with the overall grade, from the 2023 review of the Colorado Department of Transportation (CDOT).