System Performance


System Performance is a key component of the federal performance-based planning process. FHWA published the System Performance/Freight/Congestion Mitigation Air Quality (CMAQ) Performance Measures Final Rule on January 18, 2017 (effective date of February 17, 2017) to assess the performance of the Interstate and non-Interstate National Highway System (NHS), freight movement on the Interstate System, and traffic congestion and on-road mobile source emissions.

Performance Measures & Targets

The system performance measures in the table below were established as part of the System Performance/Freight/CMAQ Performance Measures Final Rule. Some measures require 2-year and 4-year targets, while other measures only require 4-year targets. All State DOTs and MPOs are required to set targets for some system performance measures, while other targets only apply to certain State DOTs and MPOs. See the table below for details.

State DOTs were required to set initial system performance targets by May 20, 2018. Targets that were required to be set jointly also had to be set by May 20, 2018. For the remaining targets, MPOs had until October 2018 (180 days from the date the State DOT set its targets) to either adopt the State DOT’s initial targets or develop its own quantifiable targets.

NCDOT established its system performance targets in May 2018, highlighted by the following:

  • Targets are based on an evaluation of trends and external and internal factors. Details are provided in NCDOT’s baseline report NCDOT Performance Based Planning: MAP-21/FAST Act Compliance, Strategy, and Target Setting
  • Target setting frequency: 2-year and/or 4-year
  • State DOTs whose geographic boundaries include any part of a nonattainment or maintenance area for ozone, carbon monoxide, or particulate matter must establish 2-year and 4-year emissions targets for each of these applicable criteria pollutants and precursors
  • State DOTs and MPOs in urbanized areas of more than 1 million people (first performance period) and more than 200,000 (subsequent performance periods) that are also in nonattainment or maintenance areas for ozone, carbon monoxide or particulate matter must establish a single, unified 2-year and 4-year target for annual hours of peak hour excessive delay (PHED) per capita and percent of non-single occupant vehicle (SOV) travel
  • The first performance period is January 1, 2018 through December 31, 2021
  • States and MPOs will coordinate to establish targets


Since the Charlotte Urbanized Area (UZA) has more than one million people, NCDOT, South Carolina DOT (SCDOT), Cabarrus Rowan Metropolitan Planning Organization (CRMPO), Charlotte Regional Transportation Planning Organization (CRTPO), Rock Hill-Fort Mill Area Transportation Study (RFATS), and GCLMPO were required to coordinate to adopt collective, single, unified 2-year and 4-year targets for annual hours of peak hour excessive delay (PHED) per capita and percent of non-single occupant vehicle (SOV) travel. The agencies met twice, and joint targets were adopted by all respective agencies in May 2018.

The NCDOT System Performance targets are listed below.


1/1/2018 – 12/31/2019


1/1/2018 – 12/31/2021




System Performance

Percent of Reliable Person-Miles Traveled (Interstate) 80.0% 75.0%
Percent of Reliable Person-Miles Traveled (Non-Interstate NHS) N/A 70.0%
Truck Travel Time Reliability (TTTR) for the Interstate System 1.65 1.70
Total Emissions Reduction 21.0% 21.0%
Annual Hours of Peak Hour Excessive Delay (PHED) Per Capita on the National Highway System (NHS) N/A 34.0
Percent of Non-Single Occupancy Vehicle (SOV) Travel VOC: 0.252 kg/day

NOx: 2.360 kg/day

VOC: 0.504 kg/day

NOx: 4.720 kg/day


No plans are required to be developed by State DOTs as a part of the System Performance/Freight/ CMAQ Performance Measures Final Rule.

MPOs that serve a population of one million or more and represent a nonattainment or maintenance area are required to develop and update a performance plan biennially to achieve air quality and congestion reduction targets. GCLMPO CMAQ Performance Plan is available here.


NCDOT documented its system performance targets in a baseline performance period report submitted to FHWA in September 2018. It reports on progress in both a 2-year, mid-performance period progress report and a 4-year, full performance period report. The 4-year targets can be adjusted in the mid-performance period progress report. Both progress toward achieving the first period performance targets and setting of new targets occurs in the full performance period report.

A new performance period begins once every four years, on the first day of the year (except emissions-related performance, which begins on the first day of October every four years).

NCDOT’s baseline performance period report can be found here. GCLMPO coordinates with NCDOT as these reports are developed and reports its system performance targets to NCDOT via resolution.

Accountability & Transparency

In progress

Additional Resources