System Performance assesses the performance of the Interstate and non-Interstate National Highway System (NHS) for the purpose of carrying out the National Highway Performance Program (NHPP); assesses freight movement on the Interstate System; and assesses traffic congestion and on-road mobile source emissions for the purpose of carrying out the Congestion Mitigation and Air Quality Improvement (CMAQ) Program.
A requirement of the CMAQ Performance Measures (Traffic Congestion & Total Emissions Reductions) is the development of a CMAQ Performance Plan (CPP) to be updated biennially. The CPP includes a baseline level for traffic congestion and emissions, a description of the progress made in achieving performance measure targets, and a description of projects funded through the CMAQ program & their potential impact on achieving the targets.
CMAQ Performance Plan
Final Report, 1st Performance Period - October 2018 to 2022
Baseline Performance Report, 2nd Performance Period - October 2022 to 2026
Traffic Congestion
This subpart is applicable to all urbanized areas that include National Highway System (NHS) mileage and have a population over 1 million that are, in all or part, designated as nonattainment or maintenance areas for Ozone (O3), Carbon Monoxide (CO), or Particulate Matter (PM10 and PM2.5) per National Ambient Air Quality Standards (NAAQS).
As the Memphis Urbanized Area, which covers parts of Tennessee, Mississippi, and Arkansas, including the Planning Areas of the Memphis Urban Area Metropolitan Planning Organization (MPO) and West Memphis MPO, meets the threshold set, the following performance measures applied to the Memphis, TN-MS-AR Urbanized Area:
- Annual hours of peak hour excessive delay per capita
- Percentage of non-single occupancy vehicle travel
On May 19, 2022, the Transportation Policy Board (TPB) of the Memphis Urban Area MPO approved a resolution to support the update the 4-year target (previously adopted August 20, 2020), for the Tri-State Urbanized Area, which are shown in the table below:
| Memphis, TN-MS-AR Urbanized Area | |||
|---|---|---|---|
| TRAFFIC CONGESTION PERFORMANCE MEASURES | Baseline | 2-YEAR TARGET (2024) | 4-Year Target (2026) |
| Percentage of Non-Single Occupancy Vehicle Travel | 16.8% | 16.2% | 16.2% |
| Annual Hours of Peak-Hour-Excessive Delay | 8.4h | 9.6h | 9.6h |
Additional Resources
Resolution to Support the Updated CMAQ Performance Measure Targets
Memphis MPO CMAQ Performance Measures Presentation
University of Tennessee PHED Analysis Presentation
Total Emissions Reduction
This performance measure is only applicable to areas that include any part of a nonattainment or maintenance area for Ozone (O3), Carbon Monoxide (CO), or Particulate Matter (PM10 and PM2.5) per National Ambient Air Quality Standards (NAAQS). This measure is limited to these areas to further the CMAQ’s program purpose of funding programs and projects that seek to satisfy the NAAQS.
As the Memphis MPO has a population greater than 1 million and is designated as maintenance for Ozone (O3) and attainment for Carbon Monoxide (CO), performance targets for this measure must be established. On May 19, 2022, the Transportation Policy Board (TPB) of the Memphis Urban Area MPO approved a resolution to support the update to the 4-year target (previously adopted August 20, 2020) for Tennessee portion of the Memphis MPO area, which are shown in the table below:
| Tennessee (TDOT) | Mississippi (MDOT) | |||||
|---|---|---|---|---|---|---|
| CONGESTION MITIGATION AND AIR QUALITY PERFORMANCE MEASURES | Baseline (2018-2021) | 2-Year Target (2024) | 4-Year Target (2026) | Baseline (2018-2021) | 2-Year Target (2024) | 4-Year Target (2026) |
| Total Emissions Reductions (VOC) KG/DAY | 51.440 | 33.968 | 42.072 | 0 | >/= 0 | >/= 0 |
| Total Emissions Reductions (NOX) KG/DAY | 201.137 | 32.670 | 50.671 | 0 | >/= 0 | >/= 0 |
Travel Time Reliability
State DOTs and MPOs are charged with reporting the measurement of travel time reliability on the Interstate and/or non-Interstate NHS. State DOTs are required to set 2-year and 4-year targets, while MPOs only have to set 4-year targets. For each of the below performance measures, MPOs can agree to support the State DOT target, or establish their own target specific to the MPO planning area:
- Percent of the Person-Miles Traveled on the Interstate that are reliable
- Percent of the Person Miles Traveled on the Non-Interstate National Highway System that are reliable
On February 16, 2023, the Transportation Policy Board (TPB) of the Memphis MPO approved a resolution to adopt the 4-year targets (previously adopted November 15, 2018, updated November 19, 2020). The current targets are shown in the table below:
| Tennessee (TDOT) | Mississippi (MDOT) | |||
|---|---|---|---|---|
| Travel Time Reliabililty Performance Measures | Baseline (2021) | 4-Year Target (2025) | Baseline (2021) | 4-Year Target (2025) |
| Percentage of Person Miles Traveled that are Reliable (Interstate) | 92.1% | 88.2% | 99.6% | >93% |
| Percentage of Person Miles Traveled that are Reliable (Non-Interstate NHS) | 93.4% | 89.4% | 95.0% | >85% |
Freight Movement
This differs from the Travel Time Reliability measure and it is broken down into five periods: morning peak, midday, and afternoon peak Monday – Friday, weekends and overnight for each day.
Similar to performance measures for Emissions Reduction and Travel Time Reliability, State DOTs are required to set 2-year and 4-year targets for Freight Movement, while MPOs only need to set 4-year targets. For the below performance measures, MPOs can agree to support the State DOT target, or establish their own target specific to the MPO planning area:
- Percentage of Interstate System mileage providing reliable truck travel time
On February 16, 2023, the Transportation Policy Board (TPB) of the Memphis MPO approved a resolution to adopt the 4-year targets (previously adopted November 15, 2018, updated November 19, 2020). The current targets are shown in the table below:
| Tennessee (TDOT) | Mississippi (MDOT) | |||
|---|---|---|---|---|
| Freight Movement Performance Measures | Baseline (2021) | 4-Year Target (2025) | Baseline (2021) | 4-Year Target (2025) |
| Truck Travel Time Reliability (TTTR) Index | 1.32 | 1.35 | 1.14 | <1.4 |
By agreeing to support the states’ (Mississippi and Tennessee) System Performance, Freight, and CMAQ targets, the Memphis MPO agrees to:
- Work with the states and relevant stakeholders to address areas of concern related to travel reliability, freight movement, traffic congestion, and emissions reduction within the metropolitan planning area
- Coordinate with the states and include the system performance, freight, and CMAQ targets for those measures in the long-range regional transportation plan (RTP)
- Integrate into the metropolitan transportation planning process, the system performance, freight, and CMAQ goals, objectives, performance measures and targets described in other state transportation plans and processes
- Include a description in the TIP (Transportation Improvement Program) of the anticipated effect of the TIP toward achieving system performance, freight, and CMAQ targets in the RTP, linking investment priorities in the TIP to those targets
Additional Resources
Resolution to Support Safety Performance Measures for the State of Tennessee and the State of Mississippi - as adopted 11.19.20
Resolution to Support the System Performance Measure Targets for the State of Tennessee and the State of Mississippi- as adopted 11.15.2018
Memphis MPO Performance Measures Presentation (Online Workshop 2018)
