Transportation Performance Management

State Highway Reliability Report - Tennessee

The information below summarizes the TPM Highway Reliability performance measures, which include two highway reliability measures and one truck travel time reliability measure. Per 23 CFR 490, State Departments of Transportation (DOTs) are required to establish 2- and 4-year targets for these measures. The targets should represent the anticipated condition/performance at the mid-point and end of the 4-year performance period. State DOTs establish targets at the beginning of each 4-year performance period, and report on progress every two years. When establishing targets, State DOTs have the flexibility to use the methodology they deem most appropriate. FHWA encourages States to review data sets and trends and consider factors that may affect targets. Performance targets should be data-driven, realistic, and attainable and should align with the performance management framework and legislative intent.

The targets and discussion of basis for targets, optional adjustment of targets, progress, and planned activities were provided by the State DOT in its most recent biennial performance report. FHWA has not edited this information. It is provided to help bring context to the State DOT's performance targets and progress. The data in the tables and graphs is from the biennial performance report or HPMS data submittal as noted below each measure summary. Any questions about the information should be directed to the State DOT.

Data reported by State DOTs was collected in the previous year, representing the condition/performance at the time of collection. Thus, in the tables and graphs below, FHWA labels data with the year representing the condition/performance, rather than the year the data was reported. The same thing is done for the targets--the year represents when the corresponding actual condition/performance data will be collected, not reported. More Information.

Significant Progress Determination
FHWA determines significant progress for these measures after the mid-point and end of each performance period. A State has met or made significant progress toward target achievement if “actual” condition/performance is equal to or better than the established two-year target or “actual” condition/performance is better than baseline performance 23 CFR 490.109(e). As provided in 23 CFR 490.107(b)(2)(ii)(A), baseline condition/performance is derived from the latest data collected through the beginning date of the performance period. FHWA will classify the assessment of progress toward the achievement of an individual 2-year or 4-year target as “progress not determined” if a State provides the extenuating circumstance information required in 23 CFR 490.109(e)(5), and FHWA accepts the information.

Most recent Significant Progress Determination for the Reliability measures

Most recent Significant Progress Determination for all applicable measures

• 

  Interstate Highway Reliable Person-Miles Traveled

• • Trend through 2021

    Desired trend: ↑

    Tennessee % of Interstate Highway Reliable Person-Miles Traveled

    
    

• Interstate Highway Reliable Person-Miles Traveled	2017	2018	2019	2020	2021
  Condition/Performance	87.7	88.1	88.2	96.0	92.1
  Target	--	--	85.3	--	83.0

• Interstate Highway Reliable Person-Miles Traveled

  • Basis for Targets
  • 2-yr Progress
  • Basis for 4-yr Target Adjustment
  • 4-yr Planned Activities
  • 4-yr Progress

  Using the Inrix tool and the NPMRDS data set to calculate the measure for 2014 – 2017, a trend line was developed which projected the 2019 value to 85.3% and the 4 year value to 83.0%. External factors were not used to modify the trend line for this period as data for this measure is not extensive and how projects impact it are not yet determinable.

  The statewide percent of person-miles traveled on Tennessee’s interstates that are reliable as of December 31, 2019 is 88.2%. TDOT’s Interstate Travel Time Reliability increased by 0.5% between January 1, 2018 and December 31, 2019. This outperforms the 2-Year target established in 2018 by 2.9% and suggests that TN will make significant progress towards achieving the 4-year target. Initial targets were set using limited data sets from the NPRMDS to calculate a trend line for the 2019 projected value. The lack of available data at the time caused TDOT to set conservative targets to mitigate potential variability in travel time reliability. This conservative target setting approach likely accounts for some of the difference between the actual and 2-year target values. Other factors that could contribute to the difference include fluctuations in raw data from INRIX including link changes and improved responses to nonrecurring congestion.

  N/A

  TDOT is expanding the Transportation Systems Management and Operations (TSMO) concept which will lead to better operations of our highways. The Traffic Operations Division is letting projects that specifically address reliability such as the I-24 Smart Corridor project. This project takes a comprehensive approach to managing the existing infrastructure and improving travel time reliability by integrating freeway and arterial roadway elements to provide drivers with accurate, real-time information to actively manage traffic. Additionally, the central software for the Traffic Management Centers is being updated which will lead to improved management activities. TDOT activities include evaluating expanding service patrols to the rural areas to help address incident management and decrease clearance time. The Traffic Operations Division is updating the TSMO Program Plan which will identify other potential projects to address reliability and performance measures in general. This plan update is focused on the major goals of the department to reduce congestion and improve reliability. Projects in this plan will not affect data during the current performance cycle.

  TDOT’s expected performance for the percent of person-miles traveled on the interstate that are reliable for calendar year 2021 is 92.1% which will outperform the baseline of 87.7% as well as the 4-year target of 83.0% and is expected to meet the requirements for a significant progress determination. While much of the increase in reliability may be due to changes in travel as a result of the COVID-19 pandemic, TDOT also completed several interstate projects which included widening, addition of truck climbing lanes, ramp improvements, and ITS additions. The largest project in TDOT history at the time, the I-440 reconstruction updated the 7.6 mile corridor to include exit only lanes and ramp improvements. This project was completed in July 2020.

• Data Sources:
  Tennessee 2018, 2020, 2022 Biennial Performance Report
  Tennessee 2018, 2019, 2020, 2021, 2022 HPMS Data Submittal

• 

  Non-Interstate National Highway System (NHS) Reliable Person-Miles Traveled

• • Trend through 2021

    Desired trend: ↑

    Tennessee % of Non-Interstate NHS reliable Person-Miles Traveled

    
    

• Non-Interstate NHS reliable Person-Miles Traveled	2017	2018	2019	2020	2021
  Condition/Performance	--	--	89.4	93.8	93.4
  Target	--	--	--	--	87.5

  Behind the data: For the first performance period only, baseline condition and 2-year targets are not required for the Non-Interstate NHS reliability measure.

• 
  

  Non-Interstate National Highway System (NHS) Reliable Person-Miles Traveled

  • Basis for Targets
  • 2-yr Progress
  • Basis for 4-yr Target Adjustment
  • 4-yr Planned Activities
  • 4-yr Progress

  Using the Inrix tool and the NPMRDS data set to calculate the measure for 2014 – 2017, a trend line was developed which projected the 2021 value to be 87.75%. External factors were not used to modify the trend line for this period as data for this measure is not extensive and how projects impact it are not yet determinable. However, it appears the number was incorrectly cited as 87.5% when reported to and approved by TDOT's Oversight Committee. 87.5% was then communicated to TDOT's MPO partners and acknowledged as the target by the Tennessee Division of FHWA. Thus, 87.5% is the target despite the 87.75% projection.

  N/A

  N/A

  N/A

  TDOT’s expected performance for the percent of person-miles traveled on the non-interstate National Highway System (NHS) that are reliable for calendar year 2021 is 93.4% which will outperform both the 4-year target of 87.5% and the baseline of 89.4%, meeting the requirements for a significant progress determination. While much of the increase in reliability may be due to changes in travel as a result of the COVID-19 pandemic, TDOT also completed several non-interstate NHS projects that provided for widening, aligning, and improving ramps and intersections.

• Data Sources:
  Tennessee 2018, 2020, 2022 Biennial Performance Report
  Tennessee 2020, 2021, 2022 HPMS Data Submittal

• 

  Interstate Highway Truck Travel Time Reliability (TTTR) Index

• • Trend through 2021

    Desired trend: ↓

     

    Tennessee Truck Travel Time Reliability Index

    
    

• Truck Travel Time Reliability Index	2017	2018	2019	2020	2021
  Condition/Performance	1.35	1.37	1.35	1.25	1.32
  Target	--	--	1.35	--	1.37

• Interstate Highway Truck Travel Time Reliability

  • Basis for Targets
  • 2-yr Progress
  • Basis for 4-yr Target Adjustment
  • 4-yr Planned Activities
  • 4-yr Progress

  Using the Inrix tool and the NPMRDS data set to calculate the measure for 2014 – 2018, a trend line was developed which projected the 2019 value to 1.35 and the 4 year value to 1.33. External factors were not used to modify the trend line for this period as data for this measure is not extensive and how projects impact it are not determinable yet.

  The statewide Truck Travel Time Reliability Index as of Calendar Year 2019 is 1.35. This is consistent with both the baseline and 2-Year target established in 2018.

  Initial 2 and 4-year targets were based on a trend line using the data available at the time. With 2 additional years of data to evaluate during the mid-performance cycle, it was noted that the fluctuation in the TTTR value is very slight. However, the System Performance Measures Working Group decided to adjust the 4 year target in order to ensure TDOT is able to make significant progress while setting an attainable target. This target is equal to the highest value for the last 3 years (2017-2019).

  TDOT’s 25-Year Long-Range Transportation Plan, is a policy plan that was adopted in 2016. The 25-Year Plan contains eight policy papers that cover a range of topics from demographics and employment changes and trends to travel trends and system performance. Each paper offers a set of policy recommendations influenced by peer state comparisons, TDOT’s strategic and operational goals, the Department’s Guiding Principles, and more than 20,000 community inputs gathered through public and stakeholder outreach. Important to this measure is policy paper Freight Logistics and Planning which supports the efficient movement of people and goods. TDOT is committed to provide a reliable transportation system to further this goal. As such, the adjusted target is consistent with the 25-Year Long-Range Transportation Plan and the Department’s use of current and readily available data.

  Several recently completed projects will improve reliability of freight operations. Those projects include widening of I-440 in Nashville and I-40 widening in Jackson. Additionally, there are approximately 15 railroad grant projects underway. The availability of rail freight reduces the need for trucking freight, which reduces capacity needs. Future projects include the I-24 Smart Corridor Project as well as the ITS expansion projects on I-40 near Nashville. These projects will help improve reliability for freight and other vehicles through TSMO solutions.

  TDOT’s expected performance for truck travel time reliability for calendar year 2021 is 1.32 which will outperform both the adjusted 4-year target of 1.37 and baseline of 1.35, meeting the requirements for a significant progress determination. While much of the increase in reliability may be due to changes in travel as a result of the COVID-19 pandemic, TDOT also completed several interstate improvements which may have had positive impacts on freight movement throughout the state. These improvements include the addition of truck climbing lanes and numerous repaving and widening projects including those on I-440 around Nashville.

• Data Sources:
  Tennessee 2018, 2020, 2022 Biennial Performance Report
  Tennessee 2018, 2019, 2020, 2021, 2022 HPMS Data Submittal

Significant Progress Determination

This table shows FHWA’s most recent determination for the Infrastructure performance measures.

PLEASE NOTE: Each State’s performance target assessment is based on its own State-specific target methodology and program philosophy. Therefore, conclusions should not be drawn based only on the information in the Significant Progress Determination Results table. FHWA understands that each State’s program is unique and therefore does not prescribe a methodology for States to set targets. States have the flexibility to use the methodology they deem most appropriate when setting their performance targets. 

³ The 2-year condition/performance, in 2020 Mid Performance Period Progress Report, as the baseline condition/performance, as required in 23 CFR 490.105(e)(7)(iii).