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21st Century Operations Using 21st Century Technologies

2019 Road Weather Management Performance Measures Update

Chapter 1. Introduction

Since 2006, the Federal Highway Administration's (FHWA's) Road Weather Management Program (RWMP) has conducted a periodic assessment of program effectiveness in improving the performance of the transportation system during adverse weather conditions. Assessments of the program performance were conducted and documented in 2009,1 2012,2 2015,3 and 2017.4 These updates reviewed program initiatives and major accomplishments; assessed the continued suitability, strengths, and weaknesses of existing measures for evaluation program performance; and incorporated new measures, as appropriate, that reflected current and future program initiatives. The 2019 Road Weather Management Performance Measures Update is a continuation of this periodic review of the RWMP's performance and an update to the 2017 report.

Objectives of the Report

The performance measures update and associated reports allow the RWMP to evaluate its progress and effectiveness in accomplishing its goals and to assess the United States' overall capability with respect to road weather management. The report also serves as a resource and outreach product to advance the importance and widespread implementation of road weather technologies. This assessment helps communicate the overall success of the RWMP and identify areas that need more focus, support, or outreach. The 2019 report presents the latest results of the RWMP's performance measures, highlights significant changes or improvements from the last update, and lists recommendations on future focus areas for the RWMP.

Road Weather Management Program Goals, Objectives, and Key Products

The RWMP strives to better understand the ways weather impacts roads and to promote successful strategies and tools to mitigate those impacts. In broad terms, the program achieves its goals through stakeholder coordination; road weather research and development; technology transfer, training, and education; and performance management and evaluation. The RWMP is guided by eight program objectives used to determine technical direction and activity. The objectives are:

  1. Build and sustain relationships with multidisciplinary partners to expand road weather management deployments.
  2. Ensure road weather management investments improve highway performance.
  3. Advance the transportation, weather, and research communities' use of and reliance on fixed and mobile road weather observations.
  4. Advance the state of the art for mobile sensing and integrating vehicle data into road weather applications.
  5. Advance the state of the practice by promoting tailored management strategies for different regions.
  6. Improve integration of weather-related decision support technologies into traffic operations and maintenance procedures.
  7. Advance the state of the practice by raising road weather management capabilities and awareness across the transportation and weather communities.
  8. Increase engagement of the operations community with the weather resiliency and sustainability communities.

To support these objectives, the RWMP has produced several research products and services. Some of the most recent products include:

  • Every Day Counts (EDC-5) Initiative—Weather-Responsive Management Strategies (WRMS). The strategies focus on using mobile and connected vehicle data from traffic and maintenance management during weather events. Building from the EDC-4 Weather Savvy Roads innovation, FHWA is assisting agencies in the implementation of various activities and products.
  • Road Weather Management Capability Maturity Framework (RWM CMF) Workshops. The RWMP has conducted a total of 16 RWM CMF workshops in 15 States. These workshops help agencies evaluate their current capabilities in managing the transportation system during road weather events and assist in creating a roadmap of prioritized actions for increasing capabilities across the six sectors of the CMF.
  • National Highway Institute (NHI) Road Weather Management Courses. The RWMP is updating and converting the road weather management Consortium for ITS Training and Education (CITE) courses into a format to be delivered by the National Highway Institute. The Road Weather Information System (RWIS) Equipment and Operations course is available in the Institute catalogue and is free to the public.
  • Weather-Responsive Traffic Management (WRTM) Implementation Projects. The RWMP worked with the Delaware DOT and Washington State DOT to evaluate the Guidelines for Deploying Connected Vehicle-Enabled Weather Responsive Traffic Management Strategies.

Research Approach

The research team's approach for the 2019 update included a review of the 2017 update, as well as the program's current objectives, activities, and products. The team then developed a plan for conducting the 2019 update and provided recommendations for presenting the results. In general, the reporting period for the performance updated is from January 2017 to mid-year 2019. These categories of sources provided data elements for the performance measures:

  • RWMP Records. The FHWA RWMP's research, training, and stakeholder engagement activities are documented in its records. These data represent the location and extent of RWMP activities.
  • State Department of Transportation (DOT) Survey. A targeted survey of State DOTs provided data on the current practices and capabilities for road weather management around the country. The survey was completed by 39 State DOTs, which is one State less than responded to the 2015 and 2017 updates. Figure 1 illustrates the distribution of the survey respondents.
  • Agency Sources, Literature Reviews, and Internet Searches. Road weather data from other Federal, State, and local agency sources, along with research institutions (e.g., databases, literature reviews, case studies, and publications) provide additional inputs into the performance measure update—especially information pertaining to system outcomes and specific case studies or evaluations of road weather management strategies.
  • Additional Data Sources. Other data resources are used to supplement the primary sources listed above to meet the data requirements for the performance measure update. In many cases, these data elements are used to support the findings for the performance measures.
Figure 1. United States Map: The distribution of states that responded to the 2019 Road Weather Management State DOT Survey are shown in a map depicting the 50 states.  The survey was completed by 39 states and was targeted to learn about the current practices and capabilities for road weather management around the country.  In the bottom right half of the map, the biggest cluster of states that did not participate include most of the southern states.
Figure 1. Map. States that responded to the 2019 Road Weather Management State DOT Survey.

For this update, the research team designated each performance measure as an output (direct effort of RWMP), an outcome (response from transportation agencies and other stakeholders), or an impact (changes in transportation system performance including user, agency and societal costs and benefits). After designating each performance measure, the team identified data sources, related activities, and the strengths and weaknesses of each measure. By looking beyond each measure's latest result and analyzing the components that factored into the result, the research team was able to take a more holistic look at the RWMP's progress and successes. Table 1 summarizes the 25 performance measures in this way.

Table 1. Data Sources, Related Activities, and Strengths and Weaknesses of Each Performance Measure
PM # RWMP Performance Measure Type of Measure Primary Data Source Related Activities in 2017-2019 That May Influence the Measure Link to Activities Measure Strengths (S) & Weaknesses (W)
Objective 1: Build and sustain relationships with multidisciplinary partners to expand road weather management (RWM) deployments.
1 Number of agencies participating in road weather R&D projects Output FHWA RWMP (interviews with staff and review of R&D program)
  • EDC-4
  • EDC-5
  • Weather Data Environment
  • Weather-Responsive Traffic Management (WRTM) implementation support activities
High S: Clearly illustrates the collaborative nature of RWMP R&D.

W: The quantification of the measure is very sensitive to how "participation" is defined.

2 Number of agencies participating in and benefiting from RWMP stakeholder meetings/workshops Output RWMP records
  • RWM stakeholder meetings, 2017 and 2018
  • RWM CMF Workshops, 2017 and 2018
  • WRTM stakeholder meetings, 2017
  • EDC-4 Weather Savvy Roads Innovation
  • EDC-5 Weather Responsive Traffic and Maintenance Management Innovation
High S: Illustrate the diversity of agencies participating in RWM workshops; workshop participants benefit from the peer-to-peer interaction and additional training.

W: While feedback on the workshops is uniformly positive, it is unclear how to quantify the benefits of the workshop to the participants.

Objective 2: Ensure that road weather management investments improve highway performance.
3 Number of agencies that collect and report road weather-related performance measures to the public (i.e., winter severity index, mobility index) Outcome State DOT Survey as well as internet research All activities can support this measure, but direct attribution of specific activity is difficult High S: Shows the improvement in agency transparency on RWM efforts.

W: Lack of widely accepted standards for measuring success of snow and ice control activities.

4 Number of agencies that have a process for evaluating the return on investment (ROI) or net benefit of their RWM investments Outcome State DOT Survey Compendium and technical briefs on benefit-cost analysis for road weather management Medium S: Shows agency engagement in gauging its own performance for continuous improvement.
5 Reductions in agency costs of weather-related maintenance and operations activities Impact Highway Statistics publication series and internet research for case studies All activities can support this measure, but direct attribution of specific activity is difficult Medium S: With States' budget constraints, case studies and data showing potential cost savings may encourage more States to implement road weather strategies.

W: While individual case studies and national trends are available, linkage to program activities is difficult.

6 Reduction in number and types of fatalities and crashes attributed to adverse weather, nationally Impact FARS, NHTSA databases and internet research for case studies All activities can support this measure, but direct attribution of specific activity is difficult High S: With road weather as part of the EDC initiative, case studies and safety effects of road weather strategies are important to show.

W: While individual case studies and national trends are available, linkage to program activities is difficult.

7 Reductions in extent of capacity losses and delays due to fog, snow, and ice events, including freight Impact Internet research, Case studies All activities can support this measure, but direct attribution of specific activity is difficult High W: No clear national-level dataset on this topic. Localized case studies serve as a surrogate approach.
8 Increase in travel time reliability or decrease in variability due to road weather management strategies during adverse weather scenarios Impact Internet research, Case studies All activities can support this measure, but direct attribution of specific activity is difficult High W: No clear national-level dataset on this topic. Localized case studies serve as a surrogate approach.
9 Reduction in tons of salt or chemical usage in the U.S. normalized by winter severity index Impact United States Geological Survey Minerals Yearbook: Salt (2006-2015) and internet research, Salt Institute, and AASHTO Standing Committee on Maintenance All activities can support this measure, but direct attribution of specific activity is difficult High W: While individual case studies and national trends are available, linkage to program activities is difficult. The lack of a common winter severity index makes temporal comparisons difficult.
Objective 3: Transportation, weather, and research communities use and rely on fixed and mobile road weather observations.
10 Number of State DOTs participating in MADIS program Outcome NWS and RWMP records
  • Support Clarus transition to MADIS
  • Data sharing agreements support
High S: Directly shows if the broad national scope of Clarus transitioned to State implementation of MADIS.

W: MADIS system is currently still in development stages with NOAA. Hence usage is still limited by DOTs

11 Number of State DOTs that subscribe to road weather products and services Outcome ITS Deployment Statistics and State DOT Survey
  • Road Weather CMFs
  • Pathfinder
  • Integrated Mobile Observations (IMO)
High S: Directly shows growth in agency use of weather and road weather information.
12 Number of State DOTs collecting mobile observations of road weather data from vehicle fleets Outcome State DOT Survey
  • IMO program
  • Standards support (connected vehicles, NTCIP 1204, J2735 SE)
High S: Directly shows growth in agency use of mobile data for road weather. Also identifies the type of data that are collected from maintenance vehicles, as well as from what percentage of the applicable fleets.

W: Use of mobile data standards is still in its infancy

13 Number of State DOTs reporting the use of Environmental Sensor Stations (ESS) in operations and maintenance activities Outcome FHWA's RWMP records, ITS Deployment Statistics, State DOT Survey, Aurora Pooled Fund program
  • IMO — how permanent and transportable ESS data are enhanced by mobile ESS
  • IMRCP — how permanent ESS data are used in modeling the effects of weather of on the roads
  • WxDE — how quality checked ESS data enhances the correct usage of data
Medium S: Directly shows and tracks the usage of ESS to support management and maintenance decision-making.
Objective 4: Advance the state of the art for mobile-sensing and integrating vehicle data into road weather applications.
14 Number of/percentage of responding agencies using mobile data-based applications in road weather management Outcome RWMP records and State DOT Survey
  • IMO program
  • EDC-5 WRMS Program
High S: Directly shows growth in agencies' use of mobile data-based applications for RWM and growth in their partnership with new groups involved in RWM with such applications.
Objective 5: Advance the state of the practice by promoting tailored management strategies for different regions.
15 Number of States disseminating advisory weather and road weather information to travelers Outcome ITS Deployment Statistics, State DOT Survey, State statistics
  • EDC-4 Pathfinder initiative
  • EDC-5 WRTM implementation support activities
  • Messaging guidelines for road weather
High S: Direct measure to assess adoption of road weather messaging around the country
16 Number of agencies using control and treatment strategies during weather events Outcome ITS Deployment Statistics and State DOT Survey
  • EDC-4 Pathfinder initiative
  • EDC-5 WRTM implementation support activities
Medium S: Direct measure to assess adoption of road weather control around the country.

W: Diversity of strategies and application scenarios make this measure difficult to quantify effectively.

17 Number of agencies that coordinate with their local forecast offices for road weather management and operations Outcome State DOT Survey
  • Pathfinder Initiative
  • Road Weather CMF
High S: Reflects agency's commitment to enhancing the performance of road weather management and operations activities.
Objective 6: Weather-related decision support technologies are integrated into traffic operations and maintenance procedures.
18 Number of agencies adopting MDSS technologies and methods Outcome State DOT Survey and MDSS Pooled Fund program
  • RWM Stakeholder Meeting
Low. No recent activities relating to MDSS S: Directly shows growth towards advanced approaches to managing maintenance decisions and operations during inclement weather.
19 Number of agencies using other weather-related decision support tools Outcome State DOT Survey
  • IMRCP Phase 2 and 3
  • Tools for Operations Benefit Cost Analysis
  • AMS for RW-CV applications
  • WxDE
High S: Directly shows growth in agency use of decision support tools in road weather.
20 Number of agencies reporting use of appropriate analysis tools to factor weather impacts and strategies Outcome State DOT Survey
  • AMS for RW-CV applications
  • IMRCP
Medium S: Directly shows growth in agency use of analysis, modeling, and simulation tools in road weather.

W: Limited program activity in this area makes it difficult to attribute changes to program.

Objective: 7 Advance the state of the practice by raising road weather capabilities and awareness across the transportation and weather communities.
21 Number of agencies and attendees who have taken any of the sponsored RWMP training courses and workshops Output FHWA RWMP records (for CMF workshops) and attendance records from CITE, University of Maryland
  • RWM CMF workshops
  • CITE training courses
High S: Directly illustrates the popularity and demand for RWMP training products.
22 Number of agencies and participants in RWM webinars led by the RWMP Output FHWA RWMP records and records from the ITS Professional Capacity Building (PCB) Program and other webinar sponsors/venues
  • RWMP webinars
  • National Transportation Operations Coalition, T3, and Talking Freight webinars
High S: Directly illustrates the popularity and demand for RWMP outreach topics.
23 Number of agencies that have participated in or conducted RWM capability maturity assessment exercises Outcome RWMP records
  • RWM CMF
  • AASHTO Capability Maturity Model
High S: Shows growth in agency use of capability maturity assessment tools and commitment to establish RWM as a core function.
24 Number of meetings, site visits, or venues where RWM presentations/ briefings were made Output FHWA RWMP records
  • RWMP partnership activities with partners such as pooled funds, TRB, ITS America, AASHTO, NWS, NOAA, Office of the Federal Coordinator for Meteorology, World Road Association-PIARC
  • National Dialogues on Highway Automation
High S: Indicates the reach of the technical transfer activities undertaken by the program.

W: It is difficult to correlate program success using the number of meetings staff are present at. A large conference with many attendees may present general information to a broader audience, while a smaller site visit may cover information more relevant to a specific agency.

Objective 8: Operations community is engaged with weather resiliency and sustainability communities.
25 Number of agencies conducting vulnerability/risk assessment or developing/implementing resiliency plans for their RWM infrastructure and processes to respond to extreme weather Outcome State DOT Survey
  • FHWA Extreme Weather Adaptation activities
High S: Shows the growth in agency awareness for weather resiliency, in managing extreme weather and improving the resiliency of operations.

W: 2017 results indicate this is still an emerging area but limited activities have taken place within the program supporting this measure.

Performance Measure Mapping

For this report, each of the 25 performance measures are grouped into one of four categories:

  1. Road weather management impacts
  2. Application of road weather management tools and technologies
  3. Road weather management capacity building
  4. Partnerships and stakeholder collaboration

By associating performance measures with one or more of these categories, the RWMP goes beyond simply listing each performance measure result and can anecdotally cover the successes of the program. Table 2 maps each performance measure to the appropriate categories. For a detailed analysis of findings by performance measure, see Appendix B: Findings by Measure.

Table 2. Performance Measure Mapping
PM # RWM Impacts Assessment Application of RWM Tools & Technologies RWM Capacity Building Partnerships & Stakeholder Collaboration
1. Number of agencies participating in road weather R&D projects No Value No Value X X
2. Number of agencies participating in and benefiting from RWMP stakeholder meetings/workshops No Value No Value X X
3. Number of agencies that collect and report road weather-related performance measures to the public (i.e., winter severity index, mobility index) X No Value No Value No Value
4. Number of agencies that have a process for evaluating the return on investment (ROI) or net benefit of their RWM investments X No Value X No Value
5. Reductions in agency costs of weather-related maintenance and operations activities X No Value No Value No Value
6. Reduction in number and types of fatalities and crashes attributed to adverse weather, nationally X No Value No Value No Value
7. Reductions in extent of capacity losses and delays due to fog, snow, and ice events, including freight X No Value No Value No Value
8. Increase in travel time reliability or decrease in variability due to road weather management strategies during adverse weather scenarios X No Value No Value No Value
9. Reduction in tons of salt or chemical usage in the U.S. normalized by winter severity index X No Value No Value No Value
10. Number of State DOTs participating in MADIS program No Value X No Value X
11. Number of State DOTs that subscribe to road weather products and services No Value X No Value No Value
12. Number of State DOTs collecting mobile observations of road weather data from vehicle fleets No Value X No Value No Value
13. Number of State DOTs reporting the use of Environmental Sensor Stations (ESS) in operations and maintenance activities No Value X No Value No Value
14. Number of/percentage of responding agencies using mobile data-based applications in road weather management No Value X No Value No Value
15. Number of States disseminating advisory weather and road weather information to travelers No Value No Value X No Value
16. Number of agencies using control and treatment strategies during weather events No Value No Value X No Value
17. Number of agencies that coordinate with their local forecast offices for road weather management and operations No Value No Value X No Value
18. Number of agencies adopting MDSS technologies and methods No Value X No Value No Value
19. Number of agencies using other weather-related decision support tools No Value X No Value No Value
20. Number of agencies reporting use of appropriate analysis tools to factor weather impacts and strategies No Value X No Value No Value
21. Number of agencies and attendees who have taken any of the sponsored RWMP training courses and workshops No Value No Value X No Value
22. Number of agencies and participants in RWM webinars led by the RWMP No Value No Value X X
23. Number of agencies that have participated in or conducted RWM capability maturity assessment exercises No Value No Value X No Value
24. Number of meetings, site visits, or venues where RWM presentations/ briefings were made No Value No Value X X
25. Number of agencies conducting vulnerability / risk assessment or developing / implementing resiliency plans for their RWM infrastructure and processes to respond to extreme weather No Value X X No Value

Organization of the Report

This report is organized so that each chapter can stand alone. Each chapter covers one of the four categories described in the previous section.

The report also includes two appendices:

1 Federal Highway Administration, Road Weather Management Program Performance Metrics: Implementation and Assessment. FHWA-JPO-09-061, 2009. Available at: http://ntl.bts.gov/lib/31000/31600/31611/14492_files/14492.pdf. [ Return to Note 1 ]

2 Federal Highway Administration, Road Weather Management Performance Measures—2012 Update. FHWA-JPO-13-87, 2013. Available at: http://ntl.bts.gov/lib/51000/51000/51065/26615E33.pdf. [ Return to Note 2 ]

3 Federal Highway Administration, 2015 Road Weather Management Performance Measures Survey, Analysis, and Report. FHWA-HOP-16-001, January 2016. Available at: https://ops.fhwa.dot.gov/publications/fhwahop16001/fhwahop16001.pdf. [ Return to Note 3 ]

4 Federal Highway Administration, 2017 Road Weather Management Performance Measures Update. FHWA-HOP-17-048, October 2017. Available at: https://ops.fhwa.dot.gov/publications/fhwahop17048/index.htm. [ Return to Note 4 ]

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