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42 Conclusions and research needs are discussed for each of the four performance areas and for the topics of collaboration and resources. Conclusions Forty-one DOTs responded to all four parts of the survey, and several more DOTs responded to one, two, or three parts. About 16 MPOs responded to the survey. In general, most states have the data they need and are prepared to process it to support performance reporting. All of the DOTs responding have the data for bridge condition measures. Some DOTs cannot meet all the needs related to pavement condition and mobility measures. States are least likely to be prepared to process and produce measures for the mobility performance areas when compared to the others. Figure 6-1 presents percentages for the preceding measures. Current State Data Collection In general, State DOTs have most of the data they need to report on measures. DOTs report being the most prepared in the bridge condition and safety areas, closely followed by pavement, and then mobility. â¢ Bridge. All who responded to the bridge condition part of the survey have all the data nec- essary to report on all of the bridge condition measures. Most of the states (44) reported that they collect the data for the bridge measures internally. For all of the bridge condition measures, 22 of the DOTs responded that they are coordinating with MPOs and local govern- ments regarding collection. â¢ Pavement. Most states have the data they need for pavement condition reporting. The num- ber of DOTs with all data to support pavement measures varies from 44 for IRI on the NHS Interstate to 36 for cracking on NHS non-Interstate. In all cases, the number of states having all data for each of the measures is slightly less on the non-Interstate NHS, when compared to the Interstate NHS. Approximately one-half of the DOTs indicated that they collect the data internally. DOTs might have been considering the requirements in the NPRM versus the final rule. For example, the NPRM required collection of pavement data in both directions on the Interstate system while the final rule only requires the data in one direction. â¢ Mobility. All of the DOTs have the annual VMT data to support mobility measures. Regard- ing local vehicle occupancy, 34 DOTs indicate that they do not have the data to support the measure. Transit measures are the most frequently reported by State DOTs (26 reporting). All States, except for one, will be using the National Performance Management Research Data Set (NPMRDS) provided by the FHWA to obtain speed. Twenty-five DOTs are coordinating with C H A P T E R 6 Conclusions and Future Research Needs
Conclusions and Future Research Needs 43 their MPOs on speed data collection. Most of the required data for the mobility measures is available to the DOTs and MPOs, so they are prepared to process the data and produce the required measures. â¢ Safety. In general, DOTs have most of the data required for the four safety measures. For Fatalities on All Public Roads, only 1 out of the 42 States responding does not have the data. Regarding Serious Injuries on All Public Roads, four States do not have the data. Only two States report that they do not have the data to support Rate of Serious Injuries and Fatalities per 100 million VMT on all Public Roads. Most State DOTs are collecting the data in house. One-half of the States obtain the data in house, and the other one-half obtain the data from other agencies. When asked how they plan to handle VMT on all public roads, some State DOTs responded that they are collecting traffic on all public roads; however, most indicated that they do not have the volume data readily available. Twenty-six States indicated that they are collaborating with local government to obtain the data. Data Analysis and Tools Most States are using specialized tools and technology to analyze and report their data. Specialized tools and data are used most in the pavement and bridge performance areas (33 and 29 states, respectively). The next highest use of specialized tools occurs in the mobility area (28 State DOTs). Twenty-four states report using specialized tools in the safety area. More DOTs are using specialized tools and visualization methods for reporting on perfor- mance in the pavement area than any other area. Mobility tools for reporting are used in 22 states, followed by safety tools (18) and bridge area (18). DOTs reported using tools to analyze data in the bridge area at a much higher rate (29) than they use tools to report bridge condi- tion (18). DOTs use specialized tools for mobility and safety performance areas, slightly more for data analysis than for reporting on performance. Target Setting State DOTs are most advanced with respect to developing target-setting methods for safety measures, with 40 reporting they have methods in place. Only 13 of the states have developed methods for mobility target setting. Twenty-seven of the states have developed bridge target- setting processes. Fifty-one percent of the DOTs have set a process for target setting for pave- ment. For all four performance areas, most targets are based on historic trends, models into the future or goals. Most DOTs define their targets as realistic (i.e., in line with plans, but doable per the survey), as opposed to the other two choices (i.e., minimum or conservative (easy to meet) and stretch or aspirational). Collaboration Collaboration with partners is a key success factor for performance management. Coordina- tion is occurring with MPOs in the safety area and slightly less so for mobility, but no significant Figure 6-1. DOTs prepared to process the data and produce the required measures.
44 Analyzing Data for Measuring Transportation Performance by State DOTs and MPOs coordination is occurring for pavement and bridge measures. DOTs report the most developed collaboration with MPOs relates to safety measures, with the next most developed area being mobility, followed by the pavement and bridge condition areas. Collaboration is most developed for bridge condition measures, compared to pavement condition measures. Proficiency of Staff The survey results show that DOTs need improved proficiency in staff, consultants, and tool capability for all performance areas, with mobility having the highest need, followed by bridge, pavement, and then safety. Thirty-nine DOTs reported that their staffs are fully proficient with data collection, analysis, and reporting for bridge condition measures. Similar results are observed for the pavement condition measures. Thirty-three DOTs reported that their staffs are fully proficient with data collection, analysis, and reporting for pavement condition measures. In the case of mobility measures, DOTs report that consultant technical capability is higher than staff capability. Safety is the only performance area where DOTs reported the highest percent- age in the fully capable and proficient column for all three areas (technical capability of staff, consultants, and current tools). Resources State DOTs reported they have the most resources to handle bridge condition measures (with only one state with insufficient resources), followed by pavement condition, safety, and mobility. Twenty-one states report having insufficient resources to handle data to support mobility measures. Gaps in Data and Tools to Support Performance Measurement In general, data and tools to support pavement and bridge condition are well developed. Direct field data collection and well-vetted predictive models have helped states improve their asset investment decisions over the course of several decades. Even so, many states lack the ability to rigorously assess gaps in asset condition relative to targets, identify and mitigate risks, set priorities, and project how investments will influence future condition. Gaps in the devel- opment of performance measures for congestion, delay, reliability, and freight will require additional support. A significant area of concern among State DOTs and MPOs is setting performance targets. Data Collection â¢ Bridge. States have no major gaps in data, but some concerns about the data being collected. Concerns include collection every 2 years being a challenge, lack of clear direction on how to calculate the area of a culvert, and confusion about the good/fair/poor rating. MPOs are relying heavily on the States to provide them with bridge condition data. â¢ Pavement. Some States reported data gaps, especially in relation to cracking data on NHS Inter- states and non-Interstate roadways. DOTs might have been considering the requirement to collect the pavement data in both directions on the Interstate system, while the final rule only requires the data in one direction. MPOs are relying heavily on the States to provide them with pavement condition data. â¢ Mobility. States and MPOs have numerous concerns about collecting data to support mobil- ity and air quality measures. The comments and concerns related to the mobility measures are more significant and include segmentation and PSL. VMT on non-Interstate NHS may be an issue for many. â¢ Safety. DOTs and MPOs reported very few challenges with the collection of data to support safety measures.
Conclusions and Future Research Needs 45 Data Analysis and Tools Across the board, less than half of State DOTs responding have needs for tools and technology for analyzing performance data. The highest number of needs relate to pavement, followed by the mobility, bridge, and safety performance areas. In all cases, there appears to be slightly less need for reporting tools, compared to analysis tools. The highest needs for reporting tools are in the mobility area. The lowest needs are in pavement and safety. Target Setting DOTs have the most data gaps pertaining to setting targets for mobility measures and the least related to bridge condition. Data gaps for setting targets in the pavement and safety areas are reported by approximately one-third of all states. In the area of target setting, State DOTs lack trend data, particularly for non-Interstate NHS. Additional guidance or standardization related to analysis techniques may be needed for the following: â¢ Conflation for speed and volume, â¢ HPMS as a data source for VMT, â¢ Segmentation (Traffic Message Channels (TMC) and linear referencing systems (LRS)), â¢ Processing pavement data at one-tenth of a mile increments, and â¢ Timeliness of the NHTSA FARS data. The survey respondents were commenting on the NPRM, where the requirements related to metrics reporting were not yet clear. The final rule and subsequent guidance from FHWA clarifies that States do not need to complete conflation of their networks, which simplifies the requirement significantly. Rather, states must enter the travel time metrics into HPMS, and the combination of these metrics with volumes occurs at the FHWA level. However, a State may still want to analyze their data to prepare for target-setting analysis, which would require preparing and combining speeds and volumes, which would then require conflation. Future Research Needs Research needs are summarized by topic. Bridge Successful Practices â¢ Synthesis on successful practices, including what local and other transportation agencies are doing. Tools â¢ Research on development of deterioration models, rates and curves, and user costsâto fore- cast future needs and determine the effectiveness of different preventive actions/measures. â¢ Research and development of tools for analysis and reporting that are spatial, standardized, and visual; allow for statistical tracking; and are user-friendly (this could be in BrM). Deterioration and Degradation â¢ Continued research on detrimental effects of truck traffic volumes and axle weights. â¢ Research on effect of underlying factors (future funding, deterioration, projected costs of future construction, etc.). â¢ Research on enhanced degradation curves representing the population of bridges within a stateâs inventory.
46 Analyzing Data for Measuring Transportation Performance by State DOTs and MPOs Pavement Tools â¢ Research and tools for automated cracking detection. â¢ Research on how pavement tools can be more automated, include forecasting (2 and 4 years), and be better integrated. Data Processing and Forecasting â¢ Research and guidance on processing at one-tenth per mile increments. â¢ Research on forecasting conditions for cracking, rutting, and IRI (especially without historical data (i.e., local system)). Analysis â¢ Research into an AASHTOWare product to convert a Stateâs HPMS dataset to pavement measures. â¢ Research on more accurate performance curves, and reset values for preventive maintenance treatments. â¢ Research on composite distress scoring methods that result in smooth actual measured deterioration curves. â¢ Research on developing deterioration curves for Pavement Preservation treatments (chip seal, scrub seal, etc.). Mobility Templates State DOTs would like to see FHWA-developed templates. Technical IssuesâConflation and Segmentation Further study may address and resolve state issues pertaining to segmentation and conflation, including consideration of a standardized approach. It is possible that the new release of National Performance Management Research Data Set will address some of these issues. The survey respondents were commenting on the Notice of Proposed Rule Making where the requirements related to the reporting of metrics were not yet clear. The final rule and subsequent guidance from FHWA clarifies that states do not need to complete conflation of their networks, which simplifies the requirement significantly. Rather, states must enter the travel time metrics into HPMS and the combination of these metrics with volumes occurs at the FHWA level. How- ever, a state may still want to analyze their data to prepare for target-setting analysis, which would require preparing and combining speeds and volumes, which would then require conflation. Tools Research and development of more tools to support congestion management processes. Research to develop better tools for forecasting heavy vehicle traffic. Training Research and development of skill sets, including educational programs related to data analytics. Nonmotorized Research, synthesis, and development of capability for nonmotorized data collection and esti- mation (such as bicycle and pedestrian). Research related to nonmotorized level of service measures.
Conclusions and Future Research Needs 47 Vehicle Occupancy Research and methods regarding vehicle occupancy measures and estimates. Forecasting Research on: âWhat are the variables that are most important for forecasting: mobility in general, passenger versus freight, trucks versus commodities.â New Data Sources Vast amounts of traffic operations data are available through sources like INRIX and Waze. Research to provide better understanding of this information, along with other data sources, will help states better forecast future values for mobility. Safety Tools â¢ Research and develop an HSIP online tool and an HSP online tool, which automatically updates the FARS database. â¢ Research needs for better analytical, spatial, robust tools for analyzing trends and forecasts. â¢ Research expanding SafetyAnalyst and update databases to cover local roads. â¢ Syntheses on the state of the art in application of SafetyAnalyst and research into data to support use of SafetyAnalyst. Forecasting â¢ Research regarding forecasting crashes and effects of countermeasures. Include approaches for assessing future projections based on contributing factors beyond historical crashes/ injuries data. External Factors â¢ Investigation of external factors affecting targets (such as age of vehicle fleet, economy, growth, urbanization, rural population density, education and poverty levels, automation and vehicle technology, legislation, etc.). â¢ Research on having a better understanding of when autonomous vehicles will become more mainstream and how this will affect reduction of fatalities and serious injuries would assist with future modeling and forecasting. Target Setting â¢ A synthesis on target-setting methodsâit also would be useful to review target setting in a few years to assess how well targets were estimated. General Research The lists above were compiled primarily from the surveys. It would be very helpful to all states and MPOs if a study could be undertaken to answer and address all of the concerns and issues. Many of the research needs may already be resolved, or study is underway to address them. In addition, it would be interesting to conduct a similar survey in 2 years to assess whether the states and MPOs have improved the methods of data collection, analysis, and reporting to support performance measurement.