8.0 Performance Assessment

8.1 What Is Performance Assessment?

Periodic evaluation of work zone policies, processes, procedures, and work zone impacts aids in the process of addressing and managing the safety and mobility impacts of work zones. Performance assessments both at the project-level and program-level provide the required feedback to make policy, process, procedure, and program improvements and evaluate the effectiveness of work zone management strategies.

Understanding how work zones perform is a critical step in identifying how to improve work zone safety and mobility. The updated Rule (the Rule) contains provisions that address work zone performance assessment. Section 630.1008(c) of the Rule requires State Departments of Transportation and local transportation agencies[1] to "continually pursue improvement of work zone safety and mobility by analyzing work zone crash and operational data from multiple projects to improve State processes and procedures." It also recommends that, "States should maintain elements of the data and information resources that are necessary to support these activities." Section 630.1008(e) requires States to perform a process review at least every two years. This review may include the evaluation of work zone data Statewide and/or for randomly selected projects. Appropriate staff representing the various project development stages, different offices within the State, and the Federal Highway Administration (FHWA) should participate in this review. Other non-State stakeholders may also participate, as appropriate. The results of the review are intended to lead to improvements in work zone processes and procedures, data and information resources, and training programs to enhance efforts to address safety and mobility for current and future work zones. Ongoing performance assessment helps an agency gather information and identify issues and successful practices that will be useful in performing process reviews.[2]

Work zone performance assessment is not intended to require agencies to embark on a large data collection, storage, and analysis effort. The goal is to improve work zone safety and mobility by making effective use of the available data and information sources. Examples of available data and information sources include project logs, field observations, crash records, operational data from transportation management centers (TMCs) and intelligent transportation system (ITS) devices, other monitoring activities including work zone speed enforcement or citations, and complaints from the public and other stakeholders.

8.2 Objectives of Work Zone Performance Assessment

Work zone performance assessment may be performed at two levels: 1) at the program-level (i.e., assessing the performance of work zone policies, processes, and procedures); and 2) at the project-level (i.e., assessing the actual performance of the work zone and management strategies on individual projects in the field). Performance assessment includes:

• Collection of data, including project-related information and public/stakeholder perception data.
• Synthesis and analysis of data at multiple levels (i.e., project, program, local, regional, State, and national) and comparison of findings to performance metrics.
• Application of the analysis results toward continually improving work zone policy, practices, policies, processes, and procedures.

There are four key measures of work zone performance:

• Safety.
• Mobility.
• Construction efficiency and effectiveness.
• Public perception and satisfaction.

Where feasible and appropriate, these performance measures should be evaluated quantitatively. In the absence of funding and/or data availability, measures of performance may be evaluated qualitatively.

8.3 Who Are the Participants?

The end users of the performance assessment process are the management-level executive and technical staff who will use the findings to refine and/or develop new policies, processes, and procedures. However, the assessment of performance and development of recommendations will likely be performed by technical staff with input and review by different disciplines, including: planning, engineering and design, construction, maintenance, and operations. Table 8.1 shows the likely participants in performance assessment.

Table 8.1 Performance Assessment Participants

The staff who may perform the performance assessment are typically technical and may be from one of many disciplines, depending on the organizational structure of the agency. Based on the performance assessment findings, the technical staff provide input to management-level staff for policy, process, and procedural modifications.
Inputs	Input Providers
Applicable work zone policies and policy provisions – What are we assessing performance against? What are our performance objectives? Project/work zone details including project type, work zone characteristics, and influencing factors (e.g., weather, special events) and work zone management strategies used. Construction and/or transportation management plan (TMP) evaluation/effectiveness documentation for individual projects, including: Observed/measured impacts. Observed/measured effectiveness of management strategies. Comparison of what really happened versus what was planned/predicted. Lessons learned. Recommended policy/procedural changes. Information, experiences, findings, and lessons learned from other aspects of program delivery. Public outreach and stakeholder feedback.	Agency technical staff, including planners, designers, engineers, and technical specialists, who are responsible for planning and designing road projects. Field staff, including construction engineers, project engineers, and field inspectors, who are responsible for building the project and for monitoring and managing the work zone impacts of the project in the field. Contractor staff and contracting associations (e.g., ATSSA, ARTBA, AGC)[3]. General public, through public outreach and feedback. Community and business representatives. Regional stakeholders such as regional transportation providers, police, fire, emergency medical services, regional TMCs, local jurisdictions (county, city, village, township, etc.), and railroad agencies and operators. Industry and public safety associations such as trucking associations, the American Automobile Association (AAA), etc. Media agencies including newspapers and television agencies.
Outputs	Users of the Outputs
Analysis results of performance/impacts (i.e., crashes, delay, speeds, travel times, throughput, queue length, etc.). Effectiveness of management strategies. Lessons learned, trends, successes, failures, and best practices. Recommended changes/improvements to policies, processes, practices, and procedures for continuing improvement to policy, planning, design, and construction processes, and performance assessment.	Management level staff who represent the highest level of decision-making in the agency. Technical staff (planners, designers, engineers, etc.) responsible for recommending and implementing policies, processes, and procedures. Field staff (construction, inspection, etc.) and consultant/contractor staff who are responsible for identifying, implementing, and recommending policy, program, procedure, and project development and implementation changes or improvements.

8.4 Conducting Work Zone Performance Assessment

In general, the current state of work zone performance assessment is in its infancy. However, information that could be used for such an evaluation is often available or will be available in the future as agencies face increased pressure to measure and report performance to stakeholders; more technology is deployed through ITS and TMCs; and as agencies further implement the requirements and recommendations of the Rule.

The steps described in the following pages provide guidance and a method to develop and improve work zone impacts assessment and ultimately, improve work zone policies, processes, and procedures. Generally, this guidance consists of the steps identified in Figure 8.1. Some notes pertaining to the figure are presented in Table 8.2.

Figure 8.1 Work Zone Performance Assessment Process

Table 8.2 Process Notes

Input from appropriate sources (as shown in Figure 8.1) may be required during performance assessment. These include: Applicable Policies/Performance Requirements, shown as a green diamond in the diagram, represents the agency's policies and related policy provisions (i.e., policy requirements, standards, and/or guidance) and appropriate procedures, procedures, and practices that may relate to the particular activity. These policies drive decision-making on issues such as the type of performance assessment (e.g. qualitative vs. quantitative), performance measures to assess (e.g., traffic volume, average speed, travel time, queue length, total crashes), ways to measure (e.g., data on speed variance in the work zone, if available, can be used as a safety indicator), and the type of actions to take based on the assessment results. Design/Construction/Technical Specialists, shown as a green ellipse in the diagram, represents input from design engineers, traffic engineers, and construction engineers who have a good understanding of project design and construction issues. It also represents input from technical specialists in specific disciplines including highway engineers, pavement specialists, structural engineers, environmental specialists, right-of-way (ROW) specialists, and hydraulics engineers. Public/Community, shown as a green square in the diagram, represents input from the general public including motorists, other highway users, businesses, residents, neighborhood groups, etc. This input may be provided through public involvement processes, customer feedback efforts, surveys, focus groups, etc.

Step 1 of 5: Collect Project Information

The first step in performance assessment is to collect and synthesize project-level information. As shown in the process diagram, this includes information and data items pertaining to the project characteristics, project environment, TMP and its strategies, anticipated and actual work zone impacts, costs, lessons learned, and recommendations for policy and/or procedural change. Project information may be grouped as shown in Table 8.3.

Table 8.3 Project Information Categories and Examples for Performance Assessment

Project/Work Zone Details	Detailed information on the type of work and configuration of the work zone, such as: Project Type Impact based classification (e.g., significant and non-significant). Functional classification (based on type of roadwork being performed). Project and Work Zone Characteristics Location (urban, suburban, rural). Road classification. Owner agency (State, region, county, city). Length. Duration. Geometrics. Working hours. Lane closure scenarios and strategies (positive separation, lane closure, total road closure, etc.). Choice of materials (i.e., concrete or asphalt, etc.). Project cost. Contracting method (single contract vs. multiple contracts, etc.).
Influencing Factors (Context)	Factors that may have had an influence on the observed and/or measured performance impacts, such as: Travel modes served. Availability of alternative routes. Presence of other concurrent work zones nearby. Weather. Incidents. Special events. Road and pavement condition (geometrics, pavement type, road condition). Regional information (such as the existence of a regional ITS system).
Work Zone Management Strategies	The types of work zone mitigation measures and strategies utilized are an important element. These include: Temporary traffic control (TTC) strategies. Public information (PI) strategies. Transportation operations (TO) strategies. Use of ITS or other surveillance equipment for work zone monitoring and operations. Management strategies and improvements made on alternate routes. Costs associated with the management strategies and monitoring.
Performance Information	Observed and/or measured performance impacts of the work zone and the management strategies collected during the construction or maintenance activity or monitoring. This may include indirect measures. For example, speeds through a work zone in excess of the posted speed limit could be an indirect measure of safety (i.e., unsafe conditions exist even though crashes may not have been observed in the specific instance). Also includes recommendations and lessons learned.

Step 2 of 5: Collect Public Perceptions/Stakeholder Inputs

In addition to observed and/or measured performance, another important aspect of performance assessment involves public perceptions and input. Meeting the performance requirements alone does not guarantee that the public's expectation with regards to the safety and the quality of their travel is met. Public perception often turns out to be an eye-opener for many agencies. Therefore, it is important to get feedback from the public regarding the effectiveness of an agency's work zone transportation management efforts. (Similarly, as illustrated in the process flow diagrams for the other processes, it is important to appropriately involve the public and solicit their input during the various phases of project planning and development). If public perception surveys, focus groups, or other data collection efforts are conducted during project implementation, that information should be included in performance assessment. Stakeholder feedback and input through surveys and complaints may also be used to assess public perceptions at the program, regional, and/or agency-levels.

Step 3 of 5: Assess Project-Level Performance

Agencies are encouraged to perform project-level performance assessments to improve work zone policies, processes, and procedures and improve their work zone data and information resources. Most of the data needed for this assessment should be available from each project's monitoring efforts including field observations, crash data, and operational data. It is important that traffic and safety monitoring data collected during construction be documented and maintained in a consistent manner for each project. Table 8.4 presents some examples of performance measures that may be considered.

The Michigan Department of Transportation conducted an evaluation of the temporary ITS for the reconstruction of I-496 in Lansing. Source: Federal Highway Administration, ITS Deployment Analysis System Case Study 2: Michigan Department of Transportation Evaluation of the Temporary ITS for the Reconstruction of I-496 in Lansing, Michigan, April 2002. URL: http://www.camsys.com/idas/CaseStudies/CaseStudy2/caseStudyFrame.htm (Accessed 09/13/05).

Table 8.4 Example Work Zone Performance Assessment Measures

Work Zone Performance Assessment Areas	Example Measures/Impacts
Work Zone Safety Performance. This aspect of work zone performance addresses both traffic and worker safety. Measures are typically obtained over/during a period of time.	Traffic crash statistics. Circumstances leading to the occurrence of crashes. Influencing factors. Average speeds and speed variance. Worker fatalities and injuries. Work area incidents/near misses.
Work Zone Mobility Performance. This aspect of work zone performance provides a representation of the ease, convenience, and efficiency of the transportation system through, in, and around the work zone. Specifically, work zone mobility pertains to moving road users smoothly through or around a work zone area with a minimum delay compared to baseline travel when no work zone is present.	Delay. Speed. Travel time. Queue length. Vehicle and/or person throughput. Business/community accessibility.
Construction Efficiency and Effectiveness. This aspect of work zone performance provides an assessment of the efficiency and the effectiveness of the actual construction project itself. Even though the efficiency and effectiveness of construction may seem like an unrelated aspect, it is key to the safety and mobility performance of work zones. For example, project delays cause the impacts of the work zones to last longer, and poor quality work require repetitive fixes and repairs at a later stage.	On-time completion. Cost-efficiency/effectiveness. Quality of work. Needs satisfaction (i.e., project addressed roadway issues/problems).
Public Perception. This aspect of work zone performance provides an indication of what the traveling public feels about the performance and impacts of work zones. In spite of the best possible work zone designs and management strategies used, negative public perception about a project may damage the image of a transportation agency, perhaps even resulting in project stoppage. Public perception data can be collected before, during, and after the implementation of road projects. Documentation of public input may yield information that may be useful for implementing work zone designs and strategies that resonate with what the public wants. Public perception data may be collected through surveys (telephone, Internet, roadside), focus groups, and public meetings.	Calls/comments received – pro and con. Customer satisfaction indexes. User perceptions about the safety and mobility of the work zone. Use of certain management strategies (e.g., web site visits). User perceptions about the effectiveness of certain management strategies.

Step 4 of 5: Synthesize and Analyze Data for Program-Level Assessment

This step represents the synthesis and analysis of performance assessment data and information gathered from the various sources. This data may be aggregated and collated to perform analysis and make inferences/recommendations at the project, program, regional, State and/or national levels. Appropriate data analysis tools may be used for the assessments (e.g., spreadsheets, statistical analysis tools, simulation software).

Project-level work zone performance data serve as the basis for program-level and other higher-level assessments. The flow of data to and from the project-level to other higher levels will likely require a few years of data collection at the project-level to establish critical masses and statistically significant trends and inferences. Such data flows from the project-level to other higher levels and vice-versa should ideally reflect a bottom-up as well as a top-down flow structure. The bottom-up flow represents the incremental flow of basic data and the associated analyses from the project-level through the higher levels. The top-down flow represents the reverse data flow of national-level trends, figures, and analyses that may be used for decision-making at the State, regional, program and project-levels.

The lack of sufficient before and after data, especially before data, is often cited as a hindrance to performance measurement assessments. The establishment of a comprehensive work zone performance measurement framework and sustained implementation of work zone performance measurement will eliminate such obstacles. The four areas of interest in work zone performance assessment are safety, mobility, construction efficiency and effectiveness, and public perception and satisfaction. These are presented in Table 8.3, along with examples of performance measures that fall under each of the areas.

Data collection and analysis will likely involve a combination of existing/available sources and methods, and ideally, a performance tracking process/program specifically intended for work zones. Some of the data collection methods/sources include:

• Transportation planning and forecasting models.
• Transportation and traffic simulation models.
• Field observations.
• Specific field measurements, either infrastructure based (e.g., dynamic queue detection and management) or probe vehicle based (e.g., floating car study).
• Crash records.
• Traffic records.
• Construction project logs.
• Construction project plans, designs, and estimates.
• Traffic incident management and response logs.
• Archived ITS data from existing deployed systems.
• Use of ITS data from work zone specific ITS systems.
• In-vehicle data from Intelligent Vehicle (IV) systems.
• Previously available data and reports.
• TMP and TMP evaluation findings.
• Interviews.
• Surveys.
• Focus Groups.

Step 5 of 5: Evaluate and Revise Work Zone Impacts Assessment and Management Process/Practices/Procedures

This is the final step in the performance assessment process, where the information from Steps 3 and 4 are used to develop lessons learned and to evaluate and revise policies, processes, practices, and/or procedures. Items that should be assessed/reassessed and revised as necessary include:

• Work zone types (i.e., significant/non-significant projects, type of roadwork being performed, etc.).
• Work zone management strategies.
• Programs (e.g., training).
• Policies (e.g., for maintenance of traffic).
• Procedures (e.g., for identifying significant projects or developing TMPs).
• Standards (e.g., design standards, contract specifications).
• Thresholds/benchmarks.
• Systems planning process.
• Preliminary engineering and design processes.
• Construction process.
• Performance assessment process.

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