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Strategies for Work Zone Transportation Management Plans (2020)

Chapter: Chapter 12 - Other Practices

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Suggested Citation:"Chapter 12 - Other Practices." National Academies of Sciences, Engineering, and Medicine. 2020. Strategies for Work Zone Transportation Management Plans. Washington, DC: The National Academies Press. doi: 10.17226/25929.
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Suggested Citation:"Chapter 12 - Other Practices." National Academies of Sciences, Engineering, and Medicine. 2020. Strategies for Work Zone Transportation Management Plans. Washington, DC: The National Academies Press. doi: 10.17226/25929.
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Suggested Citation:"Chapter 12 - Other Practices." National Academies of Sciences, Engineering, and Medicine. 2020. Strategies for Work Zone Transportation Management Plans. Washington, DC: The National Academies Press. doi: 10.17226/25929.
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Suggested Citation:"Chapter 12 - Other Practices." National Academies of Sciences, Engineering, and Medicine. 2020. Strategies for Work Zone Transportation Management Plans. Washington, DC: The National Academies Press. doi: 10.17226/25929.
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Suggested Citation:"Chapter 12 - Other Practices." National Academies of Sciences, Engineering, and Medicine. 2020. Strategies for Work Zone Transportation Management Plans. Washington, DC: The National Academies Press. doi: 10.17226/25929.
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Suggested Citation:"Chapter 12 - Other Practices." National Academies of Sciences, Engineering, and Medicine. 2020. Strategies for Work Zone Transportation Management Plans. Washington, DC: The National Academies Press. doi: 10.17226/25929.
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Suggested Citation:"Chapter 12 - Other Practices." National Academies of Sciences, Engineering, and Medicine. 2020. Strategies for Work Zone Transportation Management Plans. Washington, DC: The National Academies Press. doi: 10.17226/25929.
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Suggested Citation:"Chapter 12 - Other Practices." National Academies of Sciences, Engineering, and Medicine. 2020. Strategies for Work Zone Transportation Management Plans. Washington, DC: The National Academies Press. doi: 10.17226/25929.
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Suggested Citation:"Chapter 12 - Other Practices." National Academies of Sciences, Engineering, and Medicine. 2020. Strategies for Work Zone Transportation Management Plans. Washington, DC: The National Academies Press. doi: 10.17226/25929.
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Suggested Citation:"Chapter 12 - Other Practices." National Academies of Sciences, Engineering, and Medicine. 2020. Strategies for Work Zone Transportation Management Plans. Washington, DC: The National Academies Press. doi: 10.17226/25929.
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Suggested Citation:"Chapter 12 - Other Practices." National Academies of Sciences, Engineering, and Medicine. 2020. Strategies for Work Zone Transportation Management Plans. Washington, DC: The National Academies Press. doi: 10.17226/25929.
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194 Other Practices This section discusses decision-making tools, other practices, emerging technologies, and successful policies and procedures of selected agencies. The following practices are covered in this section: • Smart work zone implementation tools 12.1 FHWA Work Zone ITS Implementation Guide and Tool 12.2 TxDOT Go/No-Go Decision Tool 12.3 MnDOT Work Zone ITS Decision Tree • Alternate contracting decision tools 12.4 Project Delivery Selection Matrix 12.5 Procurement Procedures Selection Matrix 12.6 Project Delivery Method Selection Guidance • Work zone safety and mobility assessment at the agency and project levels 12.7 Ohio DOT Mobility and Safety Performance Measures 12.8 MDSHA Work Zone Performance Monitoring Tool 12.9 Iowa DOT Statewide Smart Work Zone Program 12.10 Safety Assessment Tool for Construction Phasing Plans • Traffic control devices 12.11 Special-color Pavement Markings 12.12 Automated Truck-Mounted Attenuator 12.13 Green Lights on TMAs • Work zone operations 12.14 Rolling Roadblock Procedure for Temporary Lane Closures 12.15 Work Zone Cell Phone Restrictions • Lane closure policies and permitting systems 12.16 Colorado Lane Closure Strategy 12.17 MnDOT Lane Closure Manual 12.18 ODOT Permitted Lane Closure Schedule 12.19 Wisconsin Web-Based Lane Closure Permitting Systems 12.20 Caltrans Lane Closure System • e-Construction and partnering 12.21 e-Construction and Partnering 12.1 FHWA Work Zone ITS Implementation Guide and Tool FHWA developed the Work Zone ITS Implementation Guide in 2014 to assist in the design and implementation of ITSs in work zones (Ullman, Schroeder, and Gopalakrishna 2014). The guide provides the key steps required to successfully implement SWZ applications, C H A P T E R 1 2

Other Practices 195 by illustrating how the systems-engineering process should be applied to determine the feasibility and design of a work zone ITS for a given application. Each key step is defined in each chapter— assessment of needs; concept of development and feasibility; detailed system planning and design; procurement; system deployment; and system operation, maintenance, and evaluation. Within the Work Zone ITS Implementation Guide, FHWA drafted general scoring criteria that agencies could use to assess the feasibility of using smart work zone technologies. 12.2 TxDOT Go/No-Go Decision Tool TxDOT has identified six SWZ systems for use in its work zones: 1. Queue detection 2. Speed monitoring 3. Construction vehicle alerts 4. Travel time systems 5. Over-height warning systems 6. Temporary incident-detection systems Because the criteria for system selections are unique to each project, TxDOT has developed an Excel-based SWZ decision tool to streamline the process of selecting an SWZ system for a project. The Go/No-Go Decision Tool scores the extent to which several criteria (e.g., work zone duration, traffic volumes, functional classification, estimated queue lengths, sight distance at back of queue, over-height vehicle/low clearance structure) are satisfied. The tool then automatically assigns the criteria scores to each of the six SWZ systems and presents a summary to help staff decide which to use. This score produces a logical basis for including any combination of SWZ systems into the project design, which effectively defines the SWZ scope. Figure 12.1 shows a snapshot of the decision tool. Appendix M provides the decision tool workbook scoring criteria. 12.3 MnDOT Work Zone ITS Decision Tree MnDOT developed a scoping decision tree to enable early and improved identification of intelligent work zone technology needs, including • Identifying resource needs, including time and resource allocations and efficiencies; • Improving project cost estimating and project scheduling; • Permitting technology interoperability; • Evaluating infrastructure readiness and compatibility; and • Deploying cost-effective solutions for future expansion and full integration of ITS. Appendix N presents the work zone scoping decision tree. 12.4 Project Delivery Selection Matrix CDOT developed a PDSM to provide a risk-based and objective selection approach to choosing from the three common project-delivery methods of DBB, D-B, and CM/GC. The PDSM provides support and justification for the choice of delivery method for a particular project. The evaluation uses project attributes, goals, and constraints to compare primary and secondary evaluation factors. Then, the selection tool uses a nonnumerical rating system for each evaluation factor, so that the cumulatively highest ranked method becomes the optimal delivery method. Figure 12.2 shows the PDSM process flowchart. Appendix J1 includes the full PDSM tool and provides an example of a PDSM decision.

196 Strategies for Work Zone Transportation Management Plans Scoring Factors Scoring Range Criteria Score Impact from local traffic generators Significant-local facilities are large enough to have official destination signs on the Interstate highway such as conference centers, sports arenas etc., so they produce large surges in traffic before/after large events (20 points) Moderate-Local businesses or public facilities generate traffic volumes that routinely backup the on/off ramps such as morning and evening rush hours (10 points) Minimal-Any circumstance that causes occasional backups on the on/off ramps such as congested local arterials or rail crossings (5 points) None (0 points) Estimated Queue Length (Calculated, or see Max Queue Length tab for rough estimate) > 7 miles (130 points) 3.5 to 7 miles (110 points) 0 to 3.5 miles (85 points) None (0 points) Sight Distance at back of Queue Sight distance issues exist where the back of queue will likely occur. (30 points) Not applicable (0 points) Existing traffic issues Higher than normal crash rates, gridlock or frequent exit ramp backups (30 points) Not applicable (0 points) Availability of Alternate routes Convenient alternate routes with capacity are available. (3 points) No alternate routes available (0 points) Merging conflict or hazards on the approach to work zone External merging conflicts or hazards on the approach to or within the work zone. (15 points) Not applicable (0 points) Complex traffic control layout Multiple crossovers, sharp curves or lane splits (3 points) Not applicable (0 points) Adjacent/consecutive project There are adjacent active projects effectively creating a mega-project that totals... longer than 10 miles or longer than 2 years (3 points) between 5 to 10 miles or between 1 and 2 years (2 points) between 2 to 5 miles or between 6 months to 1 year (1 point) less than 2 miles or less than 6 months (0 points) Scattered/short term project The project includes multiple short term lane restricting activities that are scattered across the state. (ex. bridge painting) (3 points) Not applicable (0 points) Extreme weather condition Work zone has a known history of sudden extreme weather condition, sandstorm, etc. Or project duration covers several harsh weather season. (3 points) Not applicable (0 points) Connected vehicle >5% (3 points) <5% (0 points) Existing ITS Systems Project falls inside an existing Advanced Traffic Management System? The TMC has the intent to incorporate the travel time and delay estimating system into the TMC operations? The TMC can remotely control their existing advance traveler information systems? (Each question worth 1 point) Heavy vehicles >12% (3 points) >9% (2 points) >6% (1 point) <=6% (0 points) 0 0 Raw Score Normalized Score (0 to 100) Figure 12.1. TxDOT Go/No-Go Decision Tool scoring criteria (Credit: TxDOT).

Other Practices 197 YESNO NO YES List Project Attributes Review Project Goals Identify Project Constraints Assess Primary Evaluation Factors: 1) Delivery Schedule 2) Project Complexity & Innovation 3) Level of Design 4) Cost Does primary factors assessment indicate an optimal method? 5) Perform initial risk assessment for optimal method Is one method the most appropriate in managing risk? 5) Perform initial risk assessment for all possible methods Pass/Fail assessment of secondary factors for optimal method: 6) Staff Experience/Availability 7) Level of Oversight & Control 8) Competition & Contractor Exp. Perform full assessment of secondary factors for all methods Delivery Method Selected Does optimal method pass for all secondary factors? YES NO Project Delivery Method Selection St ag e 1 St ag e 2 St ag e 3 Figure 12.2. Project delivery selection matrix flowchart (Credit: University of Colorado).

198 Strategies for Work Zone Transportation Management Plans 12.5 Procurement Procedures Selection Matrix The CDOT procurement decision-support tool, called the Procurement Procedures Selec- tion Matrix (PPSM), provides a risk-based and objective selection approach to choosing a procurement procedure from the three common procurement criteria of low bid, best value, and best qualified. The PPSM then provides support and justification for the procedure chosen. The selection process, similar to the process used for selecting a delivery method, uses specific project attributes, goals, and constraints to evaluate factors critical to the decision. The evalua- tion factors use a qualitative rating system, and the overall highest-ranked procedure becomes the most appropriate procurement procedure. Figure 12.3 shows the PPSM process flowchart. Appendix J2 includes the full PDSM tool and provides an example of a PDSM decision. 12.6 Project Delivery Method Selection Guidance Using CDOT’s PDSM as a foundation, WSDOT developed the Project Delivery Method Selection Guidance (PDMSG). The previous selection process automatically assumed DBB as the project-delivery method (PDM) unless approval to use D-B or CM/GC as the contracting Figure 12.3. Procurement procedures selection matrix flowchart (Credit: University of Colorado).

Other Practices 199 method was pursued. The PDMSG provides progressive evaluation tools to determine the optimal PDM, with each tool scalable to the appropriate level of effort based on the type and size of the project. The original policy was that every project was required to be evaluated under PDMSG. WSDOT’s direction now is that projects less than $2 million and preservation projects less than $10 million are programmatically excepted from PDMSG. All projects are evaluated in two steps: Step 1. Before region program management offices approve the project profile, the probable PDM is established through collaboration with region subject experts and is documented in the Capital Program Management System. Step 2. Once the project profile is approved and the design stage is about 10 percent to 30 percent complete, the final PDM is determined, a work order is set up for the project, and the project is assigned to a region project engineer’s office. A selection checklist (Appendix K1) is used during the final PDM to quickly identify projects that have an obvious optimal PDM. A selection matrix (Appendix K2), if needed as a second step, is used for more complex projects to determine the final PDM. A workshop is required for projects that cost $100 million or more to determine the final PDM. 12.7 Ohio DOT Mobility and Safety Performance Measures 12.7.1 District Work Zone Traffic Manager Notification Plan for Significant Impacts (by TMC) The ODOT statewide TMC sends a courtesy notification to the ODOT district work zone traffic manager (DWZTM; one designated per district) when a significant (>0.75 mi) queue results from work zone operations that were not previously planned (and approved). Upon notification, the DWZTM verifies the field conditions to determine if queuing is the result of work zone operations or some other incident and addresses the concern as appropriate. This procedure helps ODOT monitor and mitigate unexpected queuing. Figure 12.4 is an example of a notification that would be sent when an unexpected significant impact was observed as a result of a work zone operation. The notification is limited to what the TMC operators are monitoring and does not include all of the projects and roadways. 12.7.2 Work Zone Mobility Report (a.k.a. volcanogram) The ODOT volcanogram report includes graphs representing the number of hours in which traffic speeds dropped below 35 mph in or on either side of a work zone during each month. There are also monthly views to compare different months and to compare the same month across different years for the 2 years before construction began. The volcanogram indicates traffic speeds before and after work zones are in place and also gives a general idea of the delay pattern. If there is a sudden change in one month, the work zone traffic managers can determine if there is any issue or shift in configuration. There are also efforts to extend the reports a few miles on either side of the work zone to provide an overall review by including work zone effects propagated upstream and downstream, outside the normal work zone length. Volcanogram reports are run for a select number of projects each year. Figure 12.5 provides an example. The black vertical bars represent the limits of the work zone, and the report can show more than one project if they are closely located. For comparison, the chart contains historic lines representing the same number of hours to that point in the 2 years before construction (each month is a different band or layer in the graph, and the historic lines also represent the

200 Strategies for Work Zone Transportation Management Plans Figure 12.4. Snapshot of ODOT queue notification (Credit: ODOT). Figure 12.5. ODOT work zone mobility report, a.k.a. volcanogram (Credit: ODOT).

Other Practices 201 total number of hours for same month for the respective historic year). ODOT also looks for irregularities in the bands or an unusually high number of hours under 35 mph in reference to the trend for the corridor. As the scale adjusts for each zone based on the overall numbers, users need to reference the x-axis scale to keep the number in perspective, rather than just going by the visual effect of the spikes. Volcanogram reports are shared with the DWZTMs, who in turn share them with the project engineers. Any irregularities found and the resulting information received is shared with the Project Impact Advisory Council at its monthly meeting. 12.7.3 Work Zone Crash Summary (near real time) Crash summaries are run each month on the same select projects that run volcanograms. Crash data are extracted electronically from the law enforcement agency. The data display the number of crashes throughout the corridor as well as by month and the historic maximum. The 3-year average before construction is also shown for reference. DWZTMs receive work zone crash summaries and are encouraged to share them with project engineers. The DOT checks for irregularities and discusses with the districts to determine a reason for the irregularity and any improvements that can be made. Figure 12.6 is an example of a crash report summary. 12.7.4 Work Zone Crash Modification Factors Report ODOT also runs a CMF report monthly on many of the same. These reports compare the number of crashes in a specific work zone with the expected crashes based on a CMF for work zone presence. The CMFs used are from NCHRP Research Report 869 (Ullman et al. 2018) and are for work zones with no lane closure where worker presence is unknown. Figure 12.7 shows the formulas and a snippet from the report. 12.8 MDSHA Work Zone Performance Monitoring Tool In 2015, MDSHA developed the web-based Work Zone Performance Monitoring (WZPM) tool to assist in compliance with requirements in the Final Rule on Work Zone Safety and Mobility. The WZPM tool uses agency-provided construction and incident data feeds merged with INRIX probe vehicle data to calculate real-time mobility and safety information within and around a work zone. The WZPM tool uses probe vehicle data to show real-time flow information within and around a work zone. Users are able to view the current flow conditions, including speed, travel time, and queue length, through the work zone or within a user-selected number of miles upstream and downstream from the work zone. The real-time flow information is plotted and compared with historical conditions to identify slowdowns, delays, and poor mobility in general. In addition to flow information, the WZPM tool calculates user delay cost associated with each work zone to communicate the cost of time and fuel consumption, as well as the emissions drivers experience because of the work zone (Figure 12.8). The WZPM tool pulls incident information from MDSHA’s CHART real-time operations system to show nearby incidents and lane closures that may affect or may be affected by the work zone. The tool maintains a historical count of nearby incidents to provide additional information related to frequency of incidents and their relationship to the work zone. Live CHART CCTV feeds are also available to allow users to view the traffic conditions.

Figure 12.6. ODOT work zone crash summaries (Credit: ODOT). Figure 12.7. ODOT WZCMF formulas and report (Credit: ODOT).

Other Practices 203 Figure 12.8. Snapshot of Maryland’s Work Zone Performance Monitoring Tool (Credit: MDSHA).

204 Strategies for Work Zone Transportation Management Plans 12.9 Iowa DOT Statewide Smart Work Zone Program In 2014, the Iowa DOT initiated a new effort to identify key work zones across the state as traffic-critical projects (https://sites.google.com/site/iowatcp/home). The Traffic Critical Projects program identifies key construction projects across the state that may cause significant safety or mobility issues to the traveling public. Using various mitigation methods, the program works to reduce or eliminate any potential safety or mobility concerns. A snapshot of the Traffic Critical Projects web page is shown in Figure 12.9. Since its inception in 2014, the Traffic Critical Projects program has grown from 20 projects with 14 SWZ systems to 78 traffic-critical projects with 42 SWZ systems in 2017. To best facilitate SWZ deployments on selected traffic-critical projects, Iowa DOT determined that a stand-alone, qualification-based procurement contract for an SWZ device vendor would provide the greatest benefit at lowest cost to meet Traffic Critical Projects program goals. Iowa DOT used a support consultant to help develop an RFP to select vendors to provide SWZ equipment throughout the state. A stand-alone SWZ vendor contract, separate from construc- tion contracts, was employed to ensure the vendor had the required technical expertise to allow quicker and easier response to system operations and for flexibility to add or remove SWZs to projects not initially identified on the original Traffic Critical Projects list. For system deployment, planned SWZ device locations are first verified and marked in the field for optimal visibility and to maintain state and federal sign spacing recommendations (Figure 12.10). The SWZ vendor then brings the equipment on site, placing devices at the marked locations in the corridor, and provides device details for software integration. Software integration involves entering the SWZ equipment into the traffic management software and incorporating alert-processing logic required for EQWS. This also included adding the SWZ PCMSs and cameras to the public 511 website and mobile application. The SWZ tools being used include traffic sensors and cameras that can monitor the areas 24/7, sending data on traffic speeds, queue length, and images to the local TMC. Operators in the TMC can then communicate through message signs along the road, the 511 system, and Twitter and Facebook to alert the public to issues that might affect them. Live video from the cameras Figure 12.9. Snapshot of Iowa traffic critical projects program website monitoring (Credit: Iowa DOT).

Other Practices 205 can also be viewed at http://www.511ia.org/. In addition to the SWZ tools alerting the TMC, engineers and inspectors working on specific projects will automatically receive text messages when slowdowns of more than 5 minutes happen in a work zone equipped with speed sensors. By using real-time video feeds, receiving notifications of traffic backups or other disruptions in the flow of traffic from the queue detection units, or observing speed trends from INRIX and Google data, Iowa DOT is able to manage traffic in the work zone effectively. The portable and static message signs are used to manage queue backups, provide advance warning of delays, or move traffic to preplanned routes or detours. Iowa DOT’s statewide approach to intelligent work zones is unique. Many states deploy various intelligent work zone technologies on a project-by-project basis, but their systems may not be compatible across projects and their TMCs may not be able to monitor them. In Iowa’s case, the TMC receives alerts when queues are detected and uses the SWZ cameras and message signs just like its permanent cameras and signs. SWZ system evaluation and performance monitoring is made possible through a collaboration with Iowa State University’s Center for Transportation Research and Education. In 2017, the Center used several layers of performance measures and data from within and just beyond the work areas to evaluate each project. The performance-monitoring tools developed allow users to view, in real time, the effects of work zones on traffic. The Center’s web-based interactive tool has various modules, including an overview map, weekly performance, daily performance, speed heat maps, sensor performance, and hourly volumes. Implementation of this program has had significant effects on how the Iowa DOT operates and maintains construction and maintenance work zones: • Performance measures. Performance-monitoring tools were developed to view the effects of work zone projects on traffic and to monitor the traffic-sensor operating status. The data Figure 12.10. Iowa’s Traffic Critical Projects and intelligent work zone device location map (Credit: Iowa DOT).

206 Strategies for Work Zone Transportation Management Plans collected by cameras, sensors, and message signs are connected to a web-based performance- monitoring tool, which is updated every night to add information about the previous day to the view. All historical data are retained from the database, so information from any time interval can be queried at any point. Traffic sensors have been the primary source of data for performance monitoring since the Traffic Critical Projects program was established. Sensors provide high-granularity data, which are beneficial when monitoring performance but could be highly variable based on the make or model of the sensors. During the 2017 construction season, the Iowa State University Institute of Transporta- tion (InTrans) significantly improved performance-monitoring results by using machine learning to eliminate common false traffic events, by using a fixed 45 mph threshold. Machine learning better identifies traffic events and has significantly improved the accuracy of the performance measures and decreased the number of false events detected by the previous systems. Recently, InTrans expanded the use of INRIX data to monitor projects and road- ways where sensors are not deployed. INRIX probe data do not include volume, so the performance measures differ slightly from what is available using permanent or portable sensors. The amount of INRIX data is highly variable based on the type of roadway. InTrans receives a weekly snapshot of crash data from Iowa DOT, which provides the ability to perform further crash analysis regularly. • Text alerting. InTrans developed a work zone text messaging alert system during the 2017 construction season. Machine learning was used to identify slow and stopped conditions within the work zone, which was then used to develop an algorithm to send text alerts of slowdowns in work zones across the state. A feed was developed to summarize this information for each work zone and is used in the TMC operations dashboard, as well as for text alerting to DOT staff. • Work zone capacity. At the time this guidebook was written, InTrans was working with Iowa DOT to determine the capacity of different work zone configurations, including a capacity comparison for bridge-related work using a single lane versus two narrow lanes. Additionally, InTrans is looking at the effects towing and extra enforcement have on capacity. • Lane closure planning tool. The lane closure planning tool provides convenient access to traffic data, which can be used to determine when a lane can safely be closed. The tool uses data from ITS sensors to update its database every month, which includes the hourly volume by month, day of week, and time of day. Hourly volumes are currently being expanded to include the average, minimum, maximum, and 25th and 75th percentiles. In addition to raw hourly volume, automobile-equivalent hourly volume is also calculated. • Open data service. InTrans has developed an open data service intended to provide high- quality, near real-time data feeds for any public or private entity. Data feeds and services support both agency and external users over a wide range of use categories. The sources are varied and can include operation, roadway, weather, maintenance, and safety data. Several InTrans initiatives, including text alerting, the TMC operations dashboard, and the lane closure planning tool, use the open data service for their databases. This data service integrates multiple data sources available to the DOT. 12.10 Safety Assessment Tool for Construction Phasing Plans The Highway Safety Manual (HSM) (AASHTO 2010) provides limited guidance for work zone safety evaluation. It only gives two CMFs to calculate the effect of an increase or a decrease of freeway work zone length and duration on the crash count.

Other Practices 207 A study (Brown et al. 2016) conducted for FHWA by the University of Missouri–Columbia addressed this gap in knowledge by developing a spreadsheet-based safety assessment tool for freeways, expressways, rural two-lane highways, urban multilane highways, arterials, signalized intersections, un-signalized intersections, and ramps. Using data from Missouri work zones, the study developed 20 crash-prediction models. The tool predicts crashes by severity and crash costs for each work zone alternative based on input data provided by the user. All models were programmed in a user-friendly spreadsheet tool for practitioners. An illustrative example is presented to show how this software can be used for assessing the safety of different work zone plans. Figure 12.11 and Figure 12.12 show the software graphical user interface and an example of output, respectively. 12.11 Special-Color Pavement Markings Roadway lanes are often repositioned to accommodate highway work operations; as a result, pavement markings need to be altered. Although there are various methods for removing or obscuring pavement markings, “ghost” markings often remain at the locations of the old lane lines. These ghost markings can be conspicuous under certain lighting conditions, creating the potential for road-user confusion. The Canadian province of Ontario and several European countries routinely use a special marking color (orange or yellow) to increase the salience of temporary lane lines. Special-color markings have also been used experimentally in Australia; New Zealand; Quebec City, Canada; and the United States. WisDOT had difficult conditions at a high-volume freeway-to-freeway interchange project (Zoo Interchange) in winter, as salt residue on the roadway surface obscured the traditional white lane markings. To provide more clearly defined lanes in the work zone, WisDOT sought and was granted experimental permission by FHWA in 2014 to use orange paint (Figure 12.13). Figure 12.11. User input window of the safety assessment tool (Credit: University of Missouri).

208 Strategies for Work Zone Transportation Management Plans Figure 12.12. Sample output of the safety assessment tool (Credit: University of Missouri). Figure 12.13. WisDOT use of orange pavement markings (Credit: John Shaw/University of Wisconsin–Madison). Orange reflective epoxy paint has been used in Canada, New Zealand, and Europe but not previously in the United States. However, a direct assessment of the Zoo Interchange site was difficult because of the fast- paced construction with frequent lane and alignment changes, high traffic volumes, and recurring congestion even before the project began. These complexities made it challenging to separate the driver behavior and traffic operations effects of the orange markings from those attributable to other site conditions and traffic management techniques.

Other Practices 209 To assess the driver behavior aspects of orange markings in a simpler environment, WisDOT conducted a matched-pair with and without study on two bridge re-decking projects on I-94 near Oconomowoc (Shaw, Chitturi, and Noyce 2017; Shaw et al. 2018). No significant differences were found between the distributions of lane position and speed data for the test and control sites. However, a driver survey indicated that the orange markings were more visible and easier to see. Based on the field data, driver surveys, and interviews of field engineers, there was no evidence that drivers miscomprehended the orange markings. The study concluded that “perhaps the most pragmatic approach is to reserve orange as an emphasis color for specific work zone locations that require difficult driving maneuvers. This approach is similar to the British practice of parsimoniously using special marking colors to provide emphasis in problematic areas, and would help reduce the potential for drivers to become desensitized to the special color.” 12.12 Automated Truck-Mounted Attenuator One type of positive protection developed and often used in work zones is the TMA. The TMA is positioned as a shadow vehicle, relative to the workers, work vehicles, or the immediate workspace. TMAs save lives and prevent injuries for both motorists and maintenance workers, but they put the TMA driver at risk of injury when the attenuator is hit. Recent technology has allowed an option to remove the driver from the buffer vehicle designed to be struck by errant vehicles. The autonomous truck-mounted attenuator (ATMA), also known as the autonomous impact protection vehicle, consists of two vehicles, a leader and a follower. The leader vehicle is human driven and is equipped with an onboard computer, digital compass, transceiver, and GPS receiver. The lead vehicle wirelessly transmits high-accuracy data on its position, speed, and heading. The ATMA receives this transmission and copies the lead vehicle’s movements using steering, throttle, and brake actuators. ATMAs can be retrofitted to existing TMAs. Figure 12.14 shows the leader and follower vehicles. At the time this guidebook was written, ATMAs had been tested and were already in use in a few states, but only in a limited capacity as part of pilot programs, including the following: • Act 117, passed in October 2018, allows for PennDOT and the Pennsylvania Turnpike Commission to implement highly automated work zone vehicles in active work zones. • In August 2017, CDOT became the first transportation department in the United States to purchase and demonstrate an ATMA when a CDOT road-striping crew used the ATMA Figure 12.14. Autonomous TMA (Credit: Royal Truck and Equipment, Inc.).

210 Strategies for Work Zone Transportation Management Plans near Fort Collins. Colorado has also used its ATMA in rural areas away from heavy or mixed traffic. • FDOT tested an ATMA in 2015. ATMA technology is still in the late stages of development and there are several challenges to be addressed: • The following vehicle copies the movements of the lead vehicle exactly; if the lead vehicle encounters an obstacle and has to change lanes, the ATMA won’t change lanes until it also encounters the obstacle. This leaves the lead vehicle without protection until the ATMA also changes lanes. • The lead and following vehicles sometimes lose communication when passing under overpasses or through tunnels. 12.13 Green Lights on TMAs MoDOT (Brown et al. 2018) tested the use of green lights on TMAs to improve work zone visibility. This was the first quantitative study of green lights on TMAs in the United States, and MoDOT used simulator and field studies to test four different configurations. The simulator testing phase examined amber/white (MoDOT typical), green only (MoDOT preferred), green/amber (MoDOT alternative), and green/white (design alternative) configura- tions. The field test evaluated the amber/white and green-only configurations (Figure 12.15). Video data were collected for 2 days in a mobile work zone on US 50 in the Kansas City area. The mobile work zone consisted of a green-only rear advance TMA and an amber/white shoulder TMA for the first day and two amber/white TMAs for the second day. During daytime, the leading vehicle passing speed for amber/white TMAs was slightly higher (64.5 mph) than for the green-only TMA (62.5 mph). During nighttime, vehicle passing speed for the green-only TMA was slightly lower (52.1 mph) compared with the amber/white TMAs (52.9 mph). The authors cautioned that driver behavior could have been influenced by the novelty effect of green-light TMAs and that a longer-duration study is necessary to examine the novelty effect. The results did not point in a single direction for both the simulator and field tests, and all four configurations appeared to be viable. 12.14 Rolling Roadblock Procedure for Temporary Lane Closures According to FHWA, a rolling roadblock, also known as a temporary road closure, rolling block, pacing operation, or traffic pacing, is a common highway traffic control technique used to temporarily slow or stop traffic upstream of construction, maintenance, and utility work activities requiring a short-term full closure of the roadway (FHWA, n.d.). Rolling roadblocks allow for faster completion of roadwork activities by allowing workers full access on and above a roadway, and the opportunity for a safe environment by completely removing vehicles that would normally be close to workers. Policies and procedures governing the use of rolling roadblocks for highway work activities vary by state. Additional resources are available to transportation agencies for improving rolling roadblock practices. Among these resources is Guidelines on Rolling Roadblocks for Work Zone Applications, developed by the American Traffic Safety Services Association. This guide establishes best practices in the use of rolling roadblocks and provides valuable information on

Other Practices 211 planning and coordinating a rolling roadblock, executing a rolling roadblock, and developing a rolling roadblock planning checklist. The Connecticut DOT allows rolling roadblocks during the installation of temporary lane closures on limited-access highways. Rolling roadblocks are allowed for installing and removing lead signs and lane tapers only, for a maximum duration of 15 minutes. 12.15 Work Zone Cell Phone Restrictions As part of ongoing efforts to reduce distracted driving and increase safety for motorists and workers in work zones, Wisconsin passed legislation making it illegal to talk on a handheld mobile device while driving in a Wisconsin roadwork zone. The 2015 Wisconsin Act 308 went Figure 12.15. Simulator testing TMA configurations (Credit: University of Missouri).

212 Strategies for Work Zone Transportation Management Plans into effect on October 1, 2016, and drivers caught in violation face fines of up to $40 on first offense and up to $100 for subsequent offenses. Appendix L provides bill text (2015 Assembly Bill 198). The sign associated with this law is shown in Figure 12.16. Hands-free and Bluetooth devices are granted exemptions and remain legal to use. The law also grants an exception for drivers to use a handheld mobile device if dialing 911. Wisconsin continues to enforce zero tolerance for texting while driving through work zones. Wisconsin does not prohibit drivers from using handheld cell phones while driving, outside work zones. However, Wisconsin law forbids driving any motor vehicle while composing or sending a text message or an e-mail message (primary law). 12.16 Colorado Lane Closure Strategy The CDOT developed Lane Closure Strategy (LCSY) for each of its five regions to establish uniform criteria and authoritative guidance for scheduling lane closures. Each region’s policy is unique—enabling CDOT to tailor its lane closure policies to a vast state that encompasses both rural mountainous areas and large urban areas. The LCSY was formulated to strike an appropriate balance between delays to the traveling public in the work zone and the cost of construction and maintenance. The LCSY is applicable to single-lane closures (and multilane closures on five-or-more-lane roadways) related to construction and maintenance activities on roads CDOT controls. It is based on extensive data analyses and estimates of delays expected during lane closures. The LCSY addresses weekday and weekend traffic demand and considers temporal variations in traffic volume occurring over a typical 24-hour period. The LCSY also accounts for seasonal variations in traffic volumes, where appropriate. In the past, lane closure decisions were primarily based on field observations, previous experience, and engineering judgment. LCSYs are recalibrated on a 3- to 5-year rotation to reflect changes in traffic volumes and available capacity (Region 1, 5th edition, was published in 2019; Region 2, 2nd edition, in 2013; Region 3, 3rd edition, in 2017; Region 4, 3rd edition, in 2017; and Region 5, 1st edition, in 2008). LCSYs provide several types of information related to closures in each region, including the following: • General background information on traffic conditions in the area. • Allowable lane closure hours for all state highways in a tabulated form. The tables provide specific times at which closures will be allowed for each highway section. Sections are divided where lane geometry changes or daily traffic volumes change significantly. • Procedures for implementing a lane closure for access permit and maintenance work. • Procedures for implementing a lane closure for CDOT design projects. Figure 12.16. Wisconsin work zone cell phone restriction sign (Credit: WisDOT).

Other Practices 213 • Procedures for changing the closure hours during the construction and variance request process. • Flowcharts (Figure 12.17) to identify the allowable lane closure hours for a specific state highway under the following conditions: – All seasons. – Number of lanes closed—one, two, or three. – Freeway ramp-closure schedules. – I-70 mountain corridor closure schedules. Using the information presented in the LCSY has improved the quality of lane closure deci- sions, simplified the decision process for the end user, and reduced the uncertainty associated with handling traffic during construction. 12.17 MnDOT Lane Closure Manual MnDOT developed a lane closure manual to use when planning and scheduling lane and shoulder closures on MnDOT-owned and -operated freeways and expressways in the Metro District, District 6, and District 3. The lane closure manual determines the appropriate Figure 12.17. CDOT lane closure scheduling decision tree (Credit: CDOT).

214 Strategies for Work Zone Transportation Management Plans time of day for planned lane closures based on the number of available lanes and traffic- count data. The purpose of the lane closure manual is to provide information useful for advance planning of lane closures that will minimize traffic impacts and motorist delays while promoting safety for work crews and the traveling public. Lane closures allowed by this manual are typically short term (12 hours or less) and do not involve a traffic detour or diversion. Traffic-flow volumes from regional TMC detectors and tube counters are collected, analyzed, and formatted to display allowable lane closure figures based on roadway location and time of day. The manual is divided into sections by roadway, and each roadway is divided into segments. Segments are generally determined by the number of continuous lanes available along a highway corridor. The index maps illustrate where each roadway is broken down into numbered segments (Figure 12.18). The numbered segment directs the user to the correct page of the manual that provides tabulated traffic data (Figure 12.19). MnDOT uses a system of shading to display the number of lanes that can be closed for each hour of the day. The allowable lane closure figures given in the lane closure manual have been smoothed to remove some of the seasonal data fluctuations. 12.18 ODOT Permitted Lane Closure Schedule The ODOT lane closure policy is described within the Policy for Traffic Management in Work Zones (Standard Procedure No: 123-001). The policy was developed to systematically determine the effects created by work zones and will eliminate, minimize, or mitigate these effects to the greatest extent practical. ODOT lists the process of determining lane closure times on its permitted lane closure schedule website. The permitted lane closure schedule is a web-based searchable database tool that provides a quick and efficient method for identifying which hours of the day lane closures should not result in violations of the allowable queue length threshold. Figure 12.18. MnDOT lane closure manual roadway segments (Credit: MnDOT).

Other Practices 215 Figure 12.19. MnDOT lane closure manual showing allowable lane closures (Credit: MnDOT).

216 Strategies for Work Zone Transportation Management Plans The user searching for permitted lane closure times inputs the following information: year of the last ADT count, district number, county, route, and the section of that route. The search yields a table—similar to the screenshot in Figure 12.20—showing the permitted lane closure times. The times of the day that lane closures are not permitted are indicated by the different shaded hours for each day of the week, for construction and nonconstruction seasons. The table also includes the lane capacity used when determining if a lane closure is permitted. These capacities vary from facility to facility. The permitted lane closure schedule application, based on the Internet, is a convenient way to find lane closure times for certain facilities. The lane closure capacities are adjusted based on conditions of the facility, so a better approximation of the lane capacity is applied. 12.19 Wisconsin Web-Based Lane Closure Permitting Systems The Wisconsin Lane Closure System (LCS) is a web-based system for tracking closures and restrictions on Wisconsin Interstate, U.S., and state highways. The purpose of the LCS is to Figure 12.20. ODOT permitted lane closure schedule (Credit: ODOT).

Other Practices 217 • Provide a standard interface for lane closure operations, closure tracking, and data retrieval for WisDOT regional offices statewide; • Facilitate data sharing with WisDOT applications that require lane closure data from 511 traveler information, the statewide TOC, inconvenience map production, and oversize/ overweight permitting; • Improve the completeness, reliability, and timeliness of lane closure data on state highways; • Archive LCS data in the WisTransPortal system for future analysis and integration with other WisDOT/UW-TOPS Lab traffic-engineering applications and research; and • Integrate historical traffic-flow data and capacity information to calculate available closure thresholds. The LCS is the single source of Wisconsin Interstate, U.S., and state highway lane and ramp- closure information. Closure and restriction information is entered for • All let projects or design projects with impacts to an Interstate, U.S., or State highway; • Any planned maintenance or permit/utility restrictions of closures on Interstates, U.S., and state highways; • Major special events; and • Any unplanned emergency lane closures. The LCS shares data with several internal and external mediums: the Wisconsin 511 system, the WisDOT website, statewide TOC, daily/weekly e-mail reports, and third-party media (vehicle navigation systems, phone/tablet apps, websites, social media, and news reports). Closure information can be entered into the LCS by any system user. WisDOT staff can enter the information or request that a consultant, contractor, or county enter the information. However, closures need to be entered into the LCS in compliance with the minimum advance notification time frames shown in Figure 12.21. Depending on the type of closure and the user entering the closure, the closure will be either automatically accepted or sent through the acceptance process. If a user has acceptance authority, the system allows, but does not require, the user to immediately accept the entered closure information into the system. Once accepted, the information is live and therefore published as an active closure. A user may only enter and act on a closure located within the same region as the user’s region. The region options in LCS include SE (Southeast), SW (Southwest), NE (Northeast), NC (North Central), NW (Northwest), and ALL (All Regions). Figure 12.21. WisDOT lane closure advance notification times (Credit: WisDOT).

218 Strategies for Work Zone Transportation Management Plans Operational since April 2008, the LCS facilitates work zone acceptance and monitoring at WisDOT statewide TOC and regional transportation offices and provides real-time lane closure information to the Wisconsin 511 traveler information system. 12.20 Caltrans Lane Closure System On January 15, 2016, Caltrans revised the 2015 Standard Specifications, Section 12-4.02C(2), Lane Closure System, to implement the use of the LCS mobile web page to report closure status. The LCS was developed to reduce the steps needed to cancel or start closures and to allow contractors to interface directly with the LCS, helping expedite and improve the accuracy of lane closure status. Contractors are required to request closures using the Caltrans LCS and status closures using the Lane Closure System mobile web page. Every 5 minutes LCS reports all approved closures planned for the next 7 days, plus all current lane, ramp, and road closures caused by maintenance, construction, special events, and so on. The LCS disseminates construction information to the Caltrans online tools QuickMap, Commercial Wholesale Web Portal, and Performance Measurement System and the Caltrans Highway Information Network hotline. When the contractor changes the status of a closure, the LCS sends an e-mail notification to the resident engineer and designated inspectors. 12.21 e-Construction and Partnering Through Round 4 of the EDC, the FHWA has promoted e-construction and construction partnering as practices that can be used in concert to help deliver transportation improvements smarter and faster. e-Construction is the creation, review, approval, distribution, and storage of highway construction documents in a paperless environment. These paperless processes include electronic submission of all documentation by all stakeholders, electronic document routing and approval (e-signature and workflows), and real-time management of all documents in a secure digital environment accessible to all stakeholders through mobile devices and web- based platforms. e-Construction aims to employ established technologies that are readily available to the transportation community, such as digital electronic signatures, electronic communication, secure file sharing, version control, mobile devices, and web-hosted data archival and retrieval systems to improve construction documentation management. Many state DOTs and industry practitioners are already using or testing some aspects of e-construction. Some are even in the process of mainstreaming many e-construction system practices. MDOT has applied e-Construction routinely to DBB projects, while the Minnesota, Florida, Utah, Texas, Pennsylvania, and North Carolina DOTs have applied this technology to D-B projects. The Wisconsin and Iowa DOTs have applied e-construction to DBB projects. MDOT, a leader in e-construction, estimates that the agency saves approximately $12 million in added efficiencies and 6,000,000 pieces of paper annually by using electronic document storage for its $1 billion construction program while reducing its average contract modifica- tion processing time from 30 days to three days (https://www.fhwa.dot.gov/innovation/everyday counts/edc-3/econstruction.cfm).

Other Practices 219 The e-construction system has the potential to increase the quality, efficiency, environmental sustainability, and productivity of the construction industry at large, while saving printing costs, time, postage, and document storage and adding communication efficiencies. Construction partnering is a project management practice whereby transportation agen- cies, contractors, and other stakeholders create a team relationship of mutual trust and improved communications. Partnering builds relationships and connections among stake- holders to improve outcomes and successful completion of quality projects that are built on time and within budget, focused on safety, and profitable for contractors. Additional information, webinars, and peer exchange reports relating to e-construction and construction partnering can be found at https://www.fhwa.dot.gov/construction/econstruction/ and at https://www.fhwa.dot.gov/construction/partnering/, respectively. 12.22 Resources and References ATSSA. Guidelines on Rolling Roadblocks for Work Zone Applications, FHWA, U.S. DOT, July 2013. https://www. workzonesafety.org/training-resources/fhwa_wz_grant/atssa_rolling_roadblocks/. Brown, H., C. C. Sun, P. Edara, and R. Rahmani. Safety Assessment Tool for Construction Zone Work Phasing Plans, InTrans Project Report 203, 2016. Brown, H., C. Sun, P. Edara, S. Zhang, and Z. Qing. Evaluation of Green Lights on TMAs, Missouri Department of Transportation, MoDOT project #TR201722, May 2018. FHWA. Safely Implementing Rolling Roadblocks for Short-Term Highway Construction, Maintenance, and Utility Work Zones, Work Zone Management Program, FHWA-HOP-19-031, FHWA, U.S. DOT, n.d., https://ops.fhwa.dot.gov/publications/fhwahop19031/index.htm, accessed September 5, 2019. Highway Safety Manual, AASHTO, Washington, D.C., 2010. [HSM] Shaw, J. W., M. V. Chitturi, and D. A. Noyce. Special-Color Pavement Marking for Highway Work Zones: Literature Review of International Practices. Transportation Research Record: Journal of the Transportation Research Board, No. 2617, 2017, pp. 78–86. Shaw, J. W., M. V. Chitturi, K. R. Santiago-Chaparro, L. Qin, A. Bill, and D. A. Noyce. Orange Work Zone Pavement Marking Midwest Field Test, Smart Work Zone Deployment Initiative, April 2018. Ullman, G., J. Schroeder, and D. Gopalakrishna. Use of Technology and Data for Effective Work Zone Management: Work Zone ITS Implementation Guide, FHWA-HOP-14-008, FHWA, U.S. DOT, January 2014. Ullman, G. L., M. Pratt, M. D. Fontaine, R. J. Porter, and J. Medina. NCHRP Research Report 869: Estimating the Safety Effects of Work Zone Characteristics and Countermeasures—A Guidebook. Transportation Research Board, Washington, D.C., 2018. http://dx.doi.org/10.17226/25007.

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One of the ways a state department of transportation or other transportation agency can address work zone safety and other impacts is to develop and implement a transportation management plan (TMP).

The TRB National Cooperative Highway Research Program's NCHRP Research Report 945: Strategies for Work Zone Transportation Management Plans provides a practitioner-ready guidebook on how to select and implement strategies that improve safety and traffic operations in roadway construction work zones.

Supplemental materials to the report include NCHRP Web-Only Document 276: Evaluating Strategies for Work Zone Transportation Management Plans; fact sheets on ramp meters, reversible lanes, and truck restrictions; and guidebook appendices.

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