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C H A P T E R 4 Case Studies: Work Zone Management Work zones in the United States account for approximately mobility requirements provided by FHWA, 23 CFR Part 630, 10% of congestion, according to research from the FHWA Subpart J. (1). Work zones are defined as any construction activities that In preparation for this case study, a discussion was held with result in physical changes to the highway environment, such Joseph Ishak, PE, Central Work Zone Traffic Control (WZTC) as reductions in the number or width of travel lanes, lane Section engineer, and Jennifer Portanova, PE, project design shifts, lane diversions, and temporary road closures. Work engineer, both with NCDOT. The following information rep- zones often reduce capacity and may experience higher crash resents their knowledge based on specific project experience. rates than other segments of freeways, thereby contributing to a decrease in reliability. Furthermore, longer-term closures Description for major construction projects often have shifting impacts as traffic control strategies are modified to respond to changing This case study was selected based on the proactive approach schedules or unforeseen issues in the field. to managing the impacts of the project work zone and the con- This section presents case studies that examine the processes tinuous coordination between several involved agencies. The that the North Carolina DOT (NCDOT) and Michigan DOT NCDOT Safety and Traffic Operations Committee is com- (MDOT) have used to better manage work zones. The NCDOT posed of representatives from the WZTC Section, the NCDOT Traffic and Safety Operations Committee is tasked with eval- field office, safety engineers, incident management personnel, uating work zones before any significant changes or when public safety agencies, North Carolina State Highway Patrol crash rates and speeds increase in the work zones. In Michi- (NCSHP), the public information representative, and the con- gan, MDOT transportation planners have used microsimu- tractor. These representatives coordinate to ensure the safety lation modeling to evaluate traffic control plans and select the of the workers and travelers, as well as the efficiency of the work plans based in part on their impact on the overall transporta- zone and the transportation network. tion network. The NCDOT Safety and Traffic Operations Committee focuses on significant projects as defined by the Work Zone Safety and Mobility Policy, where mobility and potential safety North Carolina: NCDOT concerns exist. This allows the committee to provide better Safety and Traffic focus and attention to those construction projects, which Operations Committee will allow them to have the greatest positive impact. NCDOT NCDOT has implemented an interagency coordination process guidelines clearly define four activity levels of significance. The for the planning and monitoring of major construction work criteria for determining the level of significance include zones. The coordination process begins before construction, lane closures, annual average daily traffic (AADT), truck traf- ideally in the planning stage, and is continued throughout the fic, additional travel times expected, level of adverse impacts to project. The process is determined by the needs of each unique existing transportation infrastructure/high-volume traffic gen- construction project. Initially, internal planning level meet- erators, duration of traffic impacts and user value or cost. The ings are conducted to establish the scope of a work zone. A coordination process and committee involvement are then project-specific Safety and Traffic Operations Committee based on the determined level and specific needs of the project. is created to oversee the implementation of a work zone. This Coordination for the concept, design, implementation, process is focused on addressing the work zone safety and and monitoring of work zones occurs throughout the life of 35

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36 a construction project, with varying levels of participation. The focus of the Safety and Traffic Operations Committee is in line early planning stages for the traffic management concept of a with the established goals as it works to safely and efficiently project only involve units internal to NCDOT. As the project plan, implement, and monitor the work zones of significant continues to later phases of the design, through implementa- projects. tion and monitoring, a committee is established with stakehold- ers specific to the project area. The committee has an active role Process Development in implementing and monitoring safety and traffic operations in conjunction with each major lane shift or when increases in The impetus for the Safety and Traffic Operations Committee crash rates or speeds are observed. As an extension of this col- meetings was a fatality that occurred within a construction laboration process, the NCDOT Work Zone Traffic Control project work zone. Because of the fatality, a coordination Section, which is part of the Mobility and Safety Division, has meeting with key stakeholders was conducted. These meet- initiated an effort to continually monitor and evaluate the ings continued throughout the remainder of the project. The effectiveness and safety of work zones. Based on observed collaboration was useful and productive; therefore, when the conditions, the committee can initiate speed or safety studies US-70 Clayton Bypass project was nearing construction, it to validate concerns in the vicinity of the construction proj- was decided to hold similar coordination meetings before con- ect. The resulting information is available to guide decisions struction, during construction, and before major traffic shifts. aimed at revising and improving the existing traffic manage- The meetings were held to address upcoming traffic shifts, ment plan. enforcement, speed limits, incidents, public information, and The Safety and Traffic Operations Committee also consid- a construction update on the project. The meetings were again ers the impacts of the project work zone on the surrounding successful, and NCDOT created the Safety and Traffic Opera- network and seeks to efficiently plan for and minimize those tions Committee, which is now involved in significant projects impacts where possible. Lane and ramp closures are carefully and seeks to address the work zone safety and mobility require- considered because of their impact on the surrounding net- ments provided by FHWA, 23 CFR Part 630, Subpart J. work. In addition, modifications or improvements to spe- cific segments of the network may be recommended to Detailed Process handle the additional traffic resulting from the construction project. NCDOT has published Guidelines for Implementation of the Since the inception of this coordination process, the com- Work Zone Safety and Mobility Policy, which outlines the mittee has been responsible for managing the planning and goals, objectives, and strategies for all projects and identifies monitoring of work zones for several significant projects. key stakeholders who are responsible for the implementation Some construction projects have been completed with no of each objective (2). The document also provides a method of major crashes or fatalities. determining the project level of significance, which, in turn, determines the required management practice. Projects that are determined to be significant within the guidelines require Background of Agency the establishment of a Safety and Traffic Operations Com- The NCDOT Traffic Management Unit is one of six technical mittee composed of representatives from the agencies out- units within the Transportation Mobility and Safety Branch. lined above. The Traffic Management Unit consists of the Congestion Man- The Safety and Traffic Operations Committee meetings are agement Section, the Municipal and School Transportation conducted to evaluate the impact of the work zone on traf- Assistance Section, and the WZTC. Based on the NCDOT's fic on the major routes. Meetings are conducted before the mission statement and goals, the WZTC Section is primarily implementation of the traffic management plan and continue tasked with making the infrastructure safer and more efficient throughout the life of the construction project. Corridors in and around work zones. are designated as major routes based on the project location The WZTC Section regularly coordinates with municipali- and the perceived regional impact of the work zone. Instead ties, highway patrol, emergency responders, other department of conducting monthly scheduled meetings, the meetings are branches, and other agencies. The WZTC Section is respon- established based on key milestones of the project and when sible for developing traffic management plans that maintain certain issues are identified within or in the vicinity of the mobility and safety through a work zone. In addition, the per- work zone. The milestones include scheduled traffic shifts or formance evaluations for each staff member within the depart- changes in the work zone that can result in major impacts on ment are directly connected with the department's goals; staff traffic. members are encouraged to evaluate current operations and The work zone plans are reviewed for effectiveness based on implement strategies that directly seek to reach these goals. The observed conditions in the work zone. The field personnel,

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37 contractor, and law enforcement agencies provide input into Several key integration points were identified in the NCDOT the actual traffic conditions experienced in the work zone. Safety and Traffic Operations Committee process, including the Increases in speed, increases in crash rates, and other negative following: trends observed are discussed at the meetings and possible solutions are presented. Integration between the NCDOT Division Office, the The committee coordinates to identify viable mitigation NCDOT Work Zone Traffic Control Section, and the con- strategies in response to the issues observed in the work zone. tractor to review work zone traffic control plans; Possible solutions include ramp closures, added presence of Integration between NCDOT, the contractor, and the law enforcement, or restrictions in the contractor's available NCSHP to review final plans before implementation; working hours. The strategies are implemented and continu- Integration between NCDOT and the contractor for revised ally monitored for effectiveness until other negative trends work zone plans before implementation; are identified or the construction project is complete. Suc- Integration across all players to monitor performance of the cessful implementation of effective strategies also can lead to work zone once implemented; policy-level changes to guide future traffic management plans Integration between agencies to review potential solutions and work zone implementations. when issues are identified and implemented; and An example of the process used by the Safety and Traffic Coordination with North Carolina's Information Manage- Operations Committee is shown in Figure 4.1. ment Public Affairs, Construction and Traffic Control Figure 4.1. Detailed business process diagram of NCDOT Safety and Traffic Operations Committee.

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38 (IMPACT) group for public information assistance to pro- schedule and under budget while maintaining a safe work envi- vide outreach and information specific to the work zone. ronment for its employees. Since larger construction projects can include daily liquidated damages for delayed completions, Integration also is encouraged because of the required traf- the contractor is always focused on efficient and safe operations fic management plan process. The WZTC Section must pro- within the work zone. The contractor is aware of daily experi- duce traffic management plans for every construction project ences in the work zone and can identify unsafe scenarios within on NCDOT-maintained roadways. Any modification to the the work zone and when traffic patterns, such as increased work zone must be based on traffic control plans sealed by a speeds, begin to change. The contractor coordinates with field professional engineer. Each time there is a change, a new set of personnel on a daily basis, but the Safety and Traffic Opera- plans are developed and sealed. As modifications are made in tions Committee provides a means for the contractor to com- the field, it is important for the changes to be documented in municate concerns with the WZTC Section, NCSHP, incident the existing plans. It also is important that detailed meeting management, and public information personnel. minutes are captured for each Safety and Traffic Operations The committee establishes relationships and networks of Committee meeting. Since the work is occurring in an active informed individuals that build trust with their partners to work zone, the resident engineer should maintain these records reach a common goal. These partnerships increase the safety through the construction life of the project and as long as state and mobility of work zones for significant projects throughout law requires. North Carolina. They also influence coordination among the same agencies that may communicate on other transportation projects. Types of Agencies Involved The Safety and Traffic Operations Committee includes partic- Types of Nonrecurring Congestion Addressed ipants with a vested interest in maintaining a safe and effective work zone. The NCDOT WZTC Section is responsible for the As stated, work zones are categorized as planned events, but can design and management of work zones for all roadway projects generate long-term effects on traffic. Work zones modify the across North Carolina. The NCDOT Division is responsible for roadway operations for specific time periods, and these modi- the construction of the roadway projects and works closely fications must be evaluated to minimize impacts to mobility, with the WZTC Section on issues or questions regarding safety, and travel time reliability. The NCDOT Safety and Traf- the work zone traffic control plans. Additional stakeholders fic Operations Committee is focused on continually monitor- include local agencies that can be affected by rerouted traffic, ing the effect of a work zone on the roadway capacity. The emergency management services and emergency responders committee also plans for secondary incidents and considers who need uninterrupted access to the work zone during inci- how emergency responders can efficiently respond within the dents, the Traffic Systems Operations Unit that oversees pub- work zone. Additionally, construction contracts specify that the lic information for larger construction projects and manages contractor will be required to clear incidents in a set amount of the statewide incident management and traveler informa- time and requires that a towing company be identified within tion systems for 511 and the web, Traffic Safety Unit, and the the contract as a subcontractor. NCSHP that is responsible for law enforcement on North Not only does the committee consider potential incidents, Carolina's highways. but it also attempts to minimize the incidents that occur by These stakeholders collaborate through the Safety and Traf- carefully establishing the appropriate speed limits within the fic Operations Committee, which provides opportunities to work zone. Higher work zone speeds increase the safety risks develop relationships and trust. The committee establishes a for the motorists and workers in both quantity and severity. network of informed individuals who seek to provide the Higher speeds, increased crash rates, and ineffective lane shifts public with safe and reliable transportation throughout North have a direct impact on travel time reliability within the work Carolina. The relationships and networks that are established zone. The committee has established a process to identify, carry over into other aspects of the transportation network evaluate, and implement mitigation strategies to offset nega- as well. For example, through efforts to successfully imple- tive impacts on travel time reliability and these strategies have ment tougher penalties for speeding through work zones, the proven successful in recent projects. NCDOT has developed a strong relationship with the NCSHP. This relationship and foundation of trust has carried over into Performance Measures the Safety and Traffic Operations Committee. The committee also provides the contractor with another The committee has identified specific performance mea- avenue to seek direction and communicate concerns. The con- sures, such as speed and crash rates, to continually evaluate the tractor is driven by a need to construct the roadway project on safety and mobility of the work zone. When these measures