State DOT Intelligent Work Zone deployment scoping guidance materials provide high-level cost estimates as well as duration-based costs for more precise cost estimation.
Intelligent Work Zone (IWZ) deployments can range from motorist advisory systems with traffic monitoring for stopped traffic to work zone intrusion detection systems. Motorist advisory systems can use upstream traffic sensors to advise approaching drivers via Portable Dynamic Message Signs (PDMS). Motorist Warning Systems can use sensors to dynamically warn trucks or drivers that are traveling at an excessive speed. More advanced intrusion detection systems can use sensor technology to detect an intrusion event and issue alerts to workers and drivers. These systems may be designed to alert drowsy or distracted drivers to prompt them to take corrective action, or can provide advanced warnings to workers to enable them to escape the path of an approaching vehicle.
Scoping guidance used by the Minnesota DOT (MnDOT) includes a decision tree to help planners and engineers plan and scope a project to identify the level of deployment and technologies needed to satisfy a range of needs. For example, MnDOT recommends the deployment of an intrusion warning system or an electronic message sign displaying “workers present” when the workers are located adjacent to high-speed open lanes not separated with concrete barriers.
Cost estimation guidance offers both a high-level estimate for situations where duration may be unknown, as well as more precise estimates based on additional information. The high-level estimates are shown in Table 1, and Figure 1, excerpted from the guidance, illustrates the more detailed approach.
|IWZ System Type||High-Level Cost Estimate|
|Mobility and Traveler Information System with one Alternate Route||$280,000|
|Mobility and Traveler Information System with no Alternate Route||$140,000|
|Motorist Advisory System||$75,000|
|Motorist Warning System (per site)||$13,000|
Figure 1: Cost Estimates for Intelligent Work Zone Scoping
Intelligent Work Zone (IWZ) Motorist Advisory System Rental: $75K