United States
The Alaska Department of Transportation & Public Facilities (DOT&PF) sponsored a research project titled, Evaluation of Overheight Vehicle Warning Devices, to synthesize existing data and previous research to develop a comprehensive examination of the state-of-the-practice for oversized vehicle warning systems. Of the 49 state departments of transportation (DOTs) contacted, twenty-nine completed interviews. Eighteen state DOTs did not have an overheight detection system in use. The other 11 state DOTs had a wide range of systems in use: 2 passive and 9 active. The nine active systems involved detection and directive warning signs.
Based on survey responses, initial costs of active laser- and infrared-based early warning detection systems (EWDS) vary considerably ranging from $7,000 to $70,000. Although costs data are not widely available, the O&M costs are considered relatively minimal, regardless of the type of system deployed, ranging from $1,000 to $2,500.
One of the findings from the research was the cost of technology-based solutions—the laser and infrared warning systems, in comparison to traditional strategies that use little or no technologies at all. The table below excerpted from the source report shows the cost of several potential EWDS, along with the laser and infrared warning solution.
Costs of Potential Overheight Detection Solutions
Solution
|
Initial Cost (capital)
|
Power Required
|
Assessed Effectiveness
|
Problems
|
---|---|---|---|---|
Warning signs and lights |
Low
|
Yes
|
Unknown | Unknown |
Passive-rigid |
Low – Moderate
|
No
|
Slight reduction | Possible damage to truck and other nearby vehicles |
Passive-nonrigid |
$2K – $35K
|
No
|
Slight reduction | Inaudible over road noise for drivers |
Laser and infrared systems w/signs |
$7K – $70K
|
Yes
|
Reduction | False positives |
Enforcement/Penalties |
Unknown
|
No
|
Unknown | Unknown |
Police Escort |
Unknown
|
No
|
Unknown | Still prone to human error |
The survey results indicate that most states (73%) believe their EWDS reduce incidences of overheight vehicles striking infrastructure components. For the laser- and infrared-based solution, which is reported to be a “good choice” if the power requirements can be overcome, the wide variation in capital costs ($7,000 – $70,000) is due to the fact that each system vendor packages its system differently. Some vendors perform the equipment installation and the labor cost is included in the total deployment costs. Also, some vendors select from multiple systems or product lines offered to meet the needs of the customer. Most systems use line power, rather than solar power, to reduce O&M cost and increase reliability.
Mitigating Overheight Vehicle Crashes Into Infrastructure: A State of the Practice
System costs: $7,000 to $70,000.