Perform adequate analyses and tests to design, calibrate and validate the capabilities of a bridge security monitoring system in order to reduce false alarms.

Experience from iFlorida Model Deployment

Florida,United States

Background (Show)

Lesson Learned

The iFlorida Bridge Security Monitoring System consisted of a software and hardware system that automatically monitored video images of the bridge and its vicinity and activated an alarm whenever suspicious activities might be occurring near the bridges. When an alarm was activated, the system would allow operators to review real-time and archived video footage to identify the source of the alarm and then mobilize and monitor response activities, if a response was required. Before deciding to deploy a Bridge Security Monitoring System, the FDOT performed a review of the security risks to identify the highest priority risks that could be addressed most cost effectively. The applicable parts of the Homeland Security Comprehensive Assessment Model (HLS-CAM), developed by the National Domestic Preparedness Coalition, was used in order to gather information on the costs and effectiveness of such a system. The security monitoring system was deployed at two bridges. In the process of deploying and using the system, the FDOT identified several lessons learned that might benefit others wishing to deploy similar systems:
  • Perform adequate tests to calibrate and validate the capabilities of a bridge monitoring system. Many different types of tests were available for FDOT to use to detect threats and sound alarms. While the software made these tests easy to define, it was difficult to define them in such a way that reduces the number of false alarms. Special expertise, if not available at the DOT, must be hired to perform the specialized calibration, testing, and validation.
  • Ensure that the number of false alarms is not excessive. The high number of false alarms in the iFlorida Bridge Security Monitoring System meant that alarms were often ignored. Testing the number of false alarms, and adjusting the system until an acceptable number was generated, might have made the system operators more responsive to alarms that did occur.
  • Provide provisions for adjusting the alarm plan during special circumstances, such as construction activities or the presence of a disabled vehicle. The operators at the District 5 RTMC noted that a number of common events, such as construction activities or a disabled vehicle on the bridge, would sometimes generate a large number of false alarms. The system did not include a convenient way to adjust the operating parameters when such situations occurred.
  • Conduct a cost effectiveness analysis. The FDOT demonstrated that a video monitoring system could be used to identify potential threats to a bridge provided the false alarms can be brought to an acceptable level. However, the cost of monitoring the two bridges was high—more than $860,000 for design, deployment, and two years of operation. Since the likelihood of attack at these specific bridges was relatively low, a complete HLS-CAM review would likely have identified more cost-effective ways to increase transportation security.
  • Locate the video processing and archiving equipment away from the bridge or the asset being protected, preferably in a climate-controlled environment. The FDOT noted that, with the video archiving hardware deployed in the field, a catastrophe at the bridge would likely destroy the archived video. Archiving the video at a location separate from the monitored asset would protect the archived video from damage, so that it could be used to support post-catastrophe analyses. The FDOT also believed that the equipment deployed in the field would have operated more reliably if deployed at the climate controlled environment of the Deland office.
The effectiveness of the Florida’s bridge security monitoring system was compromised by the occurrence of high number of false alarms. In a security operations center with operators devoting full-time attention to video surveillance, such false alarms could be easily dismissed by operators and might be a minor nuisance. At the District 5 RTMC, however, operators were primarily concerned with traffic operations and could not review and dismiss frequent bridge security alarms. In this type of environment, the acceptable number of false alarms is low. Given the uncontrolled environment around most bridges, it was not clear whether existing video analysis systems could provide a low enough level of false alarms to make the system useful without having full-time operators available to discount false alarms.

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iFlorida Model Deployment Final Evaluation Report

Author: Robert Haas (SAC); Mark Carter (SAIC); Eric Perry (SAIC); Jeff Trombly (SAIC); Elisabeth Bedsole (SAIC): Rich Margiotta (Cambridge Systematics)

Published By: United States Department of Transportation Federal Highway Administration 1200 New Jersey Avenue, SE Washington, DC 20590

Source Date: 01/30/2009

EDL Number: 14480

URL: https://rosap.ntl.bts.gov/view/dot/3977

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Lessons From This Source

Assess security risks, threats, vulnerabilities, and identify countermeasures to ensure operations of transportation management centers.

Be flexible to use data from various sources, such as the highway police patrol’s incident data, user feedback, and monitoring stations, to develop a statewide traveler information system.

Beware of challenges involved in developing an integrated statewide operations system for traffic monitoring, incident data capture, weather information, and traveler information—all seamlessly controlled by a central software system.

Beware of costs, utility, reliability, and maintenance issues in deploying a statewide transportation network monitoring system.

Beware of the limitations of using toll tags in order to calculate travel time on limited access roadways and arterials.

Beware that software development for ITS projects can be utterly complex, which demands avoiding pitfalls by following a rigorous systems engineering process.

Define a vision for software operations upfront and follow sound systems engineering practices for successfully deploying a complex software system.

Deploy a variable speed limit system only after the software systems required to support it are mature and reliable.

Design traffic video transmission systems around the constraints of bandwidth limitations and provide provisions for remote configuration of video compression hardware.

Develop an accurate, map-based fiber network inventory and engage ITS team in the construction approval process.

Develop an effective evacuation plan for special event that gathers a large audience and consider co-locating the responding agencies in a joint command center.

Ensure compatibility of data format of the field-weather monitoring sensors with the central software in the transportation management center.

Ensure that experienced staff oversee the development of a complex software system and thoroughly follow systems engineering process.

Ensure that Highway Patrol's CAD system operators enter key information needed by the transportation management center operators.

Establish a well defined process for monitoring and maintenance before expanding the base of field equipment.

Estimate life-cycle cost of ITS technologies as part of procurement estimates in order to assess the range of yearly maintenance costs.

In developing software for automated posting of messages on dynamic message signs, focus on the types of messages that are used often and changed frequently, and also include manual methods for posting.

Incorporate diagnostic tools to identify and verify problems in the transmission of video in a transit bus security system.

Perform adequate analyses and tests to design, calibrate and validate the capabilities of a bridge security monitoring system in order to reduce false alarms.

To support statewide traveler information services, design and implement reliable interface software processes to capture incident data from the local and highway patrol police’s computer aided dispatch systems.

Use simple menu choices for 511 traveler information and realize that the majority of callers are seeking en route information while already encountering congestion.

Lesson ID: 2010-00518