Safety > Highway-Rail Intersection                                  Printer-friendly version

• Introduction
  • What are Intelligent Transportation Systems at Highway-Rail Intersections?
  • Rationale for using ITS at HRI
• System Description
  • Technologies Used/ Case Studies: Key Results, Benefits, Costs, Where is it Implemented?
• Assessment
  • Benefits
  • Implementation and Operational Challenges
  • A Timeline of Federal Policies Endorsing ITS Applications at HRI
• References

INTRODUCTION

What are Intelligent Transportation Systems at Highway-Rail Intersections?

Over the past 10 years, ITS technologies have increasingly been applied to Highway-Rail Intersections (HRI) in an effort to improve their safety, efficiency, productivity, control, and communication. Such technologies include digital data communications, transponders installed in the wayside or embedded in the railroad tracks, train location system, onboard computers, and date radio. Deaths at highway-rail grade crossings rank #1 among rail-related fatalities, making the implementation of advanced accident-prevention technologies essential.

Rationale for using ITS at HRI

Accidents at highway-rail intersections are a serious problem in the US. In October 1995 a school bus transporting 35 school students stopped at a grade crossing in Fox River Grove, Illinois and was struck by a commuter train. Seven students were killed. Accidents like this are a recurring problem at highway-rail intersections. The following chart shows the number of fatalities, injuries, and accidents that have occurred at HRI between 1970 and 1999.

Link to table presenting data compiled by the Bureau of Transportation Statistics.

While on the decline, tragedies like the Fox River Grove incident continue to occur. The high numbers of fatalities, injuries, and accidents in this table have necessitated the implementation of advanced accident-prevention measures. Moreover, these statistics explain why archaic and ineffective warning signals at highway-rail intersections are being replaced with technologies like ITS.

At public highway-rail crossings there are currently two basic types of warnings: passive and active warning devices. Passive warning devices are static traffic control devices indicating the presence of an at-grade crossing (i.e. crossbucks). Active highway-rail crossing devices indicate the presence of an approaching train (i.e. flashing signals). These dated forms of warning signals are insufficient to bolster the steadily rising demands of a highly mobile society. ITS technologies can help transform the current rail transportation system into a network with increased accessibility, greater productivity, and enhanced safety and efficiency.

SYSTEM DESCRIPTION

Technologies Used/Case Studies: Key Results, Benefits, Costs, Where is it Implemented?

The following ITS technologies are aimed at enforcing safety and control at highway-rail intersections See our Telecommunications Diagram on HRI for more information):

Automated Enforcement of Lowered Crossing Gates
Vehicle Proximity Alert System (VPAS)
Positive Train Separation (PTS)
Advanced Warning for Railroad Delays (AWARD)
Second Train Warning (STC)
In-Vehicle Alert System
Four Quadrant Gate System with Obstacle Detection and Train Control
Non-Intrusive Train Detection
Intelligent Grade Crossing integrated with other ITS technologies

Automated Enforcement of Lowered Crossing Gates
Automated enforcement uses sensor technology and high-resolution cameras to photograph motorists running under or around railroad crossing gates. It is triggered when vehicles cross over inductive loop detectors after the crossing gates have started down. The cameras take two photos of the vehicle, its license plate, and the driver's face. On each photo is the date, time, speed of the vehicle, and number of elapsed seconds since the red flashing lights were activated at the crossing.

The Metropolitan Transportation Authority (MTA) in Los Angeles initiated the most ambitious application of automated enforcement of lowered gates in 1992. Violation rates at enforced locations along the Metro Blue Line decreased significantly as a result of the enforcement, prompting the MTA to install photo enforcement equipment at 17 locations. The cost of a photo enforcement installation at an intersection ranges from $40,000 to $75,000.

Vehicle Proximity Alert System (VPAS)
Vehicle Proximity Alert Systems are transmitters and receivers that provide automated visual and audible warnings about train activity to motorists who are in the vicinity of a HRI.

Section 1072 of the Intermodal Surface Transportation Efficiency Act required the testing of VPAS at crossings that lacked active warning devices. The VPAS prototypes were tested in Pueblo, Colorado by the Transportation Technology Center in 1995 and 1996. Although the testing determined that VPAS should be used for decreasing vehicle and train collisions at HRI, none of the systems used were suitable for further testing. In compliance with the ISTEA Section 1072, the Secretary of Transportation continue to implement VPAS programs where appropriate.

Positive Train Separation
PTS is an enhanced overlay system that uses digital radios and computers onboard locomotives to automatically control train movement. PTS includes collision protection features and optional onboard display capabilities which enforce safe train operation.

A recent PTS testing project took place on railway extending from Blaine, Washington to Pasco, Washington. PTS prototype equipment installed on the locomotives included wiring harnesses, brake size modifications, sensors, housing and brackets. This PTS system was successfully tested and developed, and the project was completed in 1998.

Advanced Warning for Railroad Delays (AWARD)
AWARD technology uses acoustic sensors and radar speed guns to alert motorists of delays at HRI due to train activity or blockage.

An AWARD program was instigated in San Antonio, Texas in 1998. Acoustic sensors and radar speed guns were placed upstream of three locations near the intersection of Woodlawn Avenue and the Union Pacific Railroad line parallel to Interstate 10 in San Antonio. The sensors detected the presence, length and speed of trains approaching the crossings. The duration(s) of blockage were calculated, and the predicted delays were then disseminated in three ways:

1. Variable message signs upstream to the crossing alerted drivers to take alternate routes or freeway exits to avoid the delay.

2. The TransGuide traffic management center included the delay information in up-to-the-minute link speeds distributed via the Internet, kiosks and in-vehicle displays.

3. Emergency service vehicles such as ambulances used the delay information to plan their routes in real-time.

The project cost is estimated at $303, 405.

Second Train Coming (STC)
A second train coming system uses railway sensors and a Changeable Message Sign (CMS—also referred to as Variable Message Signs) to warn drivers of the presence of a second train which is approaching the crossing soon after an initial train has cleared the crossing. After the crossing gates have been lowered, sensors in the track detect a second train coming and then activate the CMS. The CMS usually displays a STC warning such as "Danger: Second Train Approaching." The most common types of CMS use fiber optics, light-emitting diodes (LED), reflective disks, or a combination of these technologies.

The Maryland Mass Transit Administration (MMTA) enacted a second train coming project in1998 and 1999. MMTA used an LED matrix to display the warning. Modified signal circuits controlled the STC sign. Video taped observation indicated that risky driver behavior decreased by 36% after the system was installed at this location.The Los Angeles County Metropolitan Transportation Authority has also tested and installed a STC sign on its light rail transit line. A final report is expected in September 2001.

In-Vehicle Alert System
This system uses wireless vehicles and roadside communication antennas to alert roadside drivers of train presence. The trackside unit picks up a signal from the railroad’s train detection electronics and transmits that signal to antenna-signs. The in-vehicle display alerts drivers of train presence at HRI using both visual and audible signals. When a receiver in the driver’s vehicle comes within range of a radio signal emitted at a crossing, the system can inform the driver of 1) the proximity of his or her vehicle to the crossing and 2) whether or not a train is present at the crossing.

An in-vehicle alert system project was carried out by the Minnesota Department of Transportation, 3M Corporation, and Dynamic Vehicle Safety Systems (DVSS) from 1995 to 1998 in Glencoe, Minnesota. In addition, the Illinois Department of Transportation and a team lead by Raytheon Company are currently testing a similar in-vehicle warning system in the Gary-Chicago-Milwaukee Corridor. A final evaluation of this project is expected in late 2001.

Four Quadrant Gate System with Obstacle Detection and Train Control
Four quadrant gates block both sides of the highway at each side of a HRI so that waiting vehicles cannot cross the tracks. The train control component includes sensors that send a message via track circuitry and wayside controls to the train as it approaches the grade crossing. These controls can bring the train to a safe stop if an obstacle is detected at the crossing.

The Federal Railroad Administration and the Connecticut DOT installed a four quadrant gate system at the intersection of School Street and the Amtrak rail line in Groton, Connecticut. Testing took place from January 1999 through the end of September 2000. This $1 million project is expected to be completed in January 2002.

Non-Intrusive Train Detection
This system uses non-intrusive sensors such as video cameras to detect the presence, speed, and length of trains approaching designated crossings. It also uses these sensors to calculate the duration of crossing blockages. Its purpose is to develop an integrated system for detection of trains so that special timing plans can be selected when trains are present and/or approaching HRI.

Minnesota’s Guidestar, a Congressionally funded statewide ITS program, completed an initial scoping report in Moorhead, Minnesota in June 1998. In December 2000, Guidestar concluded deployment demonstration of video-based train detection, wireless communication and a host-end system. Expansion of the project is currently underway and is expected to be fully operational in late 2001.

Intelligent Grade Crossing integrated with other ITS technologies
Intelligent Grade Crossings are locations where ITS for roadways come together with Intelligent Railroad Systems, and in particular, Positive Train Control (PTC) systems. Unlike traditional railroad signal systems, PTC systems provide continuous, real-time information on train location and speed. New York State Department of Transportation partnered with Alstom Signaling to integrate the following forms of ITS technologies with Intelligent Grade Crossings:

• Constant Warning Time: The Intelligent Grade Crossing provided a constant 30-second warning time to drivers, regardless of the train’s speed or type, by activating both the crossings active warning signals as well as nearby variable message signs.

• Stalled Automobile Detection: A combination of conventional loop detectors and high-tech video-based sensors detected if a vehicle was stalled on the tracks, if traffic backed up onto the tracks, or if a vehicle was unable to exit the crossing area. The Intelligent Grade Crossing Systems could turn the traffic signal lights to green, allowing vehicles to exit the crossing, thus clearing the queue from the crossing. If the crossing was blocked, a signal was sent to the locomotive engineer in time to stop the train before it reached the crossing or slow the train down as much as possible. A back-up system could also stop or slow the train—equipped with Positive Train Control (PTC) technology—automatically, if necessary.

• Emergency Vehicle Priority: If an equipped emergency vehicle needed to cross the tracks, it could send a message via wireless communications to the Intelligent Grade Crossing. The ICG then caused the train to safely brake prior to the crossing, if the train’s speed and distance allowed. Otherwise, the request was denied until the train had passed.

• Minimize Gate Down Times: The Intelligent Grade Crossing minimized gate down times, making operation of the signal system more reliable to drivers.

• Variable Message Signs: The Intelligent Grade Crossing allowed nearby variable message signs to display messages that informed drivers of current conditions at the crossing. Messages displayed included "Train Approaching", "Crossing Delay", "Exit Lane Blocked" and "Train in Station".

A final report of the cost/benefit analysis of these projects is expected in 2002.

ASSESSMENT

Benefits

• Safety: Accident, injury, fatality reduction and prevention; Increased roadway driver awareness.
• Efficiency: Exchange of real-time data between train and traffic controllers at HRI; Reduced risk for manufacturers and implementers; People and goods effectively moved per unit time.
• Productivity: Cost reduction in transportation of goods and people.
• Control: Nationwide interoperable and coordinated transportation systems; ITS tracks and monitors train activity.
• Communication: Improved real-time communication between train operators, traffic control centers, and roadway vehicles.

Implementation and Operational Challenges

• Regulation of workload management for drivers and engineers.
• Coordination of HRI signals with roadway signs.
• Lack of multi-organizational cooperation, including many levels of government agencies.
• The Manual on Uniform Traffic Control Devices (MUTCD) needs to be expanded to include future HRI development.
• Motorists may also be confused by HRI signs and signals that differ slightly from standard highway traffic signals. In addition, there are no national regulations on motorist responses to flashing lights (i.e. each state determines its own laws regarding these lights), which can lead to misunderstandings at HRI.
• Fear of tort liability exposure via introduction of new technology.
• Human factors: need for consistent reliable signs and signals.
• Lack of interoperability and standards for ITS at HRI.
• Pedestrians, jogger, and bicyclists continue to walk over crossing, believing that they can hear oncoming trains or that the train will stop before colliding with them.

A Timeline of Federal Policies endorsing ITS applications at HRI

• 1991: The Intermodal Surface Transportation Efficiency Act establishes ITS America and National ITS Architecture.
• 1993: The Joint Program Office is named "Principal Architect and Executor of ITS Leadership" and given the authority to coordinate and guide policy.
• 1994: Congress passes the Highway-Rail Grade Crossing Safety Act. Part of this Act is an Action Plan which identifies a wide variety of initiatives (55) in six separate categories:

• 1997: Highway Rail Intersections (HRI) are named the 30^th User Service within the National ITS Program Plan.
• 1999: The Federal Railroad Safety Enhancement Act is passed. This Act addresses the human factor challenges in the railroad industry, highway-rail grade crossing safety, and other significant rail safety issues

REFERENCES

Carroll, Anya, Oxley, Cassandra. ITS Technology at Highway-Rail Intersections. Putting it to the Test. Proceedings from the ITS Joint Program Office: Highway-Rail Intersection Evaluation Workshop. May 1999. Link to Report

Chappell, Debra. Comparative Analysis of Innovative Highway-Rail Grade Crossing Projects: An Interim Report. IT’S America 10^th Annual Meeting. Session 102: HRI Evaluation Results. May 4, 2000. Link to Report

Fariello, Brian G. San Antonio AWARD Project. San Antonio District: Texas Department of Transportation. Presented May 2000. Boston, MA. Link to Report

Marston, Pamela P. Changeable Message Signs: Avoiding Design and Procurement Pitfalls. Link to Report

Polk, Amy Ellen. The Use of ITS to Improve Safety and Mobility at Highway-Rail Grade Crossings. Presented at the California Public Utilities Commission Annual State/Railroad Meeting in San Diego, CA. August 2001. Link to Report

Woll, Thomas. Establishment of the Highway-Rail Intersection User Service and the Need for the Development of Standards. June 23, 1999. Federal Railroad Administration. Link to Report

Woll, Thomas. Intelligent Transportation Systems for the Highway-Rail Intersections. AREMA Committee 36 Meeting. March 2000. Link to Report

US DOT: Research and Special Programs Administration: John A. Volpe National Transportation Systems Center. Vehicle Proximity Alert System for Highway-Railroad Grade Crossing Prototype-Research: Safety at Highway-Railroad Grade Crossings. Washington DC, Cambridge MA. April 2001. Link to Report

Federal Railroad Administration. PTC Implementations: Pacific Northwest Corridor. Positive Train Separation (PTS) Project. Link to Report

In-Vehicle Signing for School Buses at Railroad-Highway Grade Crossings. SRF Consulting Group. Minneapolis, MN. August 1998. Link to Report

FRA. Office of Safety Analysis/Statistical Report. Last Updated September 6, 2001. Link to Report

US DOT. FRA Memorandom. April 1996. Link to Report

US DOT. FRA. Compilation of State Laws and Regulations Affecting Highway-Rail Grade Crossings. Link to Report

Federal Railroad Association: Highway-Rail Grade Crossing Safety Action Plan: Executive Summary. Link to Summary

Federal Bureau on Transportation Statistics: Table 2-5. Link to Table

Author : Lauren Smith, Last Update 11/01/01