1. University of Colorado A Line and B Line Grade Crossing Update

2. Positive Train Control (PTC)
PTC is not a Technology!
PTC is a Federal Mandate
Train separation or collision avoidance
Line speed enforcement
Temporary speed restrictions
Rail worker wayside safety
RTD’s Primary Train Control System
Network Utilizes Wireless & Fiber Communication
Functions as a “MOVING” Block System
RTD’s Current PTC Efficiency is at +98%
DTP selected Wabtec I-ETMS system
because it is an industry leader

3. Automatic Train Control (ATC)
Conventional Train Signaling System
Utilized in USA Since 1920’s
“Fixed Block” System
Utilizes Track Circuit Technology
Incremental Speed Restrictions
DTP selected Siemens/Alstom & GE
because they are industry leading
suppliers

4. Grade Crossing Activations & Prediction
Conventional Activations
Function of the ATC System
“Fixed” Approach Lengths
Based off Civil Track Speed
System Fails Safe and
provides the minimum 20 second warning time required by law
Wireless Activations
Utilizes the PTC System Technology
Constant Communication with Crossing Equipment
“Pings” Approximately 10x per Second
Provides dynamic control of crossing

5. Types of Grade Crossing Activation Systems
Traditional Predictors
Utilized by Many Freight Rail Roads
Will not Function with RTD’s System
Low Voltage AC current in Rails
Incremental Train Control System (ITCS)
Utilized by Some Commuter Rail Roads
Low Voltage AC current in Rails Combined with Track Circuits
Interoperable Electronic Train Management System (I-ETMS)
Technology Utilized on RTD’s System
Utilizes Wireless Technology
Is an overlay to the Traditional ATC System
Functions in a AC Electrified Environment

6. Types of Grade Crossing Activation Systems
Multiple
Conversations!!!!
Whispers…………………
Why Can’t RTD Utilize Traditional Predictors?
RTD’s System is Powered by 25,000 Volt AC
The Residual AC Current is Returned through the Track Rails
Cannot Distinguish between Return Current and the Predictors

7. Conventional vs. Wireless Approaches
Conventional Warning – Fixed Prediction Based on Max Speed
Contract is Locked
Traffic Signal Clearing
Warning Time
Wireless Warning – More Accurate Prediction
Contract is Locked
Traffic Signal Clearing
Warning Time

8. Grade Crossing Approaches
Contract is Locked
Constant Warning
Traffic Signal Clearing
Warning Time
What Causes the Variability?
Operator Handling Behavior
Station Dwell Time
0 to 79 MPH Acceleration/Deceleration
Trespasser
Dispatcher Hold
Issue at Adjacent Crossing
Variability

9. Union Pacific Railroad
RTD Commuter Railroad

10. Entrance Gates
Exit Gates

11. Dahlia Grade Crossing Approach Length
8,245 Foot Southbound Approach

12. Time Measurement & Performance Criteria
Currently in Negotiation with FRA
Provides FRA with Basis to Regulate
Based from American Railway Engineering & Maintenance-of-Way Association (AREMA) Communications and Signals Manual

13. Dahlia Grade Crossing – Performance Data

14. Steele Grade Crossing – Performance Data

15. Sable Grade Crossing – Performance Data

16. Driver Behavior Concerns
Effects of Warning Time on Driver Behavior and Safety at Grade Crossings Study
Warning Times in Excess of seconds caused many more drivers to engage in risky crossing behavior.
Most drivers expect a train to arrive within 20 seconds from the moment the activation begins.
Drivers begin to lose confidence in the traffic control system if the warning time exceeds approximately 60 seconds.
Suggested warning time guidelines (20 sec minimum, sec desirable, 60 sec maximum)
Four-quadrant gates should be used if 10% of warning times exceed 60 sec.
Reference: Assessment of Warning Time Needs at Railroad Highway Grade Crossings with Active Traffic Control, Stephen H. Richards and K.W. Heathington, Transportation Research Record 1254

17. Grade Crossing – Timeline
2010 – Denver Transit Partners Selects Technology
April-2015 (CU A-Line)
Revenue Service
FRA Waiver Issued
October-2016
FRA Waiver #3, Action Items Established
February-2017
FRA Waiver Extension
Q Wayside Construction, Testing & Commissioning Substantially Complete
July-2016
(B-Line) Revenue Service
December-2016
FRA Waver Extension
July-2017
FRA Waiver Extension
Data Reporting
Performance Demonstration
Operator Training
Crossing Optimization
Establish Performance Criteria
With FRA
FRA Action Items

18. Questions?