Evaluation of LED-Outlined Backplates at Intersections With Light Rail Lines In Houston, Texas

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1 Evaluation of LED-Outlined Backplates at Intersections With Light Rail Lines In Houston, Texas ITS Texas Annual Meeting, November 2015 Jonathan Tydlacka, P.E. (TTI)

2 Why Are We Here Today? Great forum to present evaluations of unique & innovative traffic control devices Gain feedback and comments on the operational concepts

3 METRORail History METRORail Red Line opened in Houston, Texas - January 2004 Extended North - January 2014 Completely at-grade with shared left turn lanes in some areas Line operates from North Loop, CBD, down to Texas Medical Center, and Reliant Park Currently carries about 42,000 passengers per day

4 Initial Operational Issues High Frequency of Accidents (15) in 6 weeks of testing & 1 st month of revenue operation All with motor vehicles All attributed to motorist error Initial safety assessment recommendations Increase visibility of red signal indications

5 TCD Experimentation Stop bar location & visibility Lighted Stop Bar Increase visibility of red signal indications LED-outlined Backplates

6 Evaluation Methodology TCD Experimentation Request Driver Surveys Operational Evaluations Before / After Measures of Effectiveness (violations) Long Term Crash Monitoring Crashes by type/causation Semi-annual reports

7 Lighted Stop Bar Pilot Installation EB Jefferson Street at Main Street FHWA Approved Experiment EX Operational Aspects as Initially Evaluated: Markers operated in a steady red mode during every red signal indication of the traffic signal Markers off at all other times Markers located prior to painted stop line

8 Pilot Installation

9 Replacement System & Additional Locations Several failures at pilot site Pilot site & additional sites outfitted to 3G & 4G system FHWA granted request to expand experimentation

10 Lighted Stop Bar Problems Newer 3G and 4G systems had durability issues Failures of the individual markers and the systems High traffic volumes, moisture, debris penetration all factors leading to failure. Systems had IP addressable markers, so failures were reported BUT The costs for repairs and replacements were too great in terms of dollars and manpower A change was necessary.

11 LED-Outlined Traffic Signal Backplates Around the same time that the first pilot lighted stop bar was being tested, METRO was also testing a pilot location of LED-outlined traffic signal backplates. The backplates were part of the same FHWA Experimentation Request.

12 LED-Outlined Backplates Pilot Installation WB Gray at Main Street FHWA Approved Experiment EX Operational Aspects: Red LEDs create a red border around the standard black traffic signal backplate for each signal head on the approach. Operate in a steady red mode during every red signal indication of the traffic signal & Off at all other times (including red or yellow flash).

13 LED-Outlined Backplates

14 LED-Outlined Backplates Mounted to signal mast arm Two signal faces No backplates before LED-outlined backplates added

15 Evaluation Period LED-Outlined Backplates Results Motorist Violation Data Pilot Site 24-hour Totals of WB Vehicles Left Turn Thru Right Turn WB Violations per Day WB Violations per Day per 10,000 Vehicles RLR* RTOR* RLR RTOR Before (3 Day Average) After (3 Day Average) *RLR = Red Light Running *RTOR = Right Turn on Red Note: RTOR prohibited on all cross street approaches to the Red Line

16 LED Backplate - Vehicle Crash Statistics Crash statistics compiled for 24 months before and after the installation of the LED Backplates. Period Total Crashes Ran Red Light (WB) Before 24 Months After 24 Months

17 Observational Study of Additional Sites Three LED-outlined backplate treatment sites for Before & After Study Westbound Pease at Main Westbound Bell at Main Eastbound Franklin at Main Pease & Bell are five-lane, one-way approaches to the Red Line Replaced standard backplates with LED-outlined backplates Franklin is a three-lane, one-way street Did not have any backplates in before data

18 Observational Study of Additional Sites Before & After Study using recorded video 3 days (three 24-hour periods) of video before 3 days of video after LED backplates installed and activated Approx 5-8 weeks after activation Manually reduced video

19 Observational Study of Additional Sites Several differences from pilot location Mounted to signal poles (one on each side) Pease and Bell sites had backplates before LED-outlined backplates added. Franklin site had no backplates at all before LED-outlined backplates added.

20 Observational Study of Additional Sites Data included traffic volumes and violations Red Light Running (RLR) Right Turn On Red (RTOR) RTOR prohibited on all cross street approaches to the Red Line Some deliberate RLR violations in both before and after periods Removed violations at Pease which occurred after more than 90 seconds of red time Removed violations by emergency vehicles

21 Three Day Average Violation Frequency Before (3 Day Average) After (3 Day Average) 24-hour Totals of WB Vehicles Left Turn Westbound Pease at Main Thru Right Turn WB Violations per Day RLR RTOR RLR WB Violations per Day Day* (Daylight) Night (No Daylight) RTOR RLR RTOR % Change -21% -6% -21% -16% -21% -9% -25% -37% +9% *Note: Day includes daylight and twilight periods of the day.

22 Three Day Average Violation Frequency Before (3 Day Average) After (3 Day Average) 24-hour Totals of WB Vehicles Left Turn Westbound Bell at Main Thru Right Turn WB Violations per Day RLR RTOR RLR WB Violations per Day Day* (Daylight) Night (No Daylight) RTOR RLR RTOR % Change 0% -23% -3% -50% -27% -33% -20% -100% -59% *Note: Day includes daylight and twilight periods of the day.

23 Three Day Average Violation Frequency Before (3 Day Average) After (3 Day Average) 24-hour Totals of EB Vehicles Left Turn Eastbound Franklin at Main Thru Right Turn EB Violations per Day EB Violations per Day Day* (Daylight) Night (No Daylight) RLR RTOR RLR RTOR RLR RTOR % Change -10% -5% +28% -55% +28% -29% +70% -100% -15% *Note: Day includes daylight and twilight periods of the day.

24 Notes on Violation Frequency Reduction of RLR and RTOR at each treatment site With the exception of the special circumstances at Franklin We generally observed reductions for both RLR and RTOR violations for both day and night Appears to have slightly greater effect at nighttime Normalized data to account for different approach traffic volumes Violations per 10,000 cross street approach vehicles Pooled t-test used to determine significant differences in Before vs. After data

25 Normalized Violation Data Study Site Study Period 3-Day Average Number of Violations per Day per 10,000 Vehicles Statistically Significant Reduction in Violations per Day per 10,000 Vehicles? RLR RTOR RLR RTOR Pease at Main Before After NO YES, 90% Confidence Bell at Main Before After NO NO Franklin at Main Before YES, 95% After Confidence NO

26 Additional Observational Study Data Time of violation after onset of red signal (> 2) Signal red more than 2 seconds ( 2) Signal red less than or equal to 2 seconds RLR More RLR in 2 data (about 80%) Reduction of 40% for > 2 Reduction of 25% for 2

27 Crash Monitoring Long-term crash analysis still ongoing for these and all LED-outlined backplate locations Being done to provide additional data points at FHWA & TxDOT request

28 In Summary LED-outlined backplates show potential to supplement the effectiveness of standard TCD s along the LRT Reduction in red light running Reduction in illegal right turn on red movements Helped to reduce RLR and RTOR violations at the treatment sites.

29 METRO s View On Experimental TCD s Working with its local, state and federal partners, METRO plans to continue developing and deploying innovative TCD s where in the best interest of its passengers and the traveling public. METRO is seeking to garner support for interim approval to use these devices within its jurisdiction. NCUTCD (National Committee) is currently making decisions about what is included in next MUTCD

30 For More Information TTI Jonathan Tydlacka, P.E Houston METRO Walter Langford, III