In-Pavement Warning System AT Device Trial

Acknowledgements Mitch Tse Ngan Truong May Huang Mitch started investigating this in 2006. Ngan resurrected the project in 2012 and pushed it through the TCD trial process for over two years and May delivered the project from 2015-2016. I’m just presenting on the work they did.

Reducing Red Light Running We wanted to focus on dog leg intersections with confusing lantern placement as well as sites with RLR problems.

Reducing Red Light Running This site was a midblock crossing at a motorway off-ramp in the CBD. There was a fatality here and we decided to trial the treatment here for traffic coming off the motorway.

Reducing Red Light Running Rem Rd Installation

Evaluation of Two Locations Remuera Town Centre from Dec 2015 Data from 1 weeks before, 2 weeks after Fanshawe St from mid 2016 Data from 2 months before and 2 months after 700 hours of video footage reviewed We seek to reduce red light running by reinforcing the red signal with LED road markers. https://www.youtube.com/watch?v=h4deiK0kS40 An alternative method of validating data is needed.

Remuera Results Average daily incidents of red light running based on video. The eastbound direction saw about a 55% reduction in red light running. The westbound direction saw a 33% reduction in red light running.

Fanshawe Results Average daily incidents of red light running based on video. This trial was only in one direction and a 33% reduction in red light running.

Fanshawe Average Hourly This just shows the average hourly incidents for fanshawe. It shows how the greatest improvements are in the inter peak periods.

Lessons Learnt Maintenance / Install problems Vehicle paths SCATS Red light running volumes Accidental RLR rates It has now been 15 months since installation at Remuera rd and at least half of the road markers are no longer working. We still don’t know the cause, it could be incorrect installation or faulty hardware, but it is probably the poor road surface causing the failure. We are still investigating this. One problem is the wheel paths that ended up with markers right underneath the path of trucks. It is difficult to place due to the width of the lanes at Remuera. We used SCATS RLR counters to evaluate initial sites we chose. Validation against video data showed significant discrepancies between RLR counters and actual events. At Remuera the loops counted an average of 160 RLR per day. Video data shows this value to be 26 RLR from 7-7. That’s a huge discrepancy. Post install the RLR counters were giving counts of 300+ per day. Based on the video data, only 3 cars per day ran the red based on seeing the downstream green. Most of those stopped right after the stop line. Perhaps the original issue isn’t as bad as we first thought it was based on complaints from the locals.

Future Work Placement and configuration New sites and intersection type Our original intention was to use these for dog leg intersections to reduce RLR, but due to their effectiveness we are considering using these at other locations. We are looking at placing the LED’s further from the stop line to increase visibility to drivers at the stop line .

Conclusions Criteria Validation Effective Device Costly Further trials required More robust site selection criteria is required. More effective validation method required. Device is effective at reducing RLR in general, but costly 25-50k per site. BCR may not stack up Long term maintenance costs may not justify this type of installation. Because the RLR problem is less than we originally thought the BCR of this type of installation can vary wildly.

Other Trials White/Amber markers for dynamic tidal flow lanes Green markers for active bus lanes Directional Arrows for Cyclists Amber/Red lanterns for part time slip lane control May Huang delivering the part time slip lane crossing trial and it is meant to go by June. Hopefully she will be able to report on this next year to SNUG. We are also tagging along with CHCH with their trial for directional arrow for cyclists. We will be trialling it at two intersections.

Part time ped crossing on a slip lane Part time ped crossing on a slip lane. Give way applies when the signals aren’t on. 2 trial sites being developed for later this year.

Questions?