By Dacia Whaul
For motorists tired of traffic jams and long delays while travelling in the city, relief may soon be in sight.
The Public Works Ministry has begun conducting studies geared at improving the flow of vehicular traffic in Georgetown, to reduce congestion and ensure the best possible traffic flow at key intersections.
This is according to Chief Transport Planning Officer Patrick Thompson, who revealed that a citywide study is planned this year following a 2013 analysis of the traffic movements at the Camp and Regent streets intersection, which has received a failing grade for the level of service it offers to motorists.
Thompson, who ob-served that the traffic dynamic in Georgetown has changed since the 2007 traffic light system upgrade, told Stabroek News in a recent interview that while the study started at the Camp and Regent streets junction, there will be a city wide study in a phased out approach during this year. He explained that the ministry’s idea is to start its study with key junctions, such as Vlissingen Road and Regent Street, Vlissingen Road and Sandy Babb Street, as well as Regent Street and the Avenue of the Republic, so that the traffic signals could be reconfigured to deal with the current traffic.
“They need to be well synchronised, optimised, so that they can facilitate the best possible traffic movements,” Thompson said, while noting that the traffic movement from 2007 to now has changed.
He estimated that about 10,000 more vehicles a year have been added to the national fleet. “So the way people use the streets has evolved so to speak,” he said. “That is why an updated study was needed.”
Thompson explained that the Camp and Regent streets study resulted from the ministry’s observations of the huge buildup of traffic at the intersection during what he described as peak times, including holidays such as Christmas and Mashramani. He said the study’s goal was investigating what might be a good solution to alleviate the traffic problem at the intersection.
The first point of the study was to understand the traffic dynamic and this involved manual counts on all movements, including left and right turning movements, daily within a 12-hour period from 7am to 7pm.
The counts, which were recorded by between six and eight persons, were then imputed on a graph and used in a traffic software that models and simulates junction movements. The software identifies any problem with the subject junction and then solves it.
Thompson said the junction analysis revealed that if some movements, such as right turns, were restricted, the flow of traffic could be improved. He noted that the ministry looked at the turning movements—from Camp onto Regent Street and from Regent onto Camp Street—and it discovered that right turning movements were the fewest. The right turning movement from Camp onto Regent Street accounted for 3.2% of the 15,130 traffic movements for each day, while the right turning movement from Regent onto Camp Streets accounted for 2.9%.
The ministry also did a data analysis with the help of graduates from Ryerson University in Toronto Canada.
A traffic simulation done using a traffic analysis software, called Synchro, revealed that with the existing conditions, the level of service at the intersection was graded ‘F’ as denoted by the United States’ Transport Research Board’s Highway Capacity Manual.
Based on the manual, traffic movements at the intersection were providing a minimum level of service. Thompson said the proposed restriction on some right turn movements, save for right turns from Regent onto Camp Streets, would improve the level of service to a ‘D’ and delays at the junction could be reduced from 94.5 seconds to 59.5 seconds. He said that to further optimise movements at the junction, with the restriction of right turning movements and the creation of a slip lane to allow left turning movements when there are opposing flows, would bring up the level of service to a ‘C’ grade and delays would be reduced to 31.4 seconds.
However, Thompson stated that the ministry could not just implement the changes and it would seek to sensitise the public and ensure signs were in place for drivers.
Thompson also said that given the challenges of manual analysis, the ministry is procuring a software package called VisSim, which does traffic modeling and micro simulation.
He said the software could do traffic network analysis and provide the ministry with a better understanding of whether solutions would have negative spin off effects up and down flow streams. He added that the ministry is also acquiring special cameras equipped to do video data collection.
Those cameras are capable of recording up to 40 hours of data of traffic movements, and according to Thompson, they would be mounted for studies. That, he opined, was a better proposition, than having data collected manually.
