Charlottetown, PEI is a classic tourist town. The Capital, and largest city on Prince Edward Island in Eastern Canada has a population of just over 35,000 but it sees a massive influx of tourists each summer, bringing upwards of one million overnight stays to the city. To put that in perspective, residents in Charlottetown effectively deal with an almost 3000% increase in traffic volume, when visitors flock to the city in the summer months. While it’s a huge boost for tourism, the introduction of so many additional vehicles to the city center each summer can cause massive traffic headaches for residents and tourists alike. The increase in traffic also has an obvious effect on city planners, who struggle with finding options to ease the congestion with their limited resources.
As part of a pilot project to address the traffic issues, four intersections along N River Rd. from Belvedere Ave. to Capital Dr. were equipped with Miovision hardware to gather data. This particular section of the corridor in question was identified as a “bottleneck” which, according to a news report, was causing a two-kilometer gridlock along the roadway during peak hours.
Using Miovision TrafficLink hardware and software, the team was able to gather and analyze data that uncovered a particularly congested PM peak in the Northbound (NB) direction. Drivers were taking an average of four times longer – amounting to a travel time between 10 to 15 minutes – to travel this particular stretch of the corridor, when compared with other hours throughout the day.
The data also showed that from a signal coordination perspective, progression was limited due to the free-mode operation of the intersections along the corridor, which meant that vehicle platoons could rarely travel the corridor without stopping.
Importantly, traffic demand was also measured and analyzed during the pilot, which uncovered some promising data. Continuous turning movement count data from Miovision SmartSense was gathered at the intersection of North River and Capital Dr. This data showed that the volume of vehicles in the “after” conditions were not only comparable with the “before” conditions – they were actually higher. This means that the corridor was performing better, even though vehicle volumes had actually increased.
Overall, just one week following the signal retiming, data has shown a 22% reduction in average travel times from 3 – 6 pm. The improvement is even more significant from 4 – 6 pm, with an approximately two-minute reduction in the median travel time,which translates into a 32% reduction. What’s more, none of the individual intersections along the corridor experienced a significant reduction in performance. In fact, the data shows a total of 6% reduction in the number of split failures on all movements along the corridor.
In addition to the travel time improvements, the successful retiming project resulted in the following savings for Charlottetown:
Estimated Total Vehicles Impacted (per year*) 1,380,000
Total Travel Time Savings (vehicle-min) 1,129,100
Total User Cost Savings** ($/year) $507,145
Total Emissions Savings (tons/year) 3772
Total Fuel Savings (liter/year) 167,268
Savings (liter/year), Estimated Total Savings ($/year) $555,110
All calculations done using formulas provided by the FHWA/IN/JTRP-2010 of the Joint Transportation Research Program.
*It is assumed that the savings will hold over 300 days per year.
**A $20 per hour user delay cost is assumed per person for passenger vehicles and a $100 per hour delay cost is assumed for freight vehicles. A 1.2 passengers per vehicle is considered.
Considering that signal timings are generally revisited every three years for a corridor, a total estimated value of $1,655,000 of savings is expected over three years.