EMBARQ China helps the city of Jinan increase ridership on bus rapid transit (BRT)
In the past five years, China has become the world’s fastest growing market for bus rapid transit (BRT). Today there are 17 BRT systems in China that serve 2.3 million people – the majority of these were built after 2008. Furthermore, China aims to build a total of 5,000 km of BRT by 2020, a fivefold increase form today. This BRT expansion will help Chinese cities – already home to the world’s largest urban population – provide safe, efficient, and environmentally friendly mobility to the country’s expected 350 million new urban residents by 2030.
The city of Jinan, home to 2.8 million people, has one of the China’s largest BRT systems, boasting four corridors serving 220,000 passengers each day. Still, this is less than 6% of the city’s population. EMBARQ China has partnered with the city to increase ridership and improve the efficiency of Jinan’s primary mode of sustainable mass transport.
Last month, the EMBARQ China team met with the Jinan Urban Transportation Research Center and the Jinan Traffic Police Detachment, the government agency responsible for operating and managing traffic signals in China, to reduce delays for the BRT buses at signalized intersections. Although a seemingly small change, making buses a priority at intersections emphasizes further saves riders travel time, reinforces the city’s emphasis on sustainable transport, and encourages use of the BRT system.
Increasing efficiency, increasing interest
A contributing factor to Jinan’s relatively low ridership is that the BRT buses face long waits at signalized intersections (those with stoplights), which negates one of the great selling points of BRT: travel time savings. This system provides little incentive for the city’s residents to choose sustainable mass transport. As part of a larger effort to increase efficiency for the BRT system overall, EMBARQ China is exploring measures to reduce delays for BRT buses at signalized intersections.
EMBARQ China’s first step in determining the potential effectiveness of signal prioritization was to conduct a field survey. The field survey indicated that long cycle lengths – or how long it takes the light to turn at an intersection – were indeed a large contributing factor to BRT delays. At some major intersections, the wait was over three minutes. Other contributing factors, such as volume that exceeds the BRT’s current capacity, play a lesser role, but cycle length directly affects intersection capacity and delays, and is also one of the few factors that the system administrators can control.
Link between cycle length and capacity
Longer cycle lengths can increase capacity, but only marginally, especially when cycle length exceeds 120 seconds. EMBARQ China found that shorter cycle lengths were more likely to result in reduced delays. Theoretically, when cycle length increases from 150 seconds to 160 seconds, the intersection capacity will only increase by 80 vehicles per hour, while the delay imposed on each vehicle will be three more seconds. When considering the BRT’s 220,000 daily passengers, these three seconds add up to create significant delays.
For example, Line 1 of Jinan’s BRT has an average daily ridership of about 70,000 passengers. A three second delay would impose a total of 58.3 hours delay each day at one intersection, create significant economic losses, not to mention the stress it adds to the daily commute for thousands of riders. In sum, the gains in capacity from making buses wait at intersections is negated by the delays it creates, which discourages Jinan’s residents from using the city’s BRT.
Now, EMBARQ China will work with Jinan’s transport department to carefully choose the appropriate cycle length that will minimize overall delays at intersections. These fine adjustments will reshape Jinan’s transport network to be more environmentally, socially, and financially sustainable, and provide viable alternatives to the car for one of the world’s fastest growing cities.