The Catalonian capital is implementing ambitious plans for a next-generation bus rapid transit network based on research by ITS Berkeley's Carlos Daganzo
SPRING 2010 — On February 23, 2010, the City of Barcelona, Spain, publicly announced ambitious plans to implement a next-generation, bus rapid transit (BRT) network in January 2011. The design of the cutting-edge new system is based on research by Carlos Daganzo, University of California, Berkeley professor of Civil and Environmental Engineering and Director of the UC
Berkeley Center for Future Urban Transport, a Volvo Center of Excellence, which is housed at Berkeley’s Institute of Transportation Studies. (Pictured above: A hybrid-electric bus destined for the new system.)
The goal of the new system, called RetBus, is to cover the whole city with fast, high-frequency lines that allow people to travel anywhere in the city quickly and reliably.
The Volvo Center collaborated on the plans with the Center for Transport Innovation (CENIT), a not-for-profit research center headed by UC Berkeley alumnus F. Robusté, also in Barcelona; and two key public agencies — Transportes Metropolitanos de Barcelona (TMB), Barcelona’s public transportation agency, which would run the BRT system, and Ajuntament de Barcelona (ADB), City Hall, which oversees the traffic regulations and traffic signals that would need to be adjusted to make room for the buses.
"Being a native of Barcelona, it was especially meaningful for me to make a contribution to this project,” said Daganzo (pictured left), who conceived the advanced network system and led the scientific research effort underlying the plan development.
At the February press conference in Barcelona, directors of TMB and ADB presented the general plan, and Daganzo explained its technical rationale. The two directors announced that they hope to begin rolling out two lines — one north-south, one east-west — in about a year. The plan was later amended to aim for opening three lines in 2011.
The implementation would only require new operating protocols; minimal changes to the infrastructure and to the fleet of existing buses would be needed. Once glitches on these initial test lines are worked out, the rest of the system can be rolled out quickly. If work is begun within a few months, organizers believe they can have the entire system rolled out by the end of 2012.
Spanish News Headlines
Spanish-language news coverage provides more details:
Old versus new
Currently, Barcelona’s city buses have an average speed of 11.7 kilometers per hour (km/hr), including stops to pick up passengers. The buses travel so slowly because they are hindered by automobile traffic and by the short distances between passenger stops. The new system mitigates these problems and promises average speeds of at least 15 km/hr. Daganzo believes it will easily exceed this target, probably approaching 20 km/hr.
The new service will cover the entire city and will be well connected to all key interurban travel stations, providing a complete urban mobility solution for Barcelona’s residents.
“Most bus systems have very good spatial coverage — with many lines and many stops — so you don’t have to walk very far to a bus stop,” Daganzo said in a recent interview with The Berkeley Transportation Letter. The trade-off, he said, is poor temporal coverage, because with its finite resources (buses), the bus agency can only allocate a few buses to each line. As a result, bus users have to wait a long time for the bus to arrive, and then travel slowly while the bus makes all those stops along the way. So a typical trip takes a long time.
RetBus, which translates to “net bus,” a play on words alluding to both a network and a widely cast fishing net, will be different from the status quo: the system design sacrifices spatial coverage slightly, by placing stops further apart than in a conventional bus system, but not as far as in Barcelona’s Metro system. It compensates by improving temporal coverage drastically, offering three- to four-minute service intervals everywhere in the network, together with fast in-vehicle travel.
The network shape has also been optimized to ensure that most trips can take place without significant detours and at most one transfer.
Daganzo says this system structure adds benefits through simplifications that make the system both efficient and easy to use. There are fewer bus lines than in the current system and they are organized in an easy-to-understand way. Thus, riders can keep the few key lines in their head rather than needing multiple maps and schedules.
Buses can move faster because they don’t have to stop all the time and the bus company has fewer routes to cover so it can provide more frequent service with the same — or potentially even smaller — fleet.
The main tradeoff is a slightly longer distance to walk to the bus stop, but the planners envision an average door-to-door travel that is competitive with the automobile.
Technology and design
The overall vision for the system is that
- Every citizen should be less than three blocks (about 350 meters) away from a bus stop;
- Frequency should be between three and five minutes on major corridors, and all on the surface rather than underground; buses will be controlled to ensure that these service intervals stay reliable.
- Transfers will be limited to one for a vast majority of trips;
- Buses will go faster than the current system—between 15-20 km/hour, including stops; and
- The network will be simple and easy to understand—based on a simple numbered grid.
But the key is not just in the system plan and reliable operation. For Retbus to be successful, buses must not be slowed down by traffic; thus, new methods to get traffic out of the way will need to be implemented. For example, ADB is considering applying the Volvo Center’s “moving cocoon” idea, which allows cars and taxis to use bus lanes when the bus is not there; but when the bus is there, other traffic must get out of the way.
'In the central area, you have the grid, but on the periphery, you have radial branching, so you are deploying your resources in the most economical way.'
“Basically, this method treats buses as if they were ambulances,” Daganzo says, adding that this element of the plan gives buses the right of way, while keeping the bus company and the city from being at odds over limiting the use of a traffic lane—a conflict that has slowed BRT progress in other cities.
To enforce this and other bus priority laws, buses would have cameras to record offenders, who would be ticketed. Enforcement would also be supported by stepped up officer patrols on the ground and steep fines.
If Barcelona meets its phase-one implementation goals, the city’s journey from plans to a new system would be one of record speed. How did it happen so quickly?
Against a backdrop of political unpopularity for the governing party, Daganzo was invited to present his transit research at CENIT (pictured below) during his 2008 sabbatical. Representatives from TMB and ADB were guests at the presentation.
After the talk the agencies were intrigued. A discussion of their existing planning for a single BRT line led to more in-depth talks about a full system that would require little new infrastructure. City Hall got excited about this possibility, and the government saw an opportunity for a much-needed public success. The three organizations teamed up with Daganzo and ITS Berkeley’s Volvo Center to develop a plan with a sound scientific basis.
The chief goals of the project were to expand the metropolitan area served and to apply technologies that can make buses go faster. But city planners and architects are dominant voices in this famously aesthetics-conscious city, so using virtual methods rather than physical infrastructure was also important.
“Barcelona is city that cares deeply about art and architecture,” said Daganzo. “A more intrusive system would simply never be built, but because this system is based mainly on 'soft' technology and traffic management, it found support.”
Most public transport systems are based on either a radial or grid arrangement. “This is a hybrid system that combines the best aspects of both of those approaches,” said Daganzo, who added that the hybrid approach was optimized for Barcelona’s particular geographic challenges. “In the central area, you have the grid, but on the periphery, you have radial branching, so you are deploying your resources in the most economical way,” Daganzo explained.
This hybrid approach, along with the technology and enforcement policies that support the system, is new science, so other cities, along with the transportation community at large, will be watching to see how well it works, said Daganzo. “If Barcelona does it right, it will be a model that others can copy.”
For more information on design: Daganzo (2010)
For more information on the cocoon concept: Eichler and Daganzo (2008)