Shanghai night sky
Last week my city mobility colleague, Magnus Broback, made a presentation at a seminar about public transportation in Shanghai and we took the opportunity to visit some of our contacts while visiting. As an old city that is still growing, Shanghai struggles to find a balance between efficient public transportation and city planning.
The old part of the city is especially crowded with all types of vehicles running in the streets. The traffic moves slowly and becomes disorderly in the crossings. However, in some areas main corridors have been defined, which makes the pace quicker with traffic lights controlling the flow. In these sections buses are prioritized and often given the priority of way in separate lanes.
One of the thousands of Volvo/Sunwin buses in Shanghai
On small roads close to the city center, buses have little priority and frequently get stuck between cars. This leads to low speed leads and fewer passengers, which, in turn, results to lower priority given to the buses.
How can a city find methods to prioritize the street space for the benefit of the society?
If we compare three cars to one 12m bus, they actually occupy about the same space on the road, 35 sqm. Cars carry on average 6 people and the bus carries 30 people. This is not only a question about congestion: the time lost in traffic per person should be valued equally.
How can society find simple principles to compare the right to priority for different road users?
Value of time for travel: in literature we can find different standards for defining the value of travel time. For travel to work, I find it is logical to use the GDP per capita per working hour as a base. This gives us a measure that can be locally adapted for each city, but still easy to understand and use.
In the table below I compare the hourly cost for the number of persons occupying 35 square meters of street space.
Table: Value of travel time
|All costs in $
||Cost per hour
||Cost per hour
*global rough average
The assumption is that the hourly cost is defined by GDP per working hour in each country. The consequence is that the value of a street occupied by frequent bus traffic is about five times higher than the value for a street of cars, assuming that the capacity difference is used fully. I see a counter in front of me where the cost is ticking constantly.
Now, the interesting question arises…
If a car user wants to get prioritized what is a reasonable price for the street space from the perspective of the society?
I would reason that the difference in time-value is one important factor. The car users need to buy the time from alternative use and, at the same time, transportation capacity needs to be taken into account.
The value of time is frequently used to compare priority of new investments. The question is whether this line of thought can be used to prioritize road space for different means of transportation and for different times of the day.
Is the value of time for different means of transportation a number that is useful for making educated decisions on using prioritized lanes and planning infrastructure?
On Wednesday evening, my travel companion for this journey, Magnus Broback, and I decided to have dinner in the city. The bus stop outside the lobby of the hotel was crowded with two buses running different routes, clearly marked by Arabic numbers 184 and 642.
Most people walked to the bus stop from the surrounding residential areas, while others came by bike. Seemingly a constant flow of passengers embarked the buses. At this time of the day, nobody seemed to exit the bus at our stop.
When passing the metro station earlier the same day, we saw a bus terminus with lots of routes delivering travelers to the subway. We assumed that at least one of the buses would take us the 3548 meters (the accuracy delivered by my nerdy habit of logging travels by GPS) to the nearest metro station. However, all the signs at the bus stop were in Mandarin, which neither of us can speak or read. We decided to ask the concierge for help.
The following conversation took place at the desk in the lobby of the hotel:
Me: Which bus can take us to the metro station?
The receptionist: You want to go to the metro station? Where are you heading?
Magnus: We are going to the city center.
The receptionist: I will call you a taxi.
Me: But, we want to take the bus and the subway.
The receptionist: The taxi can take you to the metro station.
Magnus: Is it bus route 184 or 642 that stops at the Technology and Science Museum station?
The receptionist: No you cannot take the bus.
The receptionist: You will get lost.
We left the hotel without further discussion. It was getting dark, so we decided to take a risk. We decided to jump on the first bus that arrived, bus 184. It was most user-friendly. A lady, with a small red flag that she stuck out of the window to show her location, was selling tickets on-board the bus.
The price was 1 Yuan each, which was very cheap. As the bus was getting more crowded, the lady moved around to check the tickets, including the digital tickets found on smart phones, which were used by most. During our last leg, the bus was getting too crowded for moving around and we helped by passing money and tickets between new travelers entering the bus and the lady with the red flag. We followed the bus path street-by-street and found that it took us to the station after 4 stops along the way.
The moral of this story has many implications. Buses in general are perceived as complicated. The large number of routes makes few people aware of which route is heading for which terminus. There is a feeling that the bus may escape the route and not head for the right stop. We people in the bus business have a lot of work to do to make the systems more transparent.