Reducing road traffic in large cities is a better option than raising road capacity
As the government takes small steps for a giant leap into smart cities, a stopover could be made to devise smart road transport in large cities. Smart road transport can also save investment in road infrastructure and transport systems.
Individual road transport is a key pillar of the transport system in cities, but its proliferation chokes roads and residents. Congestion makes road infrastructure inefficient and causes pollution economic loss.
The fight against congestion is now universal. Essentially there are two ways to battle congestion; reduce road traffic, or enhance road capacity. Of this, the better option is to reduce road traffic through technology and policy interventions.
One most efficient method to reduce congestion, according to a new OECD publication titled The Metropolitan Century, is the introduction of a congestion charge. Congestion charges ensure that motorists driving in cities pay a compensation for the negative consequences that this has for residents and other road users. It also discourages some potential road users from driving and thereby reduces congestion.
Congestion charges often face fierce political resistance, but have been successfully introduced in several major cities like London, Singapore, Milan and Stockholm in recent years. Still, the measure has its limit. Despite London’s congestion charge of GBP 11.50 per day, it is still the ninth most congested city in Europe with an average delay of 36 minutes per peak hour of driving. The political backlash can be mitigated if congestion charges are implemented in a revenue-neutral way with the extra funds being used to reduce other taxes or fees.
Congestion charges can be varied according to the time that a car enters a city or the amount of pollution it emits. In Stockholm, prices vary over time and are highest during the peak rush hour, but are completely free at night. In Milan, no charges are applied to low-emission vehicles, whereas high-emission vehicles are charged up to 10 euros a day.
Much more widespread than congestion charges are parking charges. Politically, it can be easier to increase the existing parking charges than to introduce congestion charges. Besides congestion charges and parking charges, local governments can take other measures to limit congestion.
Technological innovations, for example, can increase the traffic volume that can operate on existing road infrastructure. Adaptive traffic flow control systems that regulate traffic lights, open and close lanes, adjust speed limits and change direction signs are already used in many cities. They are efficient measures to increase the road capacity and reduce congestion. They are also much more cost effective than the construction of new roads.
In Frankfurt, for example, traffic control centres steer traffic on all major roads in and around the city. Traffic flows are monitored by cameras and sensors and reported to the control centres. Most traffic lights in Frankfurt are connected to a control centre and can respond flexibly to traffic volumes by modifying the timing of green phases.
Besides ensuring smoother traffic flows, the traffic lights also limit the inflow of vehicles into the city if the maximum road capacity is reached. Thus, traffic jams occur predominantly outside the city where their negative consequences (such as air pollution) are less pronounced. Furthermore, the traffic lights automatically grant priority to buses and trams.
Throughout the city of Frankfurt, the number of free parking spaces in different neighbourhoods is displayed on signs to prevent motorists from driving around in search of a parking spot. On main routes into the city, variable direction signs are used to steer traffic flows in case of large public events and traffic accidents. On motorways around Frankfurt, it is possible to remotely open the emergency lane for regular traffic in case of high traffic volumes and to close it in case of accidents or breakdowns.
Smart technologies are paving the way for other innovations related to transport in many other cities. San Francisco, for example, is pioneering smart parking meters that adapt prices to demand. When available parking spots are scarce, prices increase to discourage people from driving into the city centre. Similarly, Madrid has introduced smart parking meters that charge varying prices according to the emissions of a car.
Low-tech solutions still offer great potential in many cities to reduce congestion. The simplest solution is to encourage people to carpool. Currently, large majorities of people commute alone to work. In the US, for example, only 16% of commuters who commute by car share it with another person. People can best be encouraged to carpool by direct incentives, such as reduced tolls on toll roads.
A solution that is found common in the US is high-occupancy vehicle lanes. These lanes are reserved for cars with more than one occupant. High-occupancy lanes make carpooling attractive because they are less congested and allow for faster commutes. This is something that can be tried in India to encourage car pooling, with practically no investment. The fast lane can be marked aside for high-occupancy cars.
Investment in smart road transport in large cities will have the advantage of quick impact and high visibility for the government.