All About Green

The Congested City and Its Intensified Miasma

Original Chinese article published on Sing Tao Daily “Green Forum” (8 April, 2019)
Author: Green Power
Traffic congestion caused by crowded vehicles

The full commissioning of Central-Wan Chai Bypass Tunnel has again brought the traffic congestion issue in Hong Kong into focus. Over the months, traffic jams remained a grave concern in the discussions of “ERP Pilot Scheme in Central Core District” proposal and “Toll Adjustment Proposal for the Three Road Harbour Crossings”. The phenomenon of lines of vehicles choking up the roads is never alien to Hongkongers. In fact, environmental concerns have always been taken out of the checklist, leaving the air pollution issue as a blame game.

Half of the Journeys Through the Cross Harbour Tunnels are Taken by Private Cars

Every day, over 600,000 local passenger journeys are made through cross-harbour tunnels in Hong Kong. There are over 500,000 commuters taking harbour tunnels from Kowloon and the New Territories to Hong Kong Island, while over 140,000 citizens taking trips in the other direction, as revealed in the 2016 Population By-census. The traffic dilemma remains insoluble, despite the fact that the ratio of daily passengers commuting by public transport has already gone up to 90%. Is it still appropriate to blame the insufficiency of cross harbour transport?

Private car patronage in the three tunnels accounts for 50% of the total number of vehicles, which is six times greater than the figures for buses and minibuses (around 7%). For this reason, the 10% of non-public transport users are crucial for breaking the gridlock.

Exhaust pipe of private car

Apart from sabotaging labour hours, traffic congestion plays havoc with air quality. The impact of air pollutant emissions by diesel vehicles during traffic jams was studied by a group of English researchers in 2017. Slashing the speed limit from 20km/h to 10km/h in London, nitrogen oxide emissions by Euro VI bus escalated 50%, while the emissions from light diesel vehicles increased by less than 30%. The study demonstrated that increased vehicular queueing time has a greater impact with new generation vehicles. In other words, the slower the bus drivers drive, the greater the societal costs we suffer from, ie the delayed journeys as well as the dirtier air. Therefore, ensuring smoother travel for buses, the highest capacity road vehicles, is of supreme importance to alleviate air pollution on the roads. One method is to restrict the patronage of private cars in congested areas.

Transport strategies of Hong Kong have been weighted towards meeting the traffic demand, yet rarely manage the demand in a proactive manner. The congestion problem in Central and Western District, alias the "CBD" of Hong Kong, could hardly be resolved simply by constructing more roads or carparks. Without a doubt, reduction of total vehicle numbers could be the best thing since sliced bread. For example, restricting the use of specific parts of roads or tunnels by vehicles with lower transport effectiveness (e.g. private cars) or which are less environmentally friendly. If this measure is too extreme, an easier way out would be increasing tunnel tolls or electronic road pricing for specific roads.

Scrap Vehicles which Fail Environmental Standards

Phrasing out vehicles which fail the emissions standards is another practical measure. In the past, older heavy goods vehicles were forced or encouraged to retire, although the solution yielded less results than expected. To further control the rising number of private cars, the government has increased the first registration fee or related taxes from time to time. However, demand for private cars recovers again and again. In the past 10 years, the ratio of private car owners has risen from 55 cars to 75 cars per 1,000 Hong Kong residents, which is a 36% increase. Looking at the total length of traffic roads per registered vehicles, the average traffic road length for a vehicle is less than 3 metres – even shorter than an average car length! How could anyone find the situation acceptable?

More than a mere financial concern, breaking the traffic logjam means not letting pollutants go unchecked. The aggravated heat island effect and carbon emissions threaten our lives and environment. Therefore, the government should take prompt steps to bring an end to traffic problems.