City Traffic Planner
-- A Member of REC Professional Services Group
Quality Professional Services
Tunnel Congestion
Hong Kong has three cross-harbor tunnels and the central one is always blamed of heavy congestion.
There are many reasons behind this issue and we will look at this particular problem in another section in this site.
One of the contributing factors is the design of toll booths, which is deemed to be a restriction in the physical flow of traffic causing the bottlenecks.
Fluctuations in Normal Traffic
Day-to-day fluctuations in demand results in some days with very high traffic volumes and some days with comparatively lower traffic volumes.
When this varying demand and thus traffic volumes are superimposed on a system with a fixed capacity, it results in variable and thus unreliable commute times.
Road Works
Road work is initiated to repair or improve existing roads, with an aim to reduce future congestion. Road work initiated by utility companies is also necessary to repair or install pipes and cables.
These road works usually result in reduced lane capacity (number or width of travel lanes), lane shifts, lane diversions, reduction, or elimination of shoulders, temporary roadway closures, slowing traffic and causing periodic standstills.
Congestion Factors
There are many reasons for congestion. Some are due to design of roads and traffic light system, while some are due to human behaviour or natural environment. City Traffic Planner here presents with 8 most prominent factors causing traffic congestion.
Traffic Signal Timing
Intermittent disruption of traffic flow by poorly timed signals contributes to congestion and travel time variability.
Non-real-time signal timing of traffic lights leads to inappropriate short waiting time of certain busiest lanes.
Physical Capacity
Each road has a certain and fixed physical capacity, which means each road has a maximum amount of traffic that can be handled.
Capacity is determined by a number of factors: the number and width of lanes and shoulders; merge areas at interchanges; and roadway alignment.
Incorrect design of road to fit existing traffic volume leads to bottleneck overfill and thus traffic congestion.
Traffic Incidents
Non-recurrent events, such as accidents or abandoned cars, cause a restriction of roadway capacity.
Accidents are usually caused by inattentive drivers, equipment failure or speeding, and the subsequent blocking of the road results in slow traffic and standstills.
High Demand Zones
There are certain areas with particularly high traffic volume due to reasons such a robust economic activity.
Example in Hong Kong is the Central and Admiralty in the Hong Kong Island. These areas are much busier than others because of high working populations and economic activity there.
Many private car drivers get into these areas for work. And many public transport routes go through them. With limited capacity, traffic often builds up quickly and congestion is resulted.
Weather
Weather events, including heavy rain and storms, can significantly reduce road capacities and result in traffic congestion.
Drivers are also more likely to drive more slowly or to abandon their cars during serious weather events.
The effect of weather on traffic congestion is particularly prominent in the early times of a weather event since people are rushing back to their home at the same time. But in the later times of a weather event, the flow is more efficient since there are far fewer vehicles on the road.