Unsafe driving behaviour due to bad Junction design

Original Posted 2012-08-01

Update: 2013-04-23
Fatal accident at Deadly Junction of Clementi ave 3 and Commonwealth west ave.
It is very sad to learn that the “Deadly Junction” design has claim another victim, a 42 years old lady. This morning a 78 route bus turned left from Commonwealth West Ave into Clementi Ave 3, the lady was hit and drag for 5 meters before the bus stopped. (Find how they got California traffic ticket lawyers for hire to defend the case) . The accident site features the “Deadly Junction” design – big turning radius and pedestrian crossing is located right at the round. It was not clear if the “green man” was on when the lady cross the road. More info at “Stomp

Update: 2013-02-04
I was shocked to read that, with respect to what happen at Tampines tragic accident, the Vice-Chair of Singapore Road Safety Council, Prof Menon, still feels the current road system is OK and is the “most fair system for all road users to be able to share the time in which the green man is on and minimize delay.” It sounds to me like the few seconds of delays for motor cars is more important than the lives of the pedestrians. I serious hope LTA can review their road junction design and not wait for more tragic to happen.

Update: 2013-02-02
Photo: the aftermath of an accident involving two boys and a cement mixer in Tampines on Monday, 2013-02-28. The two brothers Donovan Yap, seven and Nigel, 13 were killed in the accident.

Junction with large turning radius is designed to facilitate fast moving cars to make a turn, without the need to slow down or stop. But this design makes it difficult for driver to watch out their surrounding while turning.

Following image is taken from an accident scene that a bus hit a school boy just crossing the junction.

The bus driver must be distracted while making the turn. His main attention is on the front and right, where cars from may turn into the same lane he is about to turn to. This check is essential to avoid front collision, a serious threat to his own safety. At the same time he need to watch out for pedestrians on his left, his vision is largely block by his own bus, while it is moving. Checking on front/right and rear/left simultaneously on the move is simply impossible for human being!
dangerous junction

From the pedestrian point of view, the boy need to check if the traffic light green man is on, which in front of him. While at the same time the bus is coming from behind (right). If the boy is not aware of the danger, he would feel confident to cross the road when the green man is on. He has a high chance of being hit by the motorist who is not watching 100% at his direction. Elderly and young kids are most vulnerable in this situation.
dangerous junction

Below are images relates to the Tampines accident site on 2013-02-02
View from the driver at the junction

Analysis of the risk factors

Proposed improvement to enhance safety and facilitate more efficient walking and cycling

The proposal is based on one safety principle and two human factors. The principle is:

Safety of road users is more important than speed.

To enhance safety we consider two human factors. First, human need time to anticipate and response. Second human eyes are able to look towards the front, at most a 120 degree span. The proposed design use a safety island to moderate the speed of motorists before they approach the junction. A driver has more time to response to any unexpected situation if he/she approaches the junction at a slower speed. Even if accident happen, the severity of the injury is significantly lower (WHO fact sheet- car speed and safety). “hump” zebra crossing is positioned not at the turn, but before and after the turn. The road and the zebra crossing is perpendicular to each other, such that both motorists and pedestrians can see each other easily without turning their heads. The safety island provide a mid-point safe stop for pedestrian to wait for the clearing of the next car lane before they complete the crossing.
The functioning of the “hump” zebra cross is illustrate in another post, it is shown that such crossing is not only safer, but it is more time efficient for both pedestrians and motorists.

Certainly the above is not the only improvement design. There are many good examples to be learn from countries like the Netherlands, or even Japan where population and traffic density is comparable to Singapore.

Related articles:
Safe driving and walking behavior guided by good road design

5 thoughts on “Unsafe driving behaviour due to bad Junction design

  1. Pingback: Don’t blame the user if the design is bad | Love cycling in Singapore

  2. Pingback: Update on “Deadly junction” design | Love cycling in Singapore

  3. Pingback: Bicycle friendly city – What I saw when cycling in Tokyo? | Love cycling in Singapore

  4. Francis

    Accessibility of any network is defined by the weakest link. Currently traffic intersection where motorist and non-motorist meets, are the most dangerous spot of any cycling and network. Improve these traffic intersection will enhance the usability of the entire network. The Dutch know this and has been systematically improving their traffic intersection over decades: https://bicycledutch.wordpress.com/2014/02/23/junction-design-in-the-netherlands/

  5. Pingback: How to make traffic intersection safe – a key component of bicycle network | Love cycling in Singapore

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