Safety issues at U turns

U Turns

U turns are considered as the least preferred traffic management activity due to the extensive inconveniences than the advantages and potential safety threats.U turn means change in direction of flow of vehicles from one direction with or without proper signal, to opposite direction, which create more complex issues. While taking U turns the vehicle making crossing conflicts with on coming traffic in the first lane and merging conflict probably on the second lane,depending upon the length of vehicle in addition to the merging as well as diverging conflicts.

Impact of U Turns

When a moving vehicle changes its direction of movement ,the vehicle itself stalled in the moving lane at first.This  incidence itself creates lot of inconvenience to multiple users mainly drivers  of others vehicles present at that area.Driver of the following vehicle or vehicles are the first affected users.If the any of the following vehicle driver is confronting with slight  distraction of mind,as it happens often when vehicles moves in convoy manner,  it may lead to minor or major incidents.
Entry of the vehicle ,which intends to take  U turn,into the opposite track will be a quick one.The drivers in the opposite lane of path of moving vehicle,where the  U taking vehicle is merging in to, may not anticipate such obstructions normally.These incidence pose serious threats to the safety of road users. The impact of  of U turn will be extensive as it affect the traffic on the particular area.And every thing will be more worse if the on coming vehicle is at a speed above 40 km ph. The risk chances at U turns are increasing when vision of drivers are obstructed .

Forced U turn 

Such turns are introduced as a part of traffic management In big cities .We have seen such turns at various part of our cities or town or at busy junctions. The number of vehicles plying are very high especially during peak hours of traffic. In such situation authorities Forced to implement certain measures with the object to reduce traffic congestion. U turns are widely used traffic controlling measures in our cities especially at busy road intersections.By introducing U turns ,the entire traffic take some forced deviations , from the point of congestion to a point little away from the junction.In theoretic terms, crossing conflicts are avoided by means of  deviations. The Number of conflicts comes up to a minimum of four numbers including ,merging conflicts and crossing conflicts,depends upon the direction of move.But when the vehicle take U turns a combination of  crossing  and merging conflicts enters to the scene.This situation will be quite under control during off peak hours.But during peak hours this will become more complex.Reduction in traffic congestion are witnessing by this kind of traffic modification.In fact these reduction is not due to the deviation but the vehicles are kept on moving at a distance around 300 to 400 mtrs or more ,depending upon the type of junctions.The vehicles are accommodated in this length instead of keeping halt at junctions.

Signal Controlled Junctions

In the signal controlled traffic management system , the flow of traffic from all the other direction except one direction is closed ,at a measured point of time.At the same time vehicle flow from other directions will be closed .That means chances of crossing conflicts are theoretically zero and the chances of accident is also very less.In the case of deviation and U turn combination,vehicles from all directions are always in motion and at certain segments withing the area are highly congested with the irregular flow of vehicles to and from multiple directions.

U turns are potentially dangerous.In a junction there are various kinds of conflicts between moving traffic at different paths.In the case of a U turn controlled traffic management,all the conflicts are live and present along with the moving vehicles.The deviating vehicle is forced to take the merging conflict at first ,in case of four lane traffic and then crossing conflict on the second lane,followed by serious of conflicts on the opposite lanes.In each conflicts the safety has to be compromised.The situation is getting more complicated if any of the vehicle is at excess speed and driver adopt rash and negligent driving manners.The same will be the effect if stage carriage bus drivers approach the scene.

Obstruction to Vision in U turns

Obstruction to the vision of drivers,while taking  U turns,increases the risk chances.Better vision of  road,especially the oncoming traffic movement in the opposite side is very essential for U turns.Other wise the sudden entry will create lot of confusions to the drivers of on coming vehicle ,in the merging lane,which will not be an anticipated movement by the drivers in that lane and which may lead to serious mishaps.This problem is very acute in Kochi City after the construction of KOCHI METRO.The huge pillars situated at equidistant create greater visibility issues to the vehicles taking U turns.In addition to that as a part of modification several free entry to the highway were closed and the vehicles coming from that opening are forced to take U turn.Both these issues are raising the  threat factors present at these spots.

Road Accident Rate At U Turns

There are two distinct reasons for U turns in our cities.The first one is normal U turns whereas the second one is forced  U turns as a part of traffic deviation,as we discussed above.The rate of road accidents are very high in the second instances,even though specific data is not available with SCRB. One of the traffic survey conducted privately to analyse the situation states that there are 10 to 15 accident chances are developing in each one hour of traffic,and which will climb during peak hours.The measured factor for such increased tendency of road incidence at  Forced U turns are the increased flow of traffic and non disciplined movement of vehicles at these junction.Two wheeler are the high risk elements followed by motor cars.Fortunately actual accidents scenes are comparatively low when compared to actual threat instances at each U turns.It is fact that each of the conflicts especially crossing conflicts,poses serious threat to the human life.In the  cases o U Turns,number of conflicts are increased.

In one of the reported case of fatal accident at Vyttila ,U trun ,a stage carriage bus ,which was proceeding at the 3rd lane ,attempted a U trun to the Right side,ignoring other vehicles on second and first lane.Unfortunately a motor car ,which was also proceeding at the same direction,hit against the bus and lost control and rammed in to a motorcar which was plying in the opposite direction.One of the passenger dies and two other including driver severely injured.

BE Extra Cautious at U turns

The only simple advise that can be given to all road users is be cautious at U Turns,since they are poising a new threat to the safety of road users.Low level Visibility,sudden  attempt to merge to opposite traffic etc are the reason for increased threat level in U Turns.
The Metro pillars are the new threat of this era.Low level of visibility is the main cause of accident at  these spots.