Road Safety News
 

Removing white lines can reduce speeds: TfL

Tuesday 19th August 2014

A trial carried out by Transport for London (TfL) on three stretches of road showed that removing central white lines resulted in a reduction in vehicle speeds.

Explaining the results, TfL suggests that “centre line removal introduces an element of uncertainty which is reflected in lower speeds”.

TfL says that most traffic engineers prescribe white lines “by default without questioning the necessity”. Its study set out to “challenge this assumption” by investigating the effect of not reinstating central markings following resurfacing works.

TfL points to an earlier study by Wiltshire County Council which found that not reinstating white lines led to a reduction in injury collisions and traffic speeds, and to referenced research by TRL which concluded that there are safety benefits to be gained by removing centrelines in 30 mph zones.

TfL reviewed the markings along three routes scheduled for resurfacing, and the white lines/hatching were not reinstated following the works. Before and after speed surveys were carried out at each site to monitor the effect on speed, and at one site a section of centre lines/hatching was retained as a control.

The results showed a “statistically significant” reduction in vehicle speeds - by a minimum of 5.4mph and maximum of 8.6mph - as a result of removing central markings.

Explaining the results, TfL suggests that that centre lines “can provide a psychological sense of confidence to drivers that no vehicles will encroach on ‘their’ side of the road”. It also says “there can also be a tendency for some drivers to position their vehicles close to a white line regardless of the traffic conditions, believing it is their ‘right’ to be in this position”.

The study concludes that “centre line removal introduces an element of uncertainty which is reflected in lower speeds”.

TfL points out that not all roads would be suitable for removing central markings, particularly where the markings highlight a particular hazard.

 

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This was not a complete trial of the the removal of road markings as can be clearly seen by the before and after pictures. To be a "true" trial of the no white line safer driving theory the cycle lane should've been removed. Drivers are quite clearly taking their road position from the white line on their nearside, and also to some extent from the clearly visible ridge at the centre of the road.

In the UK the first one was at Sutton Coldfield at Maney Corner in 1921 and it was so successful it was adopted nationally.

The concept of roads being "shared space" is fine in back streets and the suburbs but not on major roads.

Perhaps it is worth remembering that the first white lines were painted by hand by Doctor June McCarroll on America route 99 in 1917 after her model T was forced off the road by a truck hogging the crown of the road in Cochella Valley.
Bill Dean Oldham

Agree (0) | Disagree (0)
0

A centre line clearly indicates your half of the road, crossing it puts the onus on you (say for overtaking a cyclist) and does stop drivers wandering over your side of the road on corners. Readers of this website might not need them, but the general public do!
Also they can be very useful in thick fog.
Terry hudson, Kent

Agree (9) | Disagree (8)
+1

Having read the report which has its basis in fact to prove that lower speeds of motor vehicles are safer for pedal cycles. I took interest in the single control area where after relaying the road surface the lines were re-introduced and the result was an increase in traffic speed (though I presume that would in fact be a more normal return to that speed) of some 4.5mph making it basically 35 mph. It is then that we get the assessed differential of 7/8mph assuming all the three roads would have had traffic travelling at that greater speed of 35mph. Is this the basis of scientific trials? I leave you to draw your own conclusions.
bob craven Lancs

Agree (3) | Disagree (1)
+2

I have lived near Petersfield since 1981 and often drive there. I have never noticed any unusual lack of markings. Surprising that saving money by not repainting white lines slows speeds far more than spending money on speed cameras! Is there a lesson there?
Idris Francis Fight Back With Facts Petersfield

Agree (4) | Disagree (7)
-3

Not sure if speeds will also me monitored at the end of the 3 year after period (I may have missed it in the report) but it would be useful to see if the speed reduction is maintained. As others have mentioned it probably has a greater effect at specific locations. Removing the centreline everywhere might dilute any benefits.
Nadeem, Greater Manchester

Agree (7) | Disagree (3)
+4

I ride the roads around my area very frequently and this year a great number of roads are being re surfaced with chippings laid on an amalgam of bitumen and other materials. On those roads, as you can imagine, there are no white lines for some distance and there are the slow loose chippings boards with a recommended speed limit. Nobody takes a bit of notice of that speed limit on 50 and 60mph roads, they don't slow down at all. I can't understand why or how it works in some areas and question (scientifically or otherwise) how they can obtain such a measured reduction in speeds. In the case of 30mph or 40mph roads it's quite a reduction in speed. If that is true then all roads should have their lines removed and that would save money and also we won't need the 20mph signs and that would save considerably more money. Most of the side streets do not have central lines but with cars parked both sides drivers still drive far too fast, up to and exceeding the speed limit on these minor residential roads. Won't work there.
bob craven Lancs

Agree (4) | Disagree (5)
-1

I wonder what happened in Petersfield, Hants. In the 1990s the town centre was redesigned as part of the DfT Bypass Demonstration Project. The idea was to build in uncertainty including removing white lines and even stop signs at junction. I wonder if the scheme survived in which case there will be a wealth of experience to contribute to this debate.
Kris Beuret

Agree (2) | Disagree (2)
0

As I see it the problem arises as to blame in the event of an incident where two vehicles being driven in opposite directions meet and a collision occurs. It's not as easy for a driver to admit that they were on the wrong side of the road if there is no wrong side of the road.

I know there is presently an argument against having too many street signs and to reduce signage clutter but what if we did away with stop lines at junctions? What does one suppose will happen there, based on this apparent study.

The LA have a lawful duty under the Highways Act to protect its subject on the highways. What I wonder would have happened if the opposite had occurred and accident rates had gone up, and perhaps involved the loss of life. Would the LA have been considered vicariously liable for that?
bob craven Lancs

Agree (4) | Disagree (4)
0

The first time we have a report that includes (a degree of "scientific trial") and it is discounted on the basis of expectation, anecdote and nouse. Regarding safety at failed traffic signals – beware of comparing a few hours a year against the rest of the year.
People given a choice making the wrong choice – vs – drivers on automatic making the wrong assumptions. We usually complain about the latter. Putting in centrelines that were omitted could be due to DfT influence or instruction as they were interpreting the implied guidance in the TSRGD as what had to be done.
Mark, Caerphilly

Agree (6) | Disagree (3)
+3

If there is an element of uncertainty as to a choice then it is more likely that people will make the 'wrong' choice.
Duncan MacKillop, Stratford on Avon

Agree (5) | Disagree (21)
-16

Sorry to disagree. Some years ago my LA relaid some roads and as I believe forgot to come back and put the white lines down. So I contacted them and they said that it was new policy.

They now put lines down when they have resurfaced a road. It didn't work. It didn't slow traffic down but there were no accidents or particular hazards on that road anyway. So difficult to quantify but at least it would save money wouldn't it.

Traffic lights not working is a completely different situation which is very hazardous and therefore traffic will slow as they would if all traffic lights were made into roundels ie open spaces without directions. They become a sort of roundabout without the central island as have been used elsewhere recently.
bob craven Lancs

Agree (3) | Disagree (9)
-6

I noticed the very same effect in years of traffic policing in London: when traffic lights were out at a junction, tailbacks even during periods of heavy usage were usually shorter, and drivers took a great deal more care than normal. I have no recollection of ever attending a collision at a junction where the lights were out. That is very different from saying 'Wouldn't be a good idea to remove all the lights then?' This study seems to see a speed reduction as something that could be achieved anywhere where centre markings were removed. If such an effect is observable, and I have no doubt that it is, then once you start making line removal more common drivers will see it as less unusual and fail to slow as they are now accustomed to the concept. Once the genie is out of the bottle and the average driver is accustomed to centre lines, removing the things in a wholesale manner will achieve much less than in one location.
David, Suffolk

Agree (26) | Disagree (5)
+21