Speed limits change very quickly. Motorists looking away just for a moment, or a truck obscures vision just at the wrong moment, and you miss the speed limit sign altogether.

In Adelaide, where we are based, it is possible to be driving in 6 different speed limit-zones, if you include the 25 km/h, when school-zone limits apply.

Without realizing, you could be breaking the speed limit. There has to be an easier way! We may have found one.  

WHY NOT ..paint every tenth centre-line a different color to white, if the speed limit is not 60* km/h?

*Please note: Suburban Streets are now 50 km/h. This complicates this issue even more. A simpler system to the current one (the speed limit is 50 km/h, unless signs say otherwise) is urgently required!

A change of speed limit could not easily be missed. Plus there would be a constant reminder, what the speed limit is on a particular stretch of road, where the speed is not 60 km/h.   

Our idea only requires 3 colours (red, green and yellow) to be used. Six colours would be confusing.

Only every 10th line or so needs to be colour-coded.

A road with a solid white centre-line would be over-painted every thirty meters to indicate what the speed limit is on this suburban stretch of road.

Everyone knows the colours already:

Red 90

Amber 80

Green 70

Streets where the speed limit is 60 km/h or under, or above 90 km/h, would not be colour-coded under this system.

There is another aspect to this radical proposal: This system would allow for authorities to paint green lines for a short distance within a 60 km/h zone, simply to indicate that for this short stretch of road 70 km/h is allowed, e.g when there are no driveways or side roads etc.

I am not suggesting to do away with traditional speed signs. This colour-coding idea is meant to be an additional help to motorists, who are less likely caught speeding, because they were unaware of the speed restriction.