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Review the Speed Limits

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Speed guns were long overdue, but there is a problem: The limits they enforce were set decades ago, and a great deal has changed since then. With industrialisation has come daily commuting by the masses to the urban centres and vast improvements in the road networks.

Non-stop, multi-lane highways are now a reality. Car ownership is widespread. Vehicles no longer struggle to reach 80 km/h; they pass it with ease. They are laden with safety features such as seat belts, airbags and crumple zones, and previously far-fetched systems such as lane-keep assist and auto braking are now appearing on the latest models. The speed limits set in the days of single lane roads for the few lucky ones can no longer be considered realistic.

Our laws follow the general principle of 50 km/h in built-up areas and 80 km/h outside of built-up areas except for goods vehicles and transport vehicles which are limited to 65 km/h. This is laid out in the Motor Vehicles and Road Traffic Act. Sorry, owners of "T" plate vehicles - you better check your MG.W. to find out if you are restricted to 65. Remember that these limits were set decades ago when pick-ups reaching 80 km/h was a ludicrous thought bound to end in death, and before today's vehicle taxes - see my last blog entry - made them an attractive alternative to family sized sedans and SUVs. The limits as per the current laws are depicted below:


Source: Laws of Trinidad and Tobago: Motor Vehicles and Road Traffic (pdf)

This very phrasing of the speed limit laws based on being inside or outside a built-up area should be cause for concern. These limits were evidently decided upon before the time of the highway network. Few made an issue of this when the limits were rarely enforced, but that time has passed. Today as it stands, the Uriah Butler/Solomon Hochoy Highway is limited to 80 km/h and the Diego Martin Highway is limited to 50 km/h. It is time to review the limits.


Setting Speed Limits


Speed limits are set based on a number of factors including:

  • Road design and purpose
  • Presence of pedestrians
  • Expected travel time
  • Acceptability by road users

There is a lengthy handbook made available by the US Department of Transportation on this subject, available at this link if you care to read it.

Let us consider the major highways: The Beetham and Churchill Roosevelt Highways running east/west and the Uriah Butler and Solomon Hochoy Highways running north/south. These are major national highways built to high-speed standards and for significant distances are not only wide but non-stop, with traffic signals having been replaced by overpasses. Many use these highways on a daily basis to get from their homes in the east, central and south to their workplaces in Port of Spain and back again.

The design of these highways is such that in the absence of enforcement, most drivers settled in at a pace in excess of 100 km/h, especially on the non-stop portions that lie west and south of the Churchill Roosevelt/Uriah Butler Interchange. The importance of this cannot be understated. It governs the pace at which the motoring population is accustomed to navigating and the expected transit time between the major cities and towns outside of peak traffic. It is easy to cry safety at this point, but keep in mind that these roads have wide lanes with shoulders and no stopping. These highways are not engineered for slow traffic.

Higher driving speeds are not only for convenience: They are also a safety consideration. Driving a vehicle requires constant attentiveness, and monotony can set in over long distances of doing nothing but maintaining a steady speed. On a long drive at low speed, the driver is more tempted to do the things they should not be doing as a driver: take in the passing views; fiddle with the radio; risk a text message; turn to face a passenger as they speak. Perhaps worse, lethargy and drowsiness can become an issue. Did you know that drowsy driving is a major cause of vehicular accidents and can be just as dangerous as drunken driving?

All of this under consideration, major highways around the world carry speed limits in excess of 100 km/h. The below image depicts the speed limits used for major highways around the world. Keep in mind that the number in the red circle depicts km/h while the number in the black rectangle depicts the equivalent speed in mph.


Image Credit: Amateria1121 on Wikipedia (Creative Commons license)

It is not just the major national arteries either: There are numerous minor highways and main roads that need to be raised above the 50 km/h limit currently set on them. In the west for example, the Diego Martin Highway is limited to only 50 km/h, as is the Cocorite Stretch of the Western Main Road despite its design of three lanes in each direction.

Don't think for a minute that the police are giving people a "bligh" where the limits are unreasonable: Some scouring on Facebook will show that at least one person claims to have been charged for driving at 67 km/h on the Diego Martin Highway. Even the slowest of drivers have trouble adhering to that limit and 50 km/h turns Diego Martin from a quickly navigated valley to a painfully long one. In effect, 50 km/h negates the very purpose of conferring highway status to that road.

This is not to say that all limits should be increased. Roads inside of urban areas, unless designated as main roads, should be reduced to 40 km/h. Some should even be no more than 30 km/h where there is heavy pedestrian traffic. This is quite important: As this link explains, a pedestrian struck at 50 km/h (equivalent of 30 mph) has a close to 50% chance of death, while one struck at 30 km/h (equivalent of 20 mph) has almost none.

Suggested Speed Limit Changes


The idea here is that limits should be set according to the safe navigable speed of the road and the expected travel time between destinations; not rigidly at 50 or 80. Here are a few of my suggestions:

Suggested Limit (km/h) Description
30-40 Urban Roads
50-70 Main Roads
80-90 Minor Highways
90-100 Major Highways with traffic signals
100-120 Major Highways without traffic signals

Note that the suggestions show speed ranges. In other words, different parts of a given road can have different speed limits. As an example, the major highways can be 110 km/h, but increased to 120 on straight, three-laned sections and reduced to 100 where traffic signals still exist. A minor highway like the Diego Martin Highway can be 80 km/h while slightly straighter minor highways like the Audrey Jeffers Highway can be 90. Main roads can start at 50 km/h but increase to 60 or 70 where conditions permit such the previously mentioned Western Main Road at Cocorite, as well as several portions of the Eastern Main Road and Southern Main Road. Most of this should be a common sense balance between efficiency and safety.

This also is a good time to indicate that these suggested limits should apply to most vehicles including those "T" class vehicles commonly purchased as family vehicles or for hauling light loads. Very heavy vehicles such as full size buses and trailer trucks however, should probably not be permitted at 100+ km/h simply due to their reduced stopping time and survivability in the other vehicle should there be a collision. Vehicles incapable of safely maintaining highway speeds such as tractors should be outright banned from using those roads unless carried on the tray of a transport truck.

The rationale for this is to ensure that vehicles traveling on highways all maintain a similar pace. It is no secret that while speed increases the severity of a crash, it is seldom in itself the root cause. We must do our best to eliminate driver aggression, tailgating and unnecessary lane changes. These behaviours can easily lead to hitting the car in front, clipping another car in a blind spot or giving a "bad drive" by dangerously overtaking on the wrong side, all of which can have fatal consequences at highway speeds - whether the limit is 80, 100 or 120.

This therefore calls for the consideration of a minimum speed limit.


The Case for a Minimum Speed Limit


For those who think that 120 km/h sounds too fast, remember that this is only for particular road segments and is simply the maximum allowable limit - not the mandatory speed. There is however a case to be made for minimum allowable speeds on the major highways. As it stands, there is nothing stopping anyone from driving less than half the pace of the rest of the traffic, leading to the very behaviours outlined above. This is a hazard, and the simple solution here is to mandate that everyone maintains a minimum pace of within 20-30 km/h of the posted limit.

More to the point, we should recall the age-old rule: Keep left except when overtaking. There is a terrible and all too common practice where drivers get onto a multi-laned roadway, filter all the way to the rightmost lane and then maintain a pace below the posted limit. This obstructs the designated passing lane. It encourages tailgating, improper overtaking and road rage. It should not be tolerated any more than speeding or tailgating should be - that is to say, not at all.



Six speed guns throughout the entire country is far from any kind of solution. A glance at the commonplace road traffic app and website Waze can tell anyone where in the country the speed traps have been set up at any given time. What are actually needed are a mixture of fixed detectors and hand-held units.

The fixed detectors would have to be connected to a camera system and located at known accident hotspots. This of course requires that we have a modern database with which to match vehicles with their owners and some sort of mechanism to deal with cases where the driver at the time of violation may not be the registered owner - very important in households and businesses alike. Handheld systems can be universally present in all highway patrol vehicles.

It is important of course that automated systems generate two independent readings from independent sensors that both agree on a violation having taken place. All systems, automated or hand-held, must also factor in some sort of margin of error. Detecting equipment may not be perfectly calibrated, vehicle speedometers may often not be 100% accurate, and it is unreasonable and unsafe to expect a driver to keep his or her eyes glued to the speedometer instead of the road ahead - even cruise control systems fluctuate slightly as the roads dip and climb.

For this reason, most territories allow a few km/h or percentage points above the limit before a ticket is issued, and this should be no different for us. To do otherwise opens the door for fines to be easily contested in court and is a quick road to breeding public distrust in the initiative. It is important that the public view the initiative as one of road safety (trustworthy) rather than revenue generation for the state (untrustworthy).

The same cameras previously mentioned can also be used to crack down on tailgating. Lines can be painted across the roadway forming a bounding box and tailgating can be determined by the presence of two cars within the box at the same time above a particular speed. With the inclusion of text recognition technology, they can also read passing registration plates on the lookout for vehicles that have been stolen or reported as involved in criminal activity.

In other words, let's deal with the issue of speed limits and enforcement in a fair and holistic manner.

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Speed does not kill,reckless driving does, driving under the influence does,obtaining your license by corrupt means kills.in addition to the ideas proffered, no one should be allowed on the nation's  roads without completing the defensive driving course.

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Thanks for the comment Bryyo6 and very true - although excess speed above the flow of the rest of the traffic or above the road/vehicle design capabilities can be the cause of a crash!

We have a lot to do in enforcing general wreckless driving, and while it's easy to say not to allow anyone on the road without completing defensive driving, perhaps we should say that defensive driving should be part of driver's ed. We need a major overhaul of our licensing system. Theoretical instruction and close course driving should really begin at 16, and once turned 17 there should be both a learner's and a provisional permit granted before the full unrestricted permit is issued.


By the way, according to today's news, the government is looking at 100 km/h on the major highways and an as-yet unspecified upward revision on the Diego Martin Highway. We may hear of the change by next week, which would be great. The lower speed for heavy vehicles needs to be upgraded as well, and the MGW used to determine the qualification for lower speeds also needs changing.

I maintain that 110-120 can be safe on specific portions of the major highways, but I think that 100 is perfectly reasonable and should placate the fears of those who feel 110 and 120 to be too fast. I think 80 is a good, already commonly driven speed to set for the Diego Martin Highway.

I hope the changes happen soon.

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It seems as though the Ministry of Works and Transport has fallen asleep on plans to increase the speed limits.

Assurances were given that in January 2017 changes to the speed limits will be implemented.

This Government continues to talk but no action.

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