Courtesy - The Islandby Ananda Ranasinghe President-Elect
Institution of Engineers, Sri Lanka
The construction of the Southern Highway has made a significant change to our road network system. We never dreamt of having a dual carriage highway in Sri Lanka at least for the next decade. However, with the change in the government along with the resulting end to the ongoing conflict, a vast development programme has taken place with the prominent Southern Highway project taking pride of place.
However, I am quite sure that our drivers are not used to driving on a highway as we still have people who continue to drive on the right side of the road instead of the left. Quite often cyclists have taken it for granted that they could ride any way they like even on a highway. Sometimes I have noticed people doing these mistakes even in the presence of traffic police who do not take serious note of such violations.
Although covering trucks or lorries when carrying loads is mandatory in public highways, this has been done merely as a camouflage by such vehicle owners, whereas these do not safeguard the rights of pedestrians and other road users.
A few decades ago the police were very serious about stray cattle on the roads and quite correctly this is a serious threat for the safety of road users. I have come across situations where even within town limits, stray cattle are a common sight on the streets. Such type of obstacle can be a potential death trap on a high speed highway. I am not certain as to what measures have been taken on the Southern Highway to prevent stray cattle from entering the roadway.
I have also been made aware that the speed limit on the Southern Highway has been set at 120 KMPH. This is rather a high speed limit where the braking distance might be a few metres. Therefore, by the time one reacts to an emergency one may have travelled a long distance and the repercussions of this travelling distance could be quite disastrous. Most traffic engineers believe that speed limits should be posted to reflect the maximum speed considered to be safe and reasonable by the majority of drivers using the roadway under favourable conditions.
Procedures used to set speed limits have evolved through years of experience and research. Most countries set safe and reasonable maximum speed limits based on the results of an engineering and traffic investigation. At the same time, the engineers use the 85th percentile speed as a major factor in selecting the appropriate speed limit for a given street or highway. Other factors such as roadside development, accident experience and design speed are often subjectively considered. The 85th percentile is a major parameter used by traffic engineers and transport planners and is defined as: "The speed at or below which 85% of all vehicles are observed to travel under free flowing conditions past a nominated point".
Free Flowing is defined as: "A vehicle is considered to be under free flowing conditions when the preceding vehicle has at least 4 seconds headway." Therefore, a detailed study has to be done before fixing speed limits and it shouldn’t be an arbitrary decision of an individual.
Our drivers still have the habit of stopping or slowing down at the centre of the lane without any warning, using signals improperly when overtaking, sight-seeing when travelling, using cell-phones while driving, not wearing seat belts, overloading etc. Some vehicles even with damaged lights still continue to be driven on public roads. Their tyres are not tested and they may not be good enough for driving at high speeds. All these add up to serious accidents on public highways. Sri Lanka has a death rate of six persons per day on highways. Therefore, it could have been much better had we started the speed limit at about 85 KMPH and observed the accident rate, before increasing the speed limit up to 120 KMPH, which is extremely high, even on a highway, especially for Sri Lanka.
The commencement point of the Southern Highway, according to information available, is somewhere around the Kottawa area. Therefore, link roads leading to Kottawa have to be built in order to gain the maximum benefit of this highway. Presently, the Old Kottawa Road is being widened in order to take more traffic. This should have been done at the commencement of the construction of the Southern Highway.
Widening involves not only road construction, but there is a lot of additional work to be done. For example, service lines have to be laid or shifted to the side of the road. In some countries, they provide a separate area parallel to the new road in order to lay the service lines to minimise damage to the new highway. It is also important that at suitable intervals, ducts or pipes be laid in order to connect the services from one side of the road to the other. Therefore, proper planning has to be done before commencement of any roadwork. Expediting work during the day and night is a good thing, but it does not mean that one should do planning hurriedly or ignore proper planning. In most of the major roads or road widening projects that have already been constructed, there is the problem of maintaining services or introduction of new services as no solutions had been made for this purpose at the planning stage. Shifting a water line or a telecommunication cable is extremely expensive and time consuming. The author has experienced by his work abroad that cables have sometime to be ordered or fabricated as telecommunication cables are not readily available in the market and therefore roadwork might have to be interrupted for a few months, until the cables are relocated. This emphasises the importance of planning a project and at the same time it is also important that once the design work is done it has to be studied by experienced engineers, since quite often, designs are done by junior engineers.
A good example of this is the roundabout at Parliament Road near the Waters Edge Hotel intersection. Although the earlier road was not as wide as the present one it had a user-friendly roundabout by which to negotiate and travel safely. After reconstruction however, the roundabout has now been replaced by a sharp bend which acts as a bottleneck, thereby causing a situation where vehicles coming from both directions have to face each other, thus creating a dangerous intersection. As a result of this, it has now become always necessary for a police constable to direct vehicles at this intersection. This shows that road improvements can also be counter-productive, if no proper planning has been done.
The author has also observed road widening being carried out on High Level Road which is an access road to the Southern Highway. This may involve relocation of a substantial amount of services, such as electricity, water, telephone lines etc. These relocations cannot be done overnight and it might sometimes take a few years. Therefore, it would have been much better had such relocations started at least a few years back. Sometimes, for planners, it is just a matter of calling for a relocation of a water line, but for a water supply engineer, this could mean a major job where planning has to be done with pipes and other fittings that need to be imported, maintenance of existing services while the line is being relocated, land acquisition, preventing disruption to other existing services, etc. Therefore, when widening a road the highway engineer has to allow for all these eventualities. Once a retaining wall is constructed at exorbitant cost, it cannot be relocated for further widening. Therefore, any structure that a highway engineer builds on the road has to be well thought out. While highway engineers were constructing the intersection in front of Waters Edge, as a driver who used this road quite often, I am sure I have not been alone in observing that there was something wrong with the planning of this intersection.
I have also observed that a massive retaining wall is being built in front of Dharmapala College on High Level Road. Once such structures are built, widening of the road is restricted, as one could widen only up to the retaining wall. Therefore, when taking such decisions one has to look into the necessary width of the road and the requirements for future expansion etc. Also, when spending money on such work, utmost care should be taken before construction commences.
There are many multi-billion rupee projects which have been constructed which people still believe have been done at the wrong locations.
Since Sri Lankan drivers are not used to driving in lanes or are not bothered to drive within a lane, this attitude could be quite dangerous for people driving on a highway at very high speeds. Overtaking is also done in a very haphazard manner and on many occasions, these traffic violations continue without being penalized by authority. Flashing lights and taking right turns are very common practices used by some of the drivers. There is no such signal in the highway code. However, some drivers think that they could violate any rule by merely flashing their lights at an oncoming vehicle. Therefore, drivers have to be disciplined before they are expected to observe very high speed limits. I have seen recently in many locations on public highways, where there are damages at the centre of the road into which a passer-by with good intention may plant a branch of a tree in order to warn road users of impending danger. However, if there is a potential danger due to the failure of the roads, such area should be immediately cordoned off by the authorities and illuminated especially at night. Sadly, this does not happen often enough either due to ignorance or they have less value for human life.
The above practices indicate that we are still far away from applying speed limits of well over 100 KMPH in our highways. The authorities who fix these speed limits may have not gone deep enough into the statistics to evaluate how dangerous these speeds can be to travellers. Therefore, I believe that a fair amount of study has still to be done before extending our speed limit to more than 85 KMPH.
