In periods of high growth, it is very easy for engineers, designers and planners of infrastructure to concentrate on meeting impending targets rather than taking a holistic approach to deliver what is appropriate, efficient and safe for the long-term social and economic demands. The importance of road infrastructure for communities to function and generate effective economic growth cannot be overemphasised. Roads must however, be designed and constructed to certain mandatory safety and functional standards for realistic life-cycle benefits to be accrued. Roads and highway designers therefore, have professional and moral obligation to the safety of the different categories of road users: drivers, passengers, pedestrians, the disabled and should include cart pullers and roadside hawkers. Safety cannot be compromised for any reasons.
Incidentally, accident statistics of Ghana?s roads (number of casualties per ten thousand people) is not desirable ? ranked among the worst in the world. Although many factors contribute to road traffic accidents, there is little doubt that engineering and planning improvements can affect road-user behaviour in such a way that accidents are less likely to occur or, when they do occur, the environment can be more ?forgiving?. In other words, safer roads and well-planned roadside furniture/environment (or implementation of road safety standards) reduce the likelihood and severity of accidents.
According to a WHO newsletter on road safety published in November 2003, road traffic injuries are a deadly scourge, taking the lives of 1.2 million men, women and children around the world each year. Hundreds of thousands more are injured on our roads, some of whom become permanently disabled. Road traffic injuries involve issues of equity. They disproportionately affect the poor in developing countries, where the majority of road crash victims are vulnerable road users ? pedestrians, cyclists, children, and passengers. Whilst road traffic accident rates are generally improving in high-income economies, many developing countries in Africa and Asia face a worsening situation (DETR, 1999). Injuries and disability resulting from road traffic crashes put a significant strain on economies, typically consuming between 1 and 3 per cent of a country?s gross national product per annum (UN, 2003).
During my visit, I travelled from Accra to Dormaa Ahenkro in the Brong Ahafo Region via Kumasi and Sunyani, and continued to Yaakrom, a small town on the Ghana-Ivory Coast boarder. I made several trips within Accra, Kumasi and Sunyani visiting friends and family. As someone who works in the consulting engineering industry, delivering infrastructure projects, I acquainted myself with the technical aspects of both Ghana?s urban and rural roads with some fascination. I marvelled at how quickly the motherland had advanced and appreciated the introduction of positive cutting-edge technology in the form of:
This article aims to focus on some observed design features on Ghana?s roads, which can be improved to reduce the likelihood and severity of accidents, enhance user-friendliness and improve traffic flows. Where possible, recommendations will be made based on European standards tailored to suit our emerging economy. It is intended to inform policy makers, including the general public and help develop improvements to our roads and highways with comparatively minimum additional expenditure.
The areas of interest are interrelated and not possible to simplify under individual headings. For the purpose of this article, the pertinent areas will be reviewed under the following headings and cross-referenced where possible:
The resources required to install road markings is infinitesimal compared to the capital cost of road construction. Road markings are cheap ways of imparting information to drivers and other road users, yet long stretches of some sealed primary roads in Ghana have no road markings ? the easiest, quickest and final activity in the road construction process.
A variety of measures can be used to influence driver behaviour and perception. The essence of traffic calming, however, lies not in the use of specific measures but in the overall objective to create safer roads and better environmental conditions. In Ghana, the commonest form is the road hump sometimes called the ?sleeping policeman?. Narrow road humps installed across roads in pairs of twos, threes or more such as those found in some areas in Ghana may be referred to as ?rumble strips?.
In developed countries, traffic calming is seldom used on roads with speed limits greater than 50 km/hour. Its use in Ghana on primary roads where speeds are relatively higher due to lack of resources and mechanisms to enforce speed regulations, especially on approaches to towns and villages, pedestrian crossings, schools, etc is considered appropriate provided the strategic objectives of improving driver behaviour, concentration, awareness and reducing speeds are achieved.
For traffic calming to be effective on high speed roads, it must always be preceded by a speed reduction measure which may be in the form of warning signs indicating the road feature ahead. Sudden encounter of road humps is dangerous! It is no good installing road humps without the necessary advanced warning as seen in some areas in Ghana. It has been found, for example, that the most effective traffic calming measures are generally those that are very conspicuous.
I came across a ?Do-It-Yourself? road hump in a village in the Brong Ahafo Region where a tree trunk had been partially embedded across the roadway and covered with loose gravel and no prior warning.
Let us educate the public that road humps used in isolation and out-of-nowhere is a recipe for disaster.
Pedestrian facilities in Ghana include footways, footbridges and pedestrian crossings. It was observed that pedestrian facilities in Ghana were designed for the ?normal? pedestrian resulting in the young, the elderly, the disabled, the kaya-kaya and the cart puller being disadvantaged when walking.
Considering the two foot bridges at Kaneshie, the following questions may be asked:
The commonest at-grade pedestrian crossings in Ghana are the zebra crossings where the pedestrian has legal priority over the motor vehicle. A motor vehicle must therefore give way to a pedestrian who steps onto a zebra crossing and this precedence continues while the pedestrian is on the carriageway.
To ensure safety of pedestrians, drivers need to be warned in advance on approach to zebra crossings. Solid and conspicuous road markings are required on the carriageway approximately twenty metres either side of the crossing strip. Crossing distance is made as short as practicable and where site conditions permit, raised refuge islands are required to protect users and give pedestrians with infirmities some kind of rest. To assist the partially sited or blind users and the disabled, high-visibility textured paving or tactile pavement is incorporated at the footway side and kerbs dropped for wheel chair access. Guardrails may be required to offer extra protection to waiting pedestrians and also to direct walkers onto the crossing. Flashing lights or beacons are incorporated to make zebra crossings more conspicuous in some countries. In Britain, zigzag, double yellow or double red lines substitute for edge and lane markings either side of pedestrian crossings. The relevant design standards encourage designers to incorporate high-friction surfacing approximately fifty metres in advance of pedestrian crossings to assist and minimise the risk of skidding during breaking, thus offering additional protection to users.
Broken lane delineators with no edge of carriageway markings characterised some zebra crossings seen in Accra, which theoretically allow overtaking, parking and waiting either side of the crossings. Zebra crossings strips are marked on carriageways out-of-nowhere with not even dropped kerbs to encourage usage by the disabled in wheel chairs. There is a pedestrian crossing on the three-lane, dual carriageway Kasewa-bound Kaneshie road with no physical controls, no advanced warning, no raised refuge island, inadequate road markings, etc. At minimum, there should be a sign marked for users as ?pedestrians use this facility at their own risk?. How an uncontrolled pedestrian priority crossing works safely on a busy multi-lane carriageway in a country where driver behaviour at crossings is very poor defies comprehension, fundamental traffic rules and severely compromises the safety of both the pedestrian and the driver.
Junction at crossroads ahead between a non-primary route and a primary route which is a ring road and which also leads to a railway station and free parking in one direction and to a tourist attraction in the other. | |
The number of a non-primary route leading to a primary route with destinations and distances | |
Typical Directional Signs in UK: Source: The Traffic Signs Regulations and General Directions 2001-Draft (UK) |
Road signing is an area in highways, traffic and transportation engineering that is benefiting from advances in modern technology. New road signs being promoted in developed countries include variable message signs, in-vehicle information and navigation systems, highway telematics, etc., and are based on satellite communication, video surveillance and global positioning systems. These are geared towards achieving a comprehensive intelligent transport system.
Road signing in Ghana is generally very basic and a complete overhaul of the system is essential as some of the discussions above already show. The only signs identifiable in Ghana within the highway corridor are probably the private advertising billboards, which may be illegal. Numbers of signs per stretch of road, typeface, size, colour, mounting height and design have not been regulated. Some of these bear poor artworks with inscriptions like ?Enso Nyame Ye Chop Bar?, ?Christ the King Autos?, ?No. 1 Shoe Shine?, etc., which are utterly irrelevant to the driving experience. Approaches to some major intersections in Kumasi and Accra are cluttered with so many overlapping signs that junction visibility is non-existent ? dangerous to the motorist and other road users. These signs undermine the serenity of road space, are stressful in particular to the non-local drivers, and impact on the environment in the form of visual intrusion and obstruction.
As a matter of urgency, policy and decision makers have to consider mounting well-designed directional signs to major landmarks such as universities, schools and colleges, cultural centres, hospitals, hotels, cities and towns, etc., on selected roads if Ghana has ambitions to develop the tourist industry. Is it not preferable and less interfering for tourists and non-locales to get to their destinations without relying on guides? The footbridges which could equally serve as sign gantries have rather been disadvantaged to chaotic and intrusive jumble of advertising billboards.
Most highway design standards would recommend some protection for concrete obstructions close to the running edge, usually in the form of safety fencing to contain errand vehicles and avoid impact. These concrete structures are particularly dangerous on unlit urban and rural roads. The effect increases on bends, peaks and troughs, and on unsealed roads where vehicles utilise wider road space to avoid deteriorated sections.
In the absence of safety fencing, the most cost-effective way to downgrade the risk of impact is to coat the structures with high visibility reflective paint in vertical or horizontal stripes of contrasting colours (usually red, yellow or black stripes in white background). Concrete or stone lined ditches either side of settlements along high-speed rural and urban roads have similar safety implications. This group of ditches could be lined with inexpensive marker posts or bollards with reflective bands to make them more conspicuous.
In Accra, I saw manholes connecting 600 mm diameter sewers, over two metres deep with no covers on a busy footway and nothing to alert pedestrians of the danger. Is this blatant disregard of public safety and attempts to test the vigilance of the innocent schoolchild or someone going about his/her daily business?
There have been efforts to introduce cutting-edge technology to facilitate pedestrian flow especially within urban areas. However, the designs are disproportionately unfavourable to people with natural infirmities, including the elderly, kaya-kaya, cart pullers and roadside hawkers.
Roads and highways in Ghana are inadequately sign posted, and road markings are sometimes non-existent over long stretches of highway. Where departures from acceptable standards have been adopted, provision of well-designed road signs and markings can significantly contribute to safe and efficient operation of road networks. Inadequate road markings increase the chaos and accident potential on roads, particularly in areas where complex and conflicting manoeuvres are permissible. Placement of advertising billboards appears unconstrained and consequently clutters the highway corridor and impacts on visibility to the detriment of road users.
Many of the safety implications on Ghana?s roads are obvious, can be highlighted by independent safety auditing and assessment, and eliminated through application of low-cost corrective measures. Given the substantial maintenance backlog of existing roads, it not considered acceptable to simply build new networks without rectifying deteriorated sections of existing roads and introducing countermeasures to get rid of safety hazards.
In periods of high growth, it is very easy for engineers, designers and planners of infrastructure to concentrate on meeting impending targets rather than taking a holistic approach to deliver what is appropriate, efficient and safe for the long-term social and economic demands. The importance of road infrastructure for communities to function and generate effective economic growth cannot be overemphasised. Roads must however, be designed and constructed to certain mandatory safety and functional standards for realistic life-cycle benefits to be accrued. Roads and highway designers therefore, have professional and moral obligation to the safety of the different categories of road users: drivers, passengers, pedestrians, the disabled and should include cart pullers and roadside hawkers. Safety cannot be compromised for any reasons.
Incidentally, accident statistics of Ghana?s roads (number of casualties per ten thousand people) is not desirable ? ranked among the worst in the world. Although many factors contribute to road traffic accidents, there is little doubt that engineering and planning improvements can affect road-user behaviour in such a way that accidents are less likely to occur or, when they do occur, the environment can be more ?forgiving?. In other words, safer roads and well-planned roadside furniture/environment (or implementation of road safety standards) reduce the likelihood and severity of accidents.
According to a WHO newsletter on road safety published in November 2003, road traffic injuries are a deadly scourge, taking the lives of 1.2 million men, women and children around the world each year. Hundreds of thousands more are injured on our roads, some of whom become permanently disabled. Road traffic injuries involve issues of equity. They disproportionately affect the poor in developing countries, where the majority of road crash victims are vulnerable road users ? pedestrians, cyclists, children, and passengers. Whilst road traffic accident rates are generally improving in high-income economies, many developing countries in Africa and Asia face a worsening situation (DETR, 1999). Injuries and disability resulting from road traffic crashes put a significant strain on economies, typically consuming between 1 and 3 per cent of a country?s gross national product per annum (UN, 2003).
During my visit, I travelled from Accra to Dormaa Ahenkro in the Brong Ahafo Region via Kumasi and Sunyani, and continued to Yaakrom, a small town on the Ghana-Ivory Coast boarder. I made several trips within Accra, Kumasi and Sunyani visiting friends and family. As someone who works in the consulting engineering industry, delivering infrastructure projects, I acquainted myself with the technical aspects of both Ghana?s urban and rural roads with some fascination. I marvelled at how quickly the motherland had advanced and appreciated the introduction of positive cutting-edge technology in the form of:
This article aims to focus on some observed design features on Ghana?s roads, which can be improved to reduce the likelihood and severity of accidents, enhance user-friendliness and improve traffic flows. Where possible, recommendations will be made based on European standards tailored to suit our emerging economy. It is intended to inform policy makers, including the general public and help develop improvements to our roads and highways with comparatively minimum additional expenditure.
The areas of interest are interrelated and not possible to simplify under individual headings. For the purpose of this article, the pertinent areas will be reviewed under the following headings and cross-referenced where possible:
The resources required to install road markings is infinitesimal compared to the capital cost of road construction. Road markings are cheap ways of imparting information to drivers and other road users, yet long stretches of some sealed primary roads in Ghana have no road markings ? the easiest, quickest and final activity in the road construction process.
A variety of measures can be used to influence driver behaviour and perception. The essence of traffic calming, however, lies not in the use of specific measures but in the overall objective to create safer roads and better environmental conditions. In Ghana, the commonest form is the road hump sometimes called the ?sleeping policeman?. Narrow road humps installed across roads in pairs of twos, threes or more such as those found in some areas in Ghana may be referred to as ?rumble strips?.
In developed countries, traffic calming is seldom used on roads with speed limits greater than 50 km/hour. Its use in Ghana on primary roads where speeds are relatively higher due to lack of resources and mechanisms to enforce speed regulations, especially on approaches to towns and villages, pedestrian crossings, schools, etc is considered appropriate provided the strategic objectives of improving driver behaviour, concentration, awareness and reducing speeds are achieved.
For traffic calming to be effective on high speed roads, it must always be preceded by a speed reduction measure which may be in the form of warning signs indicating the road feature ahead. Sudden encounter of road humps is dangerous! It is no good installing road humps without the necessary advanced warning as seen in some areas in Ghana. It has been found, for example, that the most effective traffic calming measures are generally those that are very conspicuous.
I came across a ?Do-It-Yourself? road hump in a village in the Brong Ahafo Region where a tree trunk had been partially embedded across the roadway and covered with loose gravel and no prior warning.
Let us educate the public that road humps used in isolation and out-of-nowhere is a recipe for disaster.
Pedestrian facilities in Ghana include footways, footbridges and pedestrian crossings. It was observed that pedestrian facilities in Ghana were designed for the ?normal? pedestrian resulting in the young, the elderly, the disabled, the kaya-kaya and the cart puller being disadvantaged when walking.
Considering the two foot bridges at Kaneshie, the following questions may be asked:
The commonest at-grade pedestrian crossings in Ghana are the zebra crossings where the pedestrian has legal priority over the motor vehicle. A motor vehicle must therefore give way to a pedestrian who steps onto a zebra crossing and this precedence continues while the pedestrian is on the carriageway.
To ensure safety of pedestrians, drivers need to be warned in advance on approach to zebra crossings. Solid and conspicuous road markings are required on the carriageway approximately twenty metres either side of the crossing strip. Crossing distance is made as short as practicable and where site conditions permit, raised refuge islands are required to protect users and give pedestrians with infirmities some kind of rest. To assist the partially sited or blind users and the disabled, high-visibility textured paving or tactile pavement is incorporated at the footway side and kerbs dropped for wheel chair access. Guardrails may be required to offer extra protection to waiting pedestrians and also to direct walkers onto the crossing. Flashing lights or beacons are incorporated to make zebra crossings more conspicuous in some countries. In Britain, zigzag, double yellow or double red lines substitute for edge and lane markings either side of pedestrian crossings. The relevant design standards encourage designers to incorporate high-friction surfacing approximately fifty metres in advance of pedestrian crossings to assist and minimise the risk of skidding during breaking, thus offering additional protection to users.
Broken lane delineators with no edge of carriageway markings characterised some zebra crossings seen in Accra, which theoretically allow overtaking, parking and waiting either side of the crossings. Zebra crossings strips are marked on carriageways out-of-nowhere with not even dropped kerbs to encourage usage by the disabled in wheel chairs. There is a pedestrian crossing on the three-lane, dual carriageway Kasewa-bound Kaneshie road with no physical controls, no advanced warning, no raised refuge island, inadequate road markings, etc. At minimum, there should be a sign marked for users as ?pedestrians use this facility at their own risk?. How an uncontrolled pedestrian priority crossing works safely on a busy multi-lane carriageway in a country where driver behaviour at crossings is very poor defies comprehension, fundamental traffic rules and severely compromises the safety of both the pedestrian and the driver.
Junction at crossroads ahead between a non-primary route and a primary route which is a ring road and which also leads to a railway station and free parking in one direction and to a tourist attraction in the other. | |
The number of a non-primary route leading to a primary route with destinations and distances | |
Typical Directional Signs in UK: Source: The Traffic Signs Regulations and General Directions 2001-Draft (UK) |
Road signing is an area in highways, traffic and transportation engineering that is benefiting from advances in modern technology. New road signs being promoted in developed countries include variable message signs, in-vehicle information and navigation systems, highway telematics, etc., and are based on satellite communication, video surveillance and global positioning systems. These are geared towards achieving a comprehensive intelligent transport system.
Road signing in Ghana is generally very basic and a complete overhaul of the system is essential as some of the discussions above already show. The only signs identifiable in Ghana within the highway corridor are probably the private advertising billboards, which may be illegal. Numbers of signs per stretch of road, typeface, size, colour, mounting height and design have not been regulated. Some of these bear poor artworks with inscriptions like ?Enso Nyame Ye Chop Bar?, ?Christ the King Autos?, ?No. 1 Shoe Shine?, etc., which are utterly irrelevant to the driving experience. Approaches to some major intersections in Kumasi and Accra are cluttered with so many overlapping signs that junction visibility is non-existent ? dangerous to the motorist and other road users. These signs undermine the serenity of road space, are stressful in particular to the non-local drivers, and impact on the environment in the form of visual intrusion and obstruction.
As a matter of urgency, policy and decision makers have to consider mounting well-designed directional signs to major landmarks such as universities, schools and colleges, cultural centres, hospitals, hotels, cities and towns, etc., on selected roads if Ghana has ambitions to develop the tourist industry. Is it not preferable and less interfering for tourists and non-locales to get to their destinations without relying on guides? The footbridges which could equally serve as sign gantries have rather been disadvantaged to chaotic and intrusive jumble of advertising billboards.
Most highway design standards would recommend some protection for concrete obstructions close to the running edge, usually in the form of safety fencing to contain errand vehicles and avoid impact. These concrete structures are particularly dangerous on unlit urban and rural roads. The effect increases on bends, peaks and troughs, and on unsealed roads where vehicles utilise wider road space to avoid deteriorated sections.
In the absence of safety fencing, the most cost-effective way to downgrade the risk of impact is to coat the structures with high visibility reflective paint in vertical or horizontal stripes of contrasting colours (usually red, yellow or black stripes in white background). Concrete or stone lined ditches either side of settlements along high-speed rural and urban roads have similar safety implications. This group of ditches could be lined with inexpensive marker posts or bollards with reflective bands to make them more conspicuous.
In Accra, I saw manholes connecting 600 mm diameter sewers, over two metres deep with no covers on a busy footway and nothing to alert pedestrians of the danger. Is this blatant disregard of public safety and attempts to test the vigilance of the innocent schoolchild or someone going about his/her daily business?
There have been efforts to introduce cutting-edge technology to facilitate pedestrian flow especially within urban areas. However, the designs are disproportionately unfavourable to people with natural infirmities, including the elderly, kaya-kaya, cart pullers and roadside hawkers.
Roads and highways in Ghana are inadequately sign posted, and road markings are sometimes non-existent over long stretches of highway. Where departures from acceptable standards have been adopted, provision of well-designed road signs and markings can significantly contribute to safe and efficient operation of road networks. Inadequate road markings increase the chaos and accident potential on roads, particularly in areas where complex and conflicting manoeuvres are permissible. Placement of advertising billboards appears unconstrained and consequently clutters the highway corridor and impacts on visibility to the detriment of road users.
Many of the safety implications on Ghana?s roads are obvious, can be highlighted by independent safety auditing and assessment, and eliminated through application of low-cost corrective measures. Given the substantial maintenance backlog of existing roads, it not considered acceptable to simply build new networks without rectifying deteriorated sections of existing roads and introducing countermeasures to get rid of safety hazards.