CASE STUDY
THE CAUSES OF CONGESTION ON THE TETTEH QUARSHIE AKO-ADJEI CORRIDOR
AND
ICT SERVICES REQUIRED FOR DECONGESTION
Rev. Lambert Ntibrey, Aalborg University MICT Project
Supervisors: Prof. Knud Erik Skouby (Aalborg University(CMI) , Dr. Robert A.Baffour (GTUC)
2011
Hypothesis
There is congestion on the Tetteh Quarshie – Ako-Adjei corridor and ICT is required by way of monitoring, among others, of the corridor to assist in its decongestion.
Research Methodology
The methodology used in the case study of congestion on the corridor include literature review of historical efforts on congestion and efforts of the government in decongestion, participatory observation, interviews and video imaging of traffic related issues on the corridor and personal experiences of the author as a driving road user for 20 years and resident in Adenta – Pantang junction beyond the Tetteh Quarshie interchange and commuting the inner city through the corridor.
DEFINITION
Congested operations is defined as
…the entire range of operations which may be experienced when traffic demand approaches or exceeds, or both, the capacity of the signal.(Dineen, 2000)
HISTORICAL EFFORTS
The Corridor is situated within the Accra Metropolitan Assembly (AMA) administrative jurisdiction. According to Ralph Mills-Tettey (no year), employment needs and its resultant urban migration has brought much pressure to bear on Accra and its environs. This results into unbearable problems for the built environments of Accra, where planning is already a problem (Ralph Mills-Tettey, no year; Grant, 2011). Some of these problems include housing, development control, transportation and traffic management.(Ralph Mills-Tettey, no year)
The problems have been further worsened by the displacement of inner city residents as a result of converting inner city residential areas into commercial centers. People who cannot get reasonable accommodation tend to resettle away from the inner city. (Ralph Mills-Tettey, no year). This extends to about 10km beyond Tema (Sakalogues, 2010) and thus to about 40km from the Central Business District.
There are a growing numbers of people living outside the area of jurisdiction of the Accra Metropolitan Assembly (AMA) and commute to work within this area. They commute from places like Kasoa, North Gbawe, Madina, Adenta, Amasaman, Ashongman, Nsawam and Aburi, Ashiaman, Sakumono, Spintex Road Area and Tema township. (Ralph Mills-Tettey, no year)
Congestion on the Tetteh Quarshie Ako-Adjei Corridor
Attempts to use either of the various available alternate routes from Sakumono to the Central Business District, takes an average of about 2 hours. The result is higher rate of fuel consumption and increased pollution(Sakalogues, 2010).
30 minutes was spent on the motorway between Action Chapel and the Toll booth, a distance of less than 2kilometres. A bad situation is exacerbated by many drivers who drive on the shoulders of the roads to avoid a queue (Sakalogues, 2010).
The heavy traffic on the Tetteh Quarshie and Motorway sections, disappeared on the removal of the toll booth and resurfaced when the electronic gates were introduced (Sakalogues, 2010).
Installation of traffic lights at wrong places and non-attendance to road defects have contributed to congestion on the Spinet road leading to Tetteh Quarshie Interchange.(Gyan-Appenteng, 2011)
Ralph Mills-Tettey( no year) found out that the slow and tedious movement of traffic on major roads in Accra at present during the rush hours are due to too many small passenger-capacity private cars, taxis and mini buses (trotros) plying the roads of Accra. No restrictive policy on the growing number of licensed small passenger-capacity taxis and the roads they could use.(Ralph Mills-Tettey, no year)
Accidents on the corridor
According to Airport District Police Commander, Chief Superintendent Anderson Fosu-Ackaah three hundred and thirty seven road accidents involving 502 vehicles were recorded between January and 26 April 2010 on the 37 Military Hospital Airport stretch of the road and on the Motorway. Fifteen lives were lost in these accidents. Even though the introduction of traffic lights have reduced the number of fatal accidents recorded around the Tetteh Quarshie interchange on the Madina-37 stretch, many accidents are still being recorded. Road users, particularly drivers need to be cautious(Modern Ghana, 2010).
Over speeding, disregard for road signs and drivers inability to display reflective triangles when their vehicles break down are some of the major factors behind the accidents. Passengers must muster the courage to ask over speeding drivers to slowdown.(Modern Ghana, 2010)
Decongestion efforts
“In the past few years there have been several road improvement works on major transit routes in the city like the Kanda Highway, from the 37 Military Hospital to Achimota Forest, Independence Avenue to the Airport, redirecting traffic on Kwame Nkrumah Avenue and Kojo Thompson Road in opposite directions.”(Ralph Mills-Tettey, no year)
According to the Metro Works Engineer of the Department of Urban Roads, Alhaji Abass Awolu The Department of Urban Roads (DUR) targeted about GH¢8million in 2009 to complete ongoing road projects within the Accra metropolis to make them more motorable and reduce pollution. This scheme included work of traffic lights and efforts to have a central control system(Ghana Business News.com, 2009)
According to Ralph Mills-Tettey ( no year), mass transit buses have been introduced. “Ghana cannot for now afford an underground metro transport system that would carry more passengers, reduce commuting times and road traffic”. The resuscitation of a basic inter-city rail transport network is receiving high attention. A trial Nsawam Accra daily rail service is ongoing. Similar systems running in other part of the city can bring a lot of relief and make commuting less stressful for many workers in the city.(Ralph Mills-Tettey, no year)
The Accra Mayor, Alfred Vanderpuje stated that “inner lanes were being designed to try and ease the situation there” (Ghanaweb, 2010). Work is also ongoing on the Spintex Road. This was earnestly being pursued for completion by December 2010 by the Deputy Minister for Roads, Dr. Oakley Quaye Kumah, (GhanaWeb, 2010) thus showing the determination of government to decongest the corridor.
According to the Daily Graphic, the ongoing construction works on the Accra Polo Club-Spintex road is aimed at reducing traffic on the Tetteh Quarshie Interchange by diverting traffic from the Central Business District [Ako Adjei Interchange extended] and the Tetteh Quarshie interchange, which is usually high during peak hours, onto the Spintex Road and other linked roads including Madina (Daily Graphic, 2010).
Traffic calming measures by Ghana Highways Authority
“The speed of vehicles travelling through populated areas is likely to be one of the most important safety issues on Ghana highways in general and this was also indicated in previously obtained accident data.” One of the main problems is vehicle / pedestrian conflicts. Reducing the speed will therefore give certain safety benefits.(Ghana Highways Authority, 2010)
In Ghana the drivers do not adhere to speed limits, and the police are not capable of enforcing this. To ensure reduced speed it is therefore necessary to use traffic calming devices. This addendum describes the traffic calming devices Ghana Highway Authority uses on their roads, where to use them and how they should be designed.(Ghana Highways Authority, 2010)
ANNEX 0‑1 outlines the measure taken by the Ghana Highways Authority in calming traffic.
Factors contributing to congestion
Various factors have been identified as causes of congestion on the corridor deduced from the various modes of the research methodology.
- Road network effects
Understanding the road network effects requires the appreciation of some aspects of the dynamics of Accra in respect of road users’ strategies in traffic management.
The diffusion of traffic on the corridor from the Central Business District uses various routes. The Google Map® of Accra in context is shown in 0‑1
A common phenomenon is that road users shy away from one road link at a time supposing that there is traffic on the other. This sometimes results in the dreaded road being free and traffic congesting on the other.
All road networks that diffuse traffic from the Central Business District and must interchange at Tetteh Quarshie seek the closest possible entry to the interchange.
This has the end effect of:
· Entry through the back of Gulf House into the interchange results in congestion at the Gulf House junction.
· at this point, two alternatives are available to traffic in the Madina direction
o either routing by going onto the Interchange to the right and descending to the left, creating congestion as a result of poor traffic metering under the interchange,
o or route through the Polo junctions to Polo roundabout and back into the interchange.
· The Polo junction situation is further worsened by the re-convergence of the diffused traffic through the HIPIC junction coming from Airport West and the Achimota – Tetteh Quarshie motorway combining with the inflow from the Aviation House intersection[Table 4,2].
· The next closest entry is the Association International intersection. The entire environ of the Association International School receives a lot of vehicular activity during the evening rush hours. The final entry point from this School to the intersection gets converted into 3 or 4 lanes, making use of all the shoulders of the road and the frontage of residencies. The effect is the blockage of vehicles coming out of the corridor.
· The Airport intersection receives much traffic. The entry from the Airport Residential Area direction has a three-lane capacity. Human intervention, either by the police in the form of traffic warden is required sometimes to maintain order at the junction about 50m before the entry to the Airport junction. This further spills over through a link road to Association International School area.
· The Akuafo intersection and the Ako-Adjei interchange are major commuting link carrying traffic from virtually the entire eastern side of the corridor crossing to the western. The at the Akuafo intersection is worsened by the activities of the commercial vehicle drivers at the 37 Military Hospital bus bays that are close to the intersection.
· The re-convergence of diverted traffic at the Flag Staff House intersection, through the Switchback road back into the corridor at the 37 Military Hospital increases the congestion at the 37 Hospital pedestrian crossing light.
ICT Service required for road network effects management:
The decision of journey route begins from a present location. Lack of traffic information leads to traffic misjudgment by drivers. The consequence on the corridor during the rush hours is congestion at the intersections and road networks in the immediate vicinity of the intersections. Single lane roads closest to these entry points into the corridor get converted temporarily into multiple lanes by impatient drivers. This prevents the smooth movement of traffic exiting from the corridor
The intervention of the Police and traffic wardens are employed to deal with such situations.
ICT services required are
· Traffic situation and route guidance via VMS. The VMS should be located such that the message to be displayed will have the most meaningful effect on the corridor.
· Dynamic signal control of traffic lights.
· Traffic information on the corridor and the road network in the immediate vicinity of the intersections,
· Route guidance via SMS, e-mail, telephone to drivers.
· Provision of traffic information via telephone service
· Traffic information via website.
· Pictorial view of traffic via mobile web service.
- Timing of Traffic lights.
a) Inadequate timings at traffic intersections create temporal build-up of traffic. Traffic does not clear from intersection for others to have their right of way.
b) Insufficient timing at pedestrians crossing to cross road double lanes get pedestrian caught mid the road. Sometimes the pedestrian volume is more than the capacity of the signal.
ICT Service Required for signal timing:
Dynamic traffic signaling with override control from the Traffic Monitoring Centre will be needed for effective signal timing.
- Attitudes of drivers
a) Jumping of red light: Drivers jumping of red lights by does result in accidents.
Motorcycle riders have the habit of disregarding traffic signals as if they are exempted. Pedestrians get knocked down at pedestrian crossings.
b) Use of road shoulders: Road shoulders are used by drivers to avoid traffic.
c) Delays in take off: Either through lack of attention at the wheel or the roadworthiness of the vehicle, sluggish takeoff of vehicles when the lights turn green results in less number of vehicles crossing than the design capacity.
d) Driving in wrong lanes and forbidden turns: Driving in wrong lanes occasionally results in forbidden turns, such as driving in outer lanes on approach to intersections with a final intent of leaving the intersection through a left turn results in the hold up of traffic until such a vehicle manages to leave the scene. This is indirect violation of the provision of safety measure by the Ghana Highways Authority that “Turning traffic should be separated out from the through traffic at major junctions in larger towns”. The police on duty on such occasions compel such drivers to drive straight on instead of turning left.
Also the Ghana Highways Authority safety provision that “pedestrian and slow-moving vehicles clearly segregated wherever possible” is violated by slow moving vehicles using the high speed lanes on the corridor. Even though the outer lanes have been designated as bus lanes, buses are seen in inner lanes.
e) Inter driver conversation: Bypassing drivers stop side by side on the road to converse with disregard to other road users.
f) Flouting of road regulation: Non-adherence to road signs, driving under the influence of alcohol, driving with inappropriate driving license, and the usage of defective vehicle and number plates.
Wrong parking: The capacities of bus bays along the corridor are not always able to contain the large number of user vehicles. The eagerness commercial drivers for more commercial activity occasionally result in vehicles quickly converging at a bus bay, either as a result of speeding or defiantly waiting in the quest of getting more passengers before leaving the bay. Some vehicles are compelled to park without clearance from the road. Others deliberately refuse to enter the parking bay in order not to be locked-in.
g) Over speeding: Over speeding results in vehicles quickly converging at traffic lights. Impatient drivers resort to careless driving in attempt to get off the queue. The sudden stoppage of vehicles at traffic lights results in vehicles rear-ending in chains.
ICT Service required for driver attitude monitoring:
Avenues must be created for information from the road users and the general public via telephone, e-mails or traffic website.
Video imaging must be used to monitor attitudes of drivers on the corridor.
Unwarranted stationary vehicles should be monitored over a prescribed period of time and alerts issued to appropriate authorities for intervention.
Speed must be monitored. Speed limit and/driving speeds must be displayed on Variable Message Sign.
Vehicle identification must be employed to report vehicle/driver incidents.
Lanes must be monitored to ensure effective and proper usage of separated side lanes.
Mechanisms must be in place for charging and collection of fines.
Monitored data should be stored for present use and archived for future reference.
4. Attitudes of pedestrians.
a) Pedestrians tend to cross at pedestrian crossing when they do not have the right of way. This results in pedestrians being knocked down by vehicles. It also has the effect of vehicles rear-ending each other as the one in front tends to stop for the pedestrian to pass while the inpatient driver at the rear tries to pull through, focusing attention only on the given right of way without ensuring that road is actually clear.
b) Pedestrians crossing when vehicles are not close in sight sometimes result in misjudgment of the speed of the coming vehicle. This occasionally results in accidents.
ICT Service required for pedestrian attitude monitoring:
Pedestrian presence detection must be used to allow crossing and also to ensure safe pedestrian clearance from the road.
Misconducts must be monitored by video and reported to the law enforcement agencies for action.
Mechanisms must be in place for charging and collection of fines as may be necessary by legislation.
Monitored data should be stored for present use and archived for future reference.
5. Other road incidents
a) Broken down vehicles. A broken down vehicle receiving attention on the road or being pushed away from the road results in temporal congestion.
b) Vehicle on fire: vehicle on fire causes a temporal congestion until the fire is put out and the vehicle removed.
c) Street hawking makes maneuvering difficult. This is worsening by the use of the street by some companies as their new product advertisement ground.
d) Cart pushers push their carts on the road with impunity and cause temporal traffic hold ups.
ICT Service required for driver attitude monitoring:
Broken down vehicles must be reported to the appropriate authorities for removal.
Vehicle on fire must be reported to the Fire Service Authority.
ICT can be used in granting emergency vehicles quick access.
Street hawking and unwarranted cart pushing must be reported to the appropriate authorities for clearance.
Mechanisms must be in place for charging and collection of fines as may be necessary by legislation.
Monitored data should be stored for present use and archived for future reference.
- Commercial activities around the Tetteh Quarshie interchange
This creates congestion which has extensive spillovers. The allotted parking lots get over flown into the interchange. Apart from the effects from vehicles, the human activities across roads in the interchange contribute to traffic congestion.
ICT Service required for commercial activity effect monitoring:
This will require more critical study, dialogue with business owners in the vicinity other than just simply ICT. The bus bay within the interchange and the pedestrian crossing there causes congestion and reckless driving.
ICT can be used in assisting pedestrian crossing. The involvement of commercial operators in the vicinity would be required as part of an institutional architecture
- Education
Some drivers drive to show lack of education in road user/driving regulations. Heavy vehicle drivers behave as if their vehicle size is equivalent to their authority over the road.
The ICT service required here would be for continued and intense road-safety campaign and driver and road user education.
- Migration.
Settlement in locations beyond Tetteh Quarshie Interchange has resulted in interspersed districts now merging extensively into the Akwapim range, on the Tetteh Quarshie Madina stretch of the corridor, and as far as Afienya and beyond on the Tetteh Quarshie – motorway stretch and beyond, and finally the Tetteh Quarshie - Spintex road stretch being no exception and merging seamlessly into the Tema metropolis. The consequence even at this stage where the Madina-Mamfi road construction is not completed is that vehicles speed a lot on the Manfi – Pantang Hospital Junction stretch that is a first class road, the portion that has been completed. This results in a lot of accidents at the Pantang Hospital junction where drivers tend to enter that section with high speed.
When the entire road is completed right through Madina to the Tetteh Quarshie Interchange, it is anticipated that settlement will increase in the Akwapim area and vehicles will speed up and congest at traffic lights and finally Tetteh Quarshie interchange to enter the corridor.
The situation even in the present uncompleted state makes weekend and Monday trips, from Adenta through Madina to Tetteh Quarshie into the corridor a site of much concern.
Conclusion
As long as organizations do not have residential accommodation for their staffs in the vicinity of their work places, the issue of settlement locations will continue to pressurize the corridor as people commute into the inner city.
The redesigning of the road networks will help very much. However, that cannot be done in isolation. The volume of traffic would continue to increase. Road users should have a way of knowing what is happening on roads, leading to places of immediate interest, so as to plan their routes before the trip.
From this study it can be said that there is congestion on the Tetteh Quarshie – Ako-Adjei corridor. Speed is a big issue in this regarded and of such a concern if even the police cannot contain it. The use of ICT would be required, especially with regard to the use of cameras to monitor the roads. This would help check attitudes on the corridor and to some extent, to assist in its decongestion.
The next chapter analyzes and designs the Traffic Monitoring System Architecture based on the findings of this case study. This system architecture, when employed, will be a piecewise step in the decongestion of the corridor by using ICT.
For further study, it is being proposed that the issue of decentralization of the major activities within the Central Business District and the use of ICT in governance be critically examined to further improve on decongestion measures in the city. The expansion of roads is also important here.