Lecture 10:The Problem of Traffic Congestion скачать в хорошем качестве

Lecture 10:The Problem of Traffic Congestion

The video looks at the problem of traffic congestion and how it affects the flow of traffic and also how it causes externalities on both road users and non road users. Many countries have to contend with the problem of traffic congestion especially in large cities and during peak hours. The problem has been increasing with growing ownership and driving of private cars. Traffic jams are time, and resource, wasting and frustrating and can lead to health problems. Congested roads inconvenience pedestrians, lead to increased road accidents, fuel pollution, and encourage breaking of the law and impact negatively on public transport. Traffic congestion is a condition on road networks that occurs as road use increases, and is characterized by slower speeds, longer trip times, and increased vehicular queuing. Congestion occurs when traffic demand is large enough for the interaction between vehicles to slow the speed of the traffic, and, sometimes, bring traffic to a complete stop. It is caused by there being too many vehicles especially cars but also lorries, all seeking to use road space at the same time. Road Traffic has been rising exponentially while the length of public roads has been increasing at a snail’s pace. Road Passenger kilometers using cars, and freight tonnage kilometers using trucks have been rising fast in recent decades, while those made by buses, or rail have been falling in many parts of the developed world. Motoring costs are now an increasing percentage of household expenditure. To economists, traffic congestion suggests a misuse of space. The demand for road space is high because the cost involved considers mainly the private costs of the motorists: fuel, vehicle maintenance, and time; and not the social costs imposed on others. Therefore, use of road space is underpriced. Efforts have gone into determining and bringing the marginal private cost, to the level of marginal social cost. Determinants for demand and supply for road space are discussed. Joining a road creates externalities which are: User to user externality: impacting negatively to other road users by slowing down speed for all User to non user externalities: Pollution, noise, inconvenience to pedestrians, society; negative impact on public transport; increased accidents. Individual motorists normally do not take externalities into consideration. Thus the need for public intervention. In developing countries we see the growth of car ownership, fueled by cheap second hand cars from developed world in a situation of huge infrastructure deficits. Good quality roads are few, and are not well networked or maintained. There is frequent breakdown of road infrastructure eg traffic signals, road signs; there is poor discipline on the road, with drivers outdoing each other; there is poor enforcement of road traffic regulations; Frequent traffic interruptions due to accidents, and the passage of VIPs. Car ownership and use still low, and may not be the major cause of traffic congestion in SSA cities. Car ownership: is desired by many but levels of income are low to allow this ownership and use. Average Modal share of: informal collective transport (minibuses – daladalas, collective taxis) = 34%; Non-motorized transport (walking and bicycling) = 40%; private cars, 12%. Thus, congestion is caused: limited, poorly designed and networked infrastructure; poor land use planning; road use indiscipline; and chaotic public transport. This suggests a need for more good roads which are better networked to disperse traffic; better land use planning to reduce urban sprawl and allow the dispersal of economic and social activities nodes; well knowing however, that more highways generate their own traffic in the long run. Thus there is need to work for efficient and convenient public transport. In all these endeavors, collaboration with the private sector is essential to muster resources. There is also need for public education, to encourage a more orderly use of roads, as well as a more orderly use of the informal public transport that there is.