5. Transport and traffic planning

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1. Scope

1.1 Definition of "Transport and Traffic"
1.2 Forms of transport and traffic

2. Environmental impacts and protective measures

2.1 Direct environmental impacts of principal transport modes
2.2 Direct protective measures
2.3 Environmental impacts of transport and traffic at local, regional, and global levels, and protective measures which can be applied
2.4 Reduction of road traffic and conversion to other transport modes, by means of regional development planning and a national transport and traffic plan
2.5 Administrative, regulatory and financial measures
2.6 Particular features of urban transport planning
2.7 Environment-oriented transport planning

3. Notes on the analysis and evaluation of environmental impacts3

3.1 Identification and analysis
3.2 Evaluation
3.3 Participation by third parties

4. Interaction with other sectors

5. Summary assessment of environmental relevance

6. References

1. Scope

1.1 Definition of "Transport and Traffic"

Transport and traffic serve the purpose of relocation of people and goods, as well as the conveying of information. The demands imposed on transport and traffic result from the interaction of those areas where people live and where commerce and industry are located, which are interlinked at many different levels and which are

- influenced by the number of inhabitants, the structure of human settlement, the general economic standard, the economic-geographical circumstances (such as natural land-use potential, the location of raw materials and production facilities), the production strategies (e.g. just-in-time), and by natural peripheral conditions (the topography),
- a consequence of economic policy (e.g. industrial settlement, the demands of the agricultural sector) and development planning (national development and regional planning), which can be used to control the transport and traffic demand through centralisation and decentralisation.

The type and intensity of transport and traffic depend on

- existing transport facilities
- operational measures (transport control systems)
- decisions relating to transport and traffic policy (tariffs, taxes, laws, state cooperation in the transport sector).

Motorised and mass transport in particular cause direct damage to both human beings and the environment; in addition, it can also contribute to disproportionate utilisation of resources, and so indirectly cause severe environmental problems [1].

1.2 Forms of transport and traffic


In many countries, the importance of road transport is predominant. Roads and highways are not only used by private cars and heavy goods vehicles, which cause the greatest environmental and safety problems, they are also used for movement and transport

- on foot
- by cart and barrow
- by bicycle
- by motorcycle.

The road is therefore a highly flexible carrier of vehicles representing different modes of transport and propulsion systems, though this may lead to a greater number of accidents.

In out-of-town areas, the road essentially serves the function of assisting in development and communication. A characteristic feature of the supra-local road and highway network is its gearing to those areas of population density in which economic development is concentrated. Environment-oriented planning is heavily biased towards natural geographical considerations.

Within populated areas, the road predominantly serves the needs of human habitation and communication, with the result that, in this situation, different user requirements are superimposed on one another.


As well as conveying people, railways are used mainly for the transport of mass goods (such as raw materials, fuels and crops) over long distances between economically significant node points, without frequent loading and unloading. In many countries, the efficiency of the railway system can only be maintained with difficulty, or is even falling. As a result, railway transport is losing significance, while from an environmental point of view it should in fact be being promoted. Economic railway operation should in particular be possible as a form of direct transport over long distances (e.g. between raw material sources and ports or metropolitan centres).


Shipping waterways (whether inland or otherwise), along the coasts and on rivers are widespread in the case of island nations and in regions with only minor altitude differentials (such as South-East Asia), and in remote regions are often the only means of transport available. In addition to local routes linking neighbouring areas of settlement, distinct traditional long-distance links are also found in these places; they are, nevertheless, losing ground to faster methods of transport by road. Specific energy consumption can be very low, even with motorised craft. As with road transport, different types of transport and methods of propulsion are possible, and uncontrolled juxtaposition of different modes entails a high risk of accidents.

Other transport and traffic systems

Other transport and traffic systems worth mentioning, which in many countries play a minor role overall but may well be of great local significance, are:

- air transport (aeroplanes, helicopters, and possibly even airships)
- pipelines for the transport of liquid or gaseous fuels (crude oil, mineral oil products, natural gas, liquified coal)
- cable railways, e.g. in raw materials projects (timber and ore extraction)
- telecommunications networks, which may in part replace the physical conveying of messages and information.

With the construction of new transport routes and the development of existing ones, the primary goal is to link different regions in a new or improved manner, and in this way to expand the market for the raw materials or finished products available in those locations. The intention is that the economic situation of people living in these regions should be improved by the higher levels of employment which are brought about. Very often, as a secondary effect, an improved supply of goods and services from outside the region may also be looked for.

Planning transport routes is aiming increasingly towards the maintenance and support of those which already exist, as well as their further development and the creation of new routes and systems.


2. Environmental impacts and protective measures

2.1 Direct environmental impacts of principal transport modes

The following summary of the direct environmental impacts of the principal transport modes is derived from the OECD report on Transport and the Environment [2]. This report expressly includes death and injury due to accidents as direct damage to human beings.

These effects occur not only during operation, but also

- during the establishment and development of the transport routes themselves,
- in the creation and disposal of facilities or vehicles which are no longer required,
- as an undesirable consequence of the opening up to traffic of areas which were formerly protected, through uncontrolled settlement.

Most environmental burdens are caused by motorised forms of transport, and by vehicular traffic in particular. In certain circumstances, however, even traditional modes of movement can result in environmental damage; for example, in mountainous areas, over-used footpaths may contribute to erosion.


Figure 1 - Direct environmental impacts of principal transport modes [2]

Principal transport modes


Water resources

Land resources

Solid waste


Risks of accidents

Other impacts

Marine and inland water transport


Modification of water systems during port construction and canal cutting and dredging

Land taken for infra-structures; dereliction of obsolete port facilities and canals.

Vessels and craft withdrawn from service


Bulk transport of fuels and hazardous substances


Rail transport


Land taken for rights of way and terminals; dereliction of obsolete facilities

Abandoned lines, equipment and rolling stock

Noise and vibration around terminals and along railway lines

Derailment or collision of freight carrying hazardous substances

Partition or destruction of neighbour-hoods, farmland and wild life habitats

Road transport

Air pollution (CO, HC, Nox, particulates and fuel additives such as lead) Global Pollution (CO2, CFC)

Pollution of surface water and groundwater by surface run-off, modification of water systems by road building

Land taken for infra-structures; extraction of road building materials

Abandoned spoil tips and rubble from road works; road vehicles withdrawn from service; waste oil

Noise and vibration from cars, motorcycles and lorries in cities, and along main roads

Deaths, injuries and property damaged from road accidents; risk of transport of hazardous substances; risks of structural failure in old or worn road facilities

Partition or destruction of neighbour-hoods, farmland and wild life habitats, congestion

Air transport

Air pollution

Modification of water tables, river courses and field drainage in airport construction

Land taken for infra-structures; dereliction of obsolete facilities

Aircraft withdrawn from service

Noise around airports


Pipelines (according to [3])


Pollution of groundwater by leakages


Access roads and air strips and its impacts

A detailed description of the environmental impacts of road, rail, air, and water transport can be found in the relevant environmental briefs. The relevant guidelines from the ADB [4], the ODA [5], and the World Bank [3] also provide a good overview of the environmental impacts from the transport and traffic sector.

2.2 Direct protective measures

Countermeasures can be grouped into the following categories:

I) the establishment of "low-conflict corridors" (route planning and location selection with the lowest possible environmental impact and low accident risk, and the grouping of routes to keep clear of areas which require protection)

II) space-saving, non-eroding and safe layout of transport routes

III) technical measures for reducing emissions from motor vehicles (such as incentives for vehicles with low noise and exhaust emissions, and inspections of the technical condition of the vehicle)

IV) proposals for methods of operation which help preserve the environment and reduce the risk of accidents (e.g. speed regulations)

V) structural and traffic guidance measures (such as spatial and temporal access restrictions in urban areas, preference for public transport in towns (bus lanes), preference for commercial transport essential for the life of the town or city (such as keeping loading areas clear), preference for well-filled private cars (car-sharing), and safety precautions in water conservation areas.

2.3 Environmental impacts of transport and traffic at local, regional, and global levels, and protective measures which can be applied

The background to taking due note of environmental impacts is the principle of the permanent safeguarding of ecosystems, for the long-term securing of the basic essentials for human life. The risk posed to this by transport and traffic can be considered on three levels:

I) The immediate human environment:

The demand for space for transport routes, and the contamination of soil and drinking water can pose a risk to the basics of both living areas and foodstuffs. Likewise, the killing of domestic animals by road vehicles can be regarded as a considerable impediment to human wellbeing. This gives grounds for the selection of less space-intensive and more emission-free means of transport, in order to achieve routing arrangements which help save space and reduce speed, as well as the introduction of safety measures on the vehicles, traffic education, and the monitoring of both vehicles and drivers.

II) Many countries possess extremely complex and fragile ecosystems, which in addition have been far less investigated than the comparably stable ecosystems of the temperate zones (see [6]). Assaults on the soil and hydrological balance and on the animal kingdom by transport routes are accordingly even more difficult to appraise with regard to their interactive and long-term effects, and are thus to be treated even more cautiously.

In this context, too, consideration should be given to the ecological harm caused by the indirect consequences of transport routes, and of roads in particular, which include

- more intensive agricultural land-use
- the creation of forest aisles for raw materials projects
- unplanned woodland clearance
- and the threat to animal species which are already endangered.

The following measures to reduce these risks are proposed:

- regulations for monitoring land-use in the project regions and efficient supervision
- reinforcing the efficiency of the state supervisory bodies, such as the forestry or national parks administration, by improving training, staffing, equipment, prestige, and legal status
- the development of a rural consultancy and credit system for promoting ecologically adapted and sustainable agricultural land-use
- limited use of roads by specific groups of people (e.g. tourists) and vehicles (heavy goods vehicles)
- the establishment of a Department of the Environment, with sufficient influence among the transport authorities
- the promulgation and implementation of environmental protection laws.

III) The greenhouse effect and the depletion of crude oil reserves are proving to be of global significance. CO2 emissions and the consumption of mineral oil by today’s transport systems will reduce the scope for other CO2 emitters and oil consumers, such as industry, power stations, and the private sector, with limits being imposed on national emission levels under international agreements, and these restrictions may prove to be a brake on development. In this context it should be noted that CO2 emissions, by contrast with other air pollutants (such as nitrogen oxides or hydrocarbons), cannot be reduced by adding devices to vehicles with internal combustion engines (such as catalytic converters).

Moreover, reductions in the diversity of species, particularly in the tropics, which may result from the effects of transport and traffic, are also regarded as a long-term threat to humanity as a whole: Transport routes which cut through areas which have been designated as nature preserves may seriously impair the habitats of animal and plant species and may lead to their decimation [7]. Railway lines are less divisive because they provide the same transport capacity with smaller route cross-sections and lower frequencies than long-distance highways; protection of the areas which remain, along the lines of a nature park scheme, such as that proposed by the World Bank [8], may prevent further reduction of stocks through uncontrolled clearance and human settlement (see II).

2.4 Reduction of road traffic and conversion to other transport modes, by means of regional development planning and a national transport and traffic plan

Vehicular road traffic is the worst of the environmentally-harmful modes of transport. In particular, the specific pollutant emissions and energy consumption of heavy transport is many times that of rail or ship transport, with the same degree of utilisation; moreover, roads inflict more damage on the ecosystem than rails because of the larger surface area required and because of erosion. The more important it is, then, to adopt transport and regional developing planning methods which will reduce road transport in absolute terms or bring about a change to less environmentally harmful modes of transport. This can be achieved in the following ways:

I) Decentralisation of housing, industry and utilities, with a view to shorter transport distances (while preserving minimum distances from emission sources; see environmental brief Spatial and Regional Planning).

II) A shift away from heavy goods vehicles to less environmentally harmful modes of transport, particularly rail (and possibly water) transport, is a desirable goal. At the present time, however, the advantages of road transport (relative reliability and punctuality, particularly important in the case of perishable goods, fewer formalities, less risk of theft during loading and unloading) overshadow other considerations, even though lorry freight charges may be higher, and even lead to goods being carried by road parallel to railway routes. Reversing this trend will require a substantial improvement in the poor technical and organizational condition of railway facilities, most of which are run by the state.

Appropriate measures such as container transport, combined transport techniques, decentralised goods distribution depots and information systems for optimum interlinking of road vehicles and rail/water systems may not as yet be adequately established in most countries, but should likewise be explored and encouraged. The transport of hazardous goods at least (fuels, other explosive substances and corrosive chemicals) should be moved as far as possible away from the roads and onto ship and rail transport, provided this is not also dangerous. Transport planning should make provision for the future creation of goods transfer points and road connections for them, as an adjunct to programmes of expansion and new construction.

III) For simply structured transport tasks, as in the case of raw material projects, special transport systems such as pipelines, narrow-gauge railways, or cable railways may be not only less damaging to the environment, but also more economical than heavy goods vehicles. In particular this might also serve to counter the major hazards of uncontrolled settlement and the destruction of natural areas through excessive road-building.

IV) Increased attraction of the "environmental combination" (foot, bicycle, cart, bus), for example in the form of independent tracks and priority regulations, assured by construction measures, especially in local areas.

V) Environment-oriented transport planning also means the restriction of vehicular transport in regions with heavy environmental burdens or which are ecologically sensitive, by halting new construction or expansion programmes, or even by removing a certain number of roads.

It is necessary to see how future changes in the nature and extent of transport demand will have an influence on the environmental effects of the planned transport modes:

Thus, a purely volumetric increase in rail transport demand can be largely met by lengthening train units, while in the case of road transport and air traffic, this would mean a sharp increase in the number of vehicles, and therefore in the environmental burden.

On the other hand, a decrease in transport demand or a change in the periodic pattern of demand, the type of goods being transported or the source-destination relationships may, in the case of rail transport, lead to lower capacity utilisation, so that at least the environmental burden (and also the costs!) per ton or per passenger transported would rise. As a consequence, it is recommended, in cases in which the future requirement volumes and structures are uncertain, that the choice be for means of transport which are comparatively flexible, but still as environment-friendly as possible (narrow-gauge railways, cable railways, coastal and inland waterways, electric vehicles and vehicles using overhead power lines in countries with hydroelectric power supplies).

2.5 Administrative, regulatory, and financial measures

Administrative, regulatory, and financial measures can also help attain a reduction in the volume of road traffic and the associated environmental burden and a transfer to less environmentally harmful transport modes:

I) Mineral oil taxes and levies can appreciably increase the variable costs of more vehicles, resulting in

- a higher degree of utilisation (and therefore fewer journeys)
- more economical travel,
- technical measures for reducing fuel demand (and therefore fewer emissions),
- greater competitiveness of rail and water transport.

This would also result in a part of the external (environmental damage) costs of road transport being absorbed. During a transitional period, part of the additional revenue received by the state could be paid back by reducing the largely fixed outgoings, e.g. by reducing customs duties on spare parts.

II) Regulations and fiscal incentives for improving exhaust gas values:

Introduction and preferential taxation of lead-free petrol, exhaust gas and soot standards for new vehicles, higher vehicle tax for old vehicles.

III) Approval, extension, and expansion of transport concessions subject to fulfilment of environmental requirements such as

- motor vehicle inspections,
- transport by rail and ship,
- driver training,
- rules on driver working hours (to avoid accidents).

IV) Tariff calculations of state railway and shipping bodies geared more towards variable costs, leading to specific cuts in rates for large transport volumes and/or long distances. This will help improve competitiveness as compared with road vehicles.

V) Appropriate timing of events or activities which produce severe concentrations of traffic especially in built-up areas (such as sports or political events, or the start of work or school). The effect is however limited, as experience with flexitime arrangements in industrialised countries has shown.

VI) Education of transport users. It is important for politicians and administrators to set an example by using, say, bicycles or mopeds, or travelling on public transport in the course of their duties (the personal experience of decision-makers can lead to these transport systems being improved). The brochure of the UK Department of Transport [9] describes a successful example.

2.6 Particular features of urban transport planning

Special conditions prevail in urban areas and the following key topics may be mentioned in this regard:

- Improvements in the telephone network and other modern data transfer systems (such as fax machines) may help avoid journeys which serve only as a means of communication (NB: The effect of telecommunications on transport growth is still not entirely certain. The indications are, however, that telecommunications will not replace "physical" transport to any extent worth mentioning, since the increased communication will in turn boost the need to make journeys, taking the place of the "substituted" traffic.
- highway crime (this is a reason for using vehicles)
- (re)introduction of trams to cope with major commuter flows in urban areas
- promotion of the "environmental combination" (see 2.4 IV).

2.7 Environment-oriented transport planning

Transport planning should be regarded as a process of harmonisation between the economy, society, and the environment. On the one hand, transport serves the purpose of meeting basic supply and mobility needs and thus promoting the material welfare of the country; on the other hand, the long-term sustainability of life’s essentials must not be overlooked.

Accordingly, national development and transport planning and additional regulatory measures must create the conditions for achievement of the desired living standard,

- with minimal transport demand,
- with environment-friendly modes of transport (rail, ship) accounting for the largest possible proportion of total transport volume,
- using routes which avoid or protect especially sensitive transport corridors,
- with vehicles in satisfactory condition, such that pollutant and noise emissions and energy consumption are kept to an absolute minimum,
- using vehicles in such a way as to ensure that the number and severity of accidents as well as noise, pollutant emissions, and energy consumption are kept to a minimum (e.g. through speed restrictions or rules on driver working hours).

In order to make these goals a reality, transport planning must look to the future, and be integrated into the overall planning picture, paying particular attention to the way it interacts with town planning, regional development planning and also landscape planning. Parallel development of different, competing transport modes needs to be avoided as far as possible, as this not only causes environmental problems (additional demand for space, higher emission levels due to road transport), but is also uneconomical. The main aim should be to make optimum use of the specific advantages of the individual transport mode (road transport: flexible operation with full area coverage; rail: point-to-point transport over long distances and over shorter distances along transport axes; ship: for transport where speed is not an important factor, transport of heavy goods). This often involves cooperation between different forms of transport and requires a fully functional and reliable cargo transfer system.

Environment-oriented transport planning therefore involves not only the construction and development of transport routes, but also and in particular administrative and regulatory measures and harmonisation with other development plans.

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