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Taxonomy and description Terminology An efficient system of road freight transport is very important for any economy. All sectors of business rely on a complex flow of raw materials, components and finished goods. Society, however, perceives lorries as a nuisance which can have several detrimental effects, such as noise, environmental intrusion and damage to infrastructure. This had led to the development of numerous lorry management techniques, aimed at reducing the nuisance. A Lorry, or ‘heavy commercial vehicle’ (HGV), is defined as any goods vehicle with an operating weight, (i.e. gross permitted weight) exceeding 7.5 tonnes. They are sub-divided into the following groups:
Many of the measures which can reduce the environmental impact of lorries require legal procedures to be followed for their implementation. Section 2 of Traffic Regulation Act 1984, is concerned with amenity control on goods vehicles, which local authorities may introduce, which include:
Types of Lorry Routes and Bans Lorry Routes Control of through routes relates to Positive routeing, i.e. specifying mandatory through routes for lorries. However, through experience, it has shown that mandatory routes are not very practical. Drivers understanding and compliance is likely to be very poor, and signing of the routes can be very complex. Therefore many authorities have changed their approach to negative routeing, i.e. specifying roads and zones which are prohibited to lorries but subject to exemptions, such as unloading. Advisory routeing for lorries is now widely used. The proportion of lorries in a large conurbation on a through trip is generally small. Controls used in smaller conurbations are not always suitable for larger conurbations in reducing overall environmental disturbance, lorries in larger conurbations will re-route into adjoining areas. A total ban of vehicles passing through the conurbation would also affect a small proportion of the flows. Successful routeing controls depend upon the existence of a suitable network of purpose-designed roads which are able to accommodate increased lorry flows (the lorries displaced from adjoining areas). Previous experience has shown that concentrating lorry flows on to a small number of roads, some of which may be environmentally sensitive, may not be acceptable. Therefore the roads identified for an urban lorry network are likely to be busy roads with poor existing environmental conditions. Lorry management is not only about regulating, restricting or banning lorries. It can also be used to assist lorries to become more efficient, for example by improving access to, and circulation within urban areas. The more efficiently lorries and industry operate then the likelihood is that less lorries will be needed. However, the inefficiency and unreliability of road networks, combined with over-restrictive control measures, can increase lorry traffic. Positive lorry policy is likely to yield environmental and economic benefits. Low cost improvements can often reduce or eliminate difficulties incurred by lorries when using a sub-standard junction. For example, Newcastle City Council has introduced a shared bus and lorry lane (photograph 25.1) at Barras Bridge to help essential passenger and goods movement. In London , no-car lanes are under development for certain routes. Where bus usage in insufficient to provide an exclusive bus lane, a shared bus and lorry lane may be considered. A number of authorities have introduced local advisory routeing schemes, which identify preferred routes for lorries entering town centres, industrial estates, retail parks and other areas of significant lorry build-up. The area is usually divided into zones; with the preferred routes serving each zone codified a letter, number, symbol or colour, and hence signed appropriately. To be a success, such schemes need good publicity and coverage, (i.e. information displayed in the form of maps and leaflets), and co-operation of local firms (i.e. advising their suppliers). Lorry Bans Lorry bans can be enforced in several ways, including physical barriers. Although physical barriers are non-regulatory, i.e. self enforcing, they do require a Traffic Regulation Order (TRO) if placed on the highway, as they will prevent the passage of vehicles otherwise lawfully allowed. The simplest physical measure is a height-limiting barrier, although this is used only to give advance warning ahead of physical restrictions, although they can be useful for preventing access for oversized vehicles. Physical width restrictions may be narrowed to less than 2.5m at selected points to prevent to the passage of large vehicles. Width-restrictions can effectively create cul-de-sacs without turning space so large vehicles become trapped and may have to reverse for long distances. It is essential that they are located intelligently and signed well in advance. Using the UK as an example, the Road Traffic Regulation Act 1984 gave local authorities wide-ranging powers to local authorities to regulate traffic. Many local authorities have taken powers under the Act to protect sensitive parts of the highway structure from the effects of heavy lorries, for example, prohibiting them from using weak or low bridges, using both regulatory and advance warning signs.
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