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APPLYING THE
CODE; COMPARATIVE EFFECTS AND SOLUTIONS Introduction By way of
illustration, this section makes comparisons between the effects associated with
roads, rail and navigable waterways and suggests solutions applying principles
of the Practice Pointers relating to landscape and biological diversity. Further
detail is included in the specialist technical reports (Appendix). Tables 5.1 to
5.4 located at the end of the section provide a comparative summary of much of
the information. Context There are a number
of essential differences between roads, railways and waterways. The context for
the differences needs to be understood particularly when considering modal
choice (Table 5.1). Roads Possibly on account of the extent of the
road network, the associated implications relating to landscape and biological
diversity have been studied in greater detail than for rail or waterways. The
road network is well-documented and characteristically hierarchical including
ancient lanes a few metres wide with occasional use. At the other extreme are
motorways with numerous lanes in each direction with rapid movement of traffic,
although occasionally it can standstill on account of the lack of traffic
capacity. Continued building of further roads is
not an automatic solution to congestion and more radical solutions are being
sought, for example road pricing, modal split. In other cases roads are
associated with specific types of development, for example the short-term
abstraction of timber or minerals, or military objectives, or to benefit
tourism. Apart from obvious differences in the
hierarchy such as the dimensions and the level of use, other differences relate
to characteristics of interchanges (nodes) and (Table 4.1) associated
facilities. Usually motorways have minimum curvature and gradients, junctions
are grade separated often with lighting, service stations and resting areas are
integral, the motorway is fenced and users are restricted i.e. no horses or
learner drivers. Local roads may include sharp bends and steep gradients, have
few crossing or entry restrictions, need not be fenced and generally service
areas form part of adjacent development i.e. alongside housing etc. Such
differences can have consequential implications with respect to the effects on
landscape and biological diversity including those resulting from cumulative
effects. Railways The extent of the
European railway network is considerably less that that of the road network. The
turn of the 21st century heralds a period of growth with
technological advancements enabling faster trains with associated upgrading or
construction of new tracks and rolling stock, and intermodal facilities. Rail
freight is being encouraged to revitalise. A number of abandoned tracks are
being re-opened for recreational purposes, for example cycle routes; as well as
for new roads and commercial rail traffic. A typical cross
section width of a railway is about half that of the equivalent road (Table
4.1). Most lines are associated with additional land for sidings, maintenance
depots and stations. Generally the line is accompanied by overhead cables and is
fenced. Crossing points are either at
grade (level) or grade separated. High-speed trains require the most stringent
standards of track with implications for the horizontal and vertical alignment. Waterways Inland navigable
waterways comprise canals and navigable rivers. After an early expansion in the
Industrial Revolution waterways were unable to compete with railways and later
road freight. Subsequently recreational uses developed. Other uses of canals
relate to drainage, routes for telecommunication cables and water transfer. The
multi-purpose use of waterways distinguishes them from roads and railways. Within the
pan-European region the extent of waterways is a fraction of both the road and
rail network. However, the waterway network plays a greater transport role in
some lowland states and in the lower reaches of large rivers it is the main form
of access, for example in parts of northern Siberia. In the Netherlands about a
fifth of the total inland freight tonnage is conveyed by boat and half of the
5000 km of waterway is available for boats over 1000 tonnes but even here much
of the network is used for recreational purposes. In contrast, in England and
Wales well over half of the waterways are either abandoned or not navigable (DETR
2000); navigable sections contribute to the carriage of one percent of the
domestic freight. The carriage of
freight along larger navigations seems set to continue and the size requirements
of the industry increase, with implications for the upgrading or construction of
new navigable waterways. Large vessels set the requirements for other users (Bekker
G et al 1991). Canals are
artificial in origin although some have developed from watercourses; in contrast
navigable rivers are natural. Compared with road and rail, the alignment of
canals has the least flexibility due to the need to maintain the same level.
This has resulted in some dramatic aqueducts as well as extensive embankments.
Locks provide the means of descending slopes. Their width determines the maximum
width of boats using the waterway. As with roads and railways some features on
canals can be of historic or landscape importance e.g. aqueducts and pump
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