|
|
Planning | Design | Implementation and construction WAYS TO ADDRESS
COMMON EFFECTS TO LINEAR TRANSPORT INFRASTRUCTURE Introduction Code of Practice
Pointers – Adopt
an approach, which seeks to avoid, mitigate and compensate. In the first
instance consider the less harmful options. – Include
an early consideration of landscape and biological diversity within the planning
process. – Focus
on significant landscapes/habitats and species, for example resolving the
effects on threatened species; but do not overlook commonly occurring features
of the wider landscape. – Co-ordinate
schemes in transboundary locations. The benefits of
strategic and scheme environmental assessment have been discussed in section 3.
The planning of a scheme should aim to avoid sensitive valued landscapes and
habitats. Inevitably a balance is required with these and other factors. To
complete an assessment requires knowledge of the characteristics of the scheme,
the likely effects and the measures required to reduce the negative effects.
Examples of this type of information are summarised in Table 5.1 to 5.4. The
earlier the involvement of landscape and ecological specialists the easier it is
to accommodate changes to the engineering scheme, In the first instance least
harmful alternatives should be considered. Whilst initial
effort should focus on specially protected areas and species, still it is
necessary to consider more commonly occurring features which contribute to the
diversity of the locality, for example the type of field boundary. Positive
benefits can be achieved by co-ordinating the transport infrastructure with
adjacent land uses, for example to assist with the development of
landscape/habitat corridors (as suggested for the Pan-European Ecological
Network). Where schemes cross national boundaries differences in legislation can lead to a double standard and unnecessary confusion. Co-ordination is required and for practical reasons it is easier to adopt one set of standards. Other problems relate to the mismatch of a scheme either side of the border with one section/terminal unknowingly determining the alignment of the section in the adjacent state with potential repercussions for protected areas. These matters should be addressed during the planning stage Code of Practice
Pointers – Relate
scheme design and management to the character of the landscape/scenery and
biological diversity in the area. – Adopt
a flexible approach to engineering design standards/criteria to accommodate the
character and value of the landscape/habitat/species in the area. Consider the
appropriateness of standard solutions in the local context. – Be
reactive to opportunities for enhancement/maximising benefits, and minimising
disbenefits including fitting the scheme into the wider landscape and relating
it to the biological context. Roads are associated
with greater environmental effects than either rail or water transport but this
largely reflects the demand and associated extent of the network. In some
locations railways and waterways can be equally or more damaging than roads.
Strategic environmental assessment should help to draw out such major
differences as part of the evaluation of alternative solutions. At a much more
detailed level, the application of EIA to the design process
of the scheme should enable decisions to be taken to accommodate local
characteristics. The engineering
design standards of a scheme relate to the provision of safe conditions for the
user with consequential differences in landtake (Table 4.1). Thus the need for
gentle curves and gradients on motorways or high-speed trains (HST) have the
potential to cause a greater negative effect than a more local scheme. However,
larger schemes are associated with a greater need for funding and legal control,
including an EIA. Such control can regulate the need for the scheme and ensure
the quality of detailed design including adopting a flexible approach to
engineering and other design criteria and/or standards in order to accommodate
local features of landscape and ecological value. As new technologies are
developed the design will need to consider their environmental effects. Minor (local) and
upgrading transport schemes may be subject to fewer legal restrictions but can
cause significant negative effects, particularly in locations where the scale of
the landscape is small and the value of biological diversity high. Such effects
should be identified in an environmental impact assessment. This highlights the
benefits of following the environmental assessment approach in all cases. Table 4.1
Comparative land take for different design standards of road and rail
Source:
CEC 1993 Particularly in
degraded or intensively developed localities opportunities for the enhancement
of landscape or biological diversity can result from the construction of
transport infrastructure (Verheyden and Meunier, 1998). This can be more
successful when enhancement focuses on particular landscape features, habitats
or species. Other initiatives may be able to achieve such enhancement outside of
the transport corridor for example, agri environment schemes which change
agricultural practice. Implementation
and construction Code of Practice
Pointers – Pay
attention to detailed design with respect to the visual and ecological aspects
including the use of fauna-friendly designs. – Initiate/implement
procedures to enable the acquisition of appropriate land for environmental
mitigation. – Apply
best available technology including surface materials, feasibility of recycling
and recycling of materials/surplus spoil. – Assess
the environmental effects of siting construction camps, storage areas and future
associated developments, e.g. service station/marinas, maintenance depot. – Retain
specialists to monitor environmental compliance on site, including during the
construction period. – Inform
and involve local organisations/people in these stages. Land acquisition is
a crucial stage in the construction process. The procedures vary between states
but where possible the area acquired should include land needed to ensure the
implementation of mitigation and compensation measures. Without the acquisition
of such land there is no certainty that land occupiers will agree to the
proposed measures with a greater risk of consequential long-term environmental
problems. Available
information on the scheme at the approved time of submission for planning
approval can vary. The level of detail in the environmental impact assessment
can vary and also is mostly led by the engineering design including information
on ground conditions from the site investigation. Prior to construction work
there in is an opportunity for a further level of detail design where landscape
and ecological matters need to be re considered alongside engineering, for
example the design of the drainage to integrate with the setting or protect
wildlife including water balancing facilities, and the benefits of different
types of surface materials. Just before construction starts the need for
additional surveys should be considered, especially for species which may have
moved since the original surveys were undertaken. The best
environmental and cost benefits are achieved where there is a balance in the
earthworks i.e. cuttings and embankments. But this is not always possible, for
example site investigation may find that excavated material is unsuitable to
re-use for construction purposes and requires land for disposal. Knowing that
this is likely will assist the development of more sustainable solutions and the
application of best available technology. For example, using surplus or recycled
material to integrate the scheme into the landscape, or restoring borrow pits to
benefit waterfowl. The ‘need’ to import material can extend the ripple of
environmental effects of the scheme but is outside the scope of this Code. Transport
infrastructure differs from many other forms of development on account of its
linear nature and the associated extensive interface of construction works.
Earth storage areas/borrow pits and plant may be established along the route to
reduce haulage costs. Access for construction vehicles may require
widening/upgrading of the local transport network so spreading the environmental
effects of the transport line over a wider corridor. The fine detail of such
proposals may be known only at a relatively late date in the programme but at
the time of scheme approval can be controlled by the placement of “no go”
areas within and adjacent to the construction corridor. As an absolute minimum
it is important to locate sensitive areas in the corridor to avoid risk of
damage. Procurement and
contractual arrangements vary with the traditional separation between the
client, “designer” and the builder where the designer acts on behalf of the
client supervising the works. More recent arrangements include “design and
build” where the contractor is responsible for the detailed design and
construction to meet the overall objectives of the scheme. In this case, an
agent may represent the client. The agent checks that construction work is
implemented following procedures set out in a number of agreed method
statements. This approach can provide a closer relationship between those
advising on landscape and ecological aspects, and those directly undertaking
construction work. It requires the retention of specialists within the
construction team. The application of
Environmental Management, i.e. ISO 14001 (1S0 1996), enables the planning of
construction operations so as to reduce the environmental risk including
programming of work, for example, to relate to the seasonal requirements of
certain species, such as clearing trees outside the bird breeding season.
Compliance with legal requirements gives greater weight to the management system
and this in turn is fundamentally dependent on the robustness of the local
legislation and regulations. |
|
