E/1999/20
Distr.:General
9 April 1999
Original: English
Substantive session of 1999
Geneva, 5–30 July 1999
Item 10 of the provisional agenda
Regional cooperation
Project
for a Europe-Africa permanent link through the Strait of Gibraltar
Note by the
Secretary-General
1. The Secretary-General has
the honour to transmit to the Economic and Social Council the report prepared
in accordance with Council resolution 1997/48 by the Executive Secretaries of
the Economic Commission for Europe and the Economic Commission for Africa on
the work that has been done in connection with the project to establish a
Europe-Africa permanent link through the Strait of Gibraltar (see annex).
2. The Economic and Social
Council has taken an interest in this project since 1982 following a decision
by the Governments of Morocco and Spain to carry out joint studies on the
feasibility of the project as part of an agreement on bilateral cooperation
adopted on 24 October 1980. Since then the Council has regularly requested the
two regional commissions to keep track of the progress of studies relating to
the project and to inform the Council of any developments.
Annex
Project
for a Europe-Africa permanent link through the Strait of Gibraltar: report on
studies and activities carried out during the period 1997–1998
Contents
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Paragraphs
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Page
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Introduction...........................................................................................................
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1–5
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3
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I. Project studies and activities ..................................................................................
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6–18
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3
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A. Physical environment....................................................................................
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11–13
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4
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B. Engineering..................................................................................................
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14
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4
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C. Socio-economic aspects..............................................................................
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15–17
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4
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D. Evaluation....................................................................................................
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18
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5
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II. Other project activities...........................................................................................
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19
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5
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III. Future work...........................................................................................................
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20
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5
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Introduction
1. In its resolution 1997/48
of 22 July 1997, the Economic and Social Council requested the Executive
Secretaries of the Economic Commission for Africa and the Economic Commission
for Europe to take an active part in the follow-up to the project for a Europe-Africa
permanent link through the Strait of Gibraltar and to report to the Council at
its substantive session of 1997.
2. This report, drawn up
jointly by the two regional commissions, is in response to that request and
gives a brief overview of the progress made following studies carried out in
1997–1998. It also takes account of other project-related activities, in
particular activities organized further to Council resolution 1997/48 under the
joint auspices of the two regional commissions and the International Tunnelling
Association (ITA), a non-governmental organization in consultative status with
the Council.
3. It should be recalled that
studies designed to advance the project have been carried out jointly by the
Governments of Morocco and Spain since 24 October 1980, the date on which the
two Governments adopted a bilateral agreement on the subject. This agreement,
which was later expanded by a supplementary agreement of 27 September 1989,
formally establishes both Governments’ commitment to make a joint study of the
feasibility of the project, and stipulates the creation of a standing
intergovernmental Joint Committee, to be responsible for carrying out the
agreement, and two State companies, one in Morocco and the other in Spain, to
be responsible for conducting the studies. These companies, which have been
working alongside the Joint Committee since 1981, are, on the Spanish side,
Sociedad de Estudios para la Comunicación Fija a través del Estrecho de
Gibraltar (SECEG), which has its head office in Madrid, and, on the Moroccan
side, Société Nationale d’Etudes du Détroit (SNED), whose head office is in
Rabat. The studies are carried out either by the two research companies
directly, or through scientific institutions in the two countries, or national
or international firms of consultants and surveyors with which the companies
have concluded agreements or contracts for services.
4. Within the above-mentioned
institutional framework, the studies are being carried out in phases and
programmes of studies. The feasibility studies currently in progress are a
follow-up to the pre-feasibility studies which were completed in 1990. The
feasibility studies are being conducted in stages, the first of which was
completed in 1996. The feasibility studies conducted during the first stage
made it possible to select, for further study, a basic option for
implementation of the permanent link project, comprising a rail tunnel bored
beneath the sill of the strait.
5. This report, based on
reports submitted by the two research companies in 1997 and 1998 to the Joint
Committee, gives an overview of the studies and activities carried out in the
context of the project and of their objectives and results and the problems
encountered in implementation.
I. Project
studies and activities
6. In 1997 stage two of the
feasibility phase, “F2. Feasibility 2”, began. In this stage and as preparation
for the feasibility study on the basic option selected, work was to focus on
the following aspects: (a) deep drilling, the priority nature of which had been
emphasized; (b) an update and comparative analysis of construction cost
estimates; and (c) an update and comparative analysis of traffic
projections.
7. The deep drilling survey,
BUCENTAURO 97, was by far the most significant activity in 1997. The survey
results represented a turning point in the development of the studies. In fact,
contrary to expectations based on previous studies, the deep drilling survey
brought to light unexpected geological problems regarding the thickness of the
Quaternary filling in the subsoil of the strait. In places this proved to exceed
100 metres, that is, much more than the 25 metres previously anticipated, and
without there having been any certain determination of the maximum depth of the
Quarternary filling.
8. In the light of these
results, the two research companies, in July 1997, made the following proposals
to the Joint Committee:
(a) Closure of the “F2. Feasibility 2” stage
with the findings available at the end of 1997 and opening of a new stage
designated “F3. Investigation”, based essentially on clarifying the geological
problems encountered and extending knowledge of the Europe-Africa traffic
system related to the project, with a view to better consolidating long-term
traffic projections;
(b) Adaptation of the programme of work then
being carried out to the new situation, with a view to closing the stage in
progress and preparing the new “Investigation” stage.
9. These proposals led to two
work programmes established on the formal basis of closing the previous stage
on 30 June 1998 and beginning the new stage immediately afterwards. The
programmes of work are: (a) “Work plan for stage F3. Investigation”, which the
companies jointly submitted to the Joint Committee in December 1998, and (b)
“Work plan for conclusion of stage F2”, activities under which are summarized
in this report.
10. The following paragraphs
offer a brief description of the development of the studies followed by the
activities programmed in each area of the study process — physical
environment, engineering, socio‑economic aspects and evaluation; status
in December 1998; and results of each activity.
A. Physical
environment
11. Exploration of the physical
environment constituted the major element of the work carried out by the
companies, relating essentially to geotechnical, geophysical and geological
investigation by means of offshore drilling. In the geotechnical area, the work
carried out allowed completion of the investigation programmed in the
exploratory gallery at Tarifa in Spain and the exploratory shaft at Malabata in
Morocco. These structures were monitored during their construction in 1994–1995
and, subsequently, by means of recordings, until very recently. Although a
significant amount of geotechnical information was gathered, probably sufficient for the feasibility studies, a
vast field of investigation remains (hydrogeomechanical behaviour and natural
stress in the undersea terranes to be undertaken in the final stage of the
study process. In this regard on site investigation of the undersea terranes at
significant depths, accessible from the Malabata shaft, will make a valuable
contribution.
12. With regard to geophysical
studies, the programmed — and completed — activities comprised not
only new surveys, adding to the many geophysical surveys previously carried
out, but also a new attempt to evaluate the likelihood of success of advanced
(and costly) three‑dimensional (3‑D) seismic survey techniques to
investigate the geological problems occurring. The results obtained from the
tests carried out (acoustic measurement of the terranes in question and
reinterpretation of old multi‑channel profiles using advanced techniques)
are far from conclusive, which leaves the issue of the relevance of carrying
out a 3‑D survey open to debate.
13. The 98 deep drilling
survey — incontestably the most significant activity in the work
programme — began in November 1998 and continued into 1999. In addition to
activities undertaken in preparation for the drilling contract itself, the
companies carried out preparatory activities included in the programme of work
so as to reduce, as far as possible, the principal technical difficulties
presented by the extraordinary system of sea currents in the straits. As a
whole these preparatory activities produced satisfactory results and lowered
the significant risk attaching to the drilling survey. The most noteworthy
aspect of the results of the survey (March 1999) is that, despite progress in
operational terms, which resulted in a near doubling of the maximum penetration
achieved in the previous survey, the geological substratum sought in certain
critical areas in the central part of the strait has still not been detected.
On the other hand, the survey provided fundamental confirmation of basic
geological hypotheses, which should lessen the problem and allow it to be
clarified in future studies.
B. Engineering
14. Engineering activities were
limited to revision of the preliminary pilot project for the basic option,
adapted to a new reference profile which, with a gradient of 30:1,000 would, in
theory, allow the geological faults detected by the BUCENTAUR 98 survey to be
avoided, while maintaining the length of the tunnel and the emplacement of the
terminals. The results are satisfactory in terms of the feasibility of using a
steeper gradient (25 to 30:1,000) as well as the increase in construction costs
as a result of using the gradient (11 per cent). These results confirm the
findings of the 1997 preliminary study, which had previously anticipated the
viability of steeper gradients with a moderate increase in costs (a gradient of
around 35:1,000 and a cost increase of 14 per cent).
C. Socio‑economic
aspects
15. Most of the socio‑economic
activities programmed were completed. Besides the maintenance of the
socio-economic and traffic database in the study area, work focused on
implementation of the specific recommendations of the Joint Committee on
increasing knowledge of traffic and long-term projection methods. This involved
traffic flow monitoring and recalibration of the TRATAR-95 model.
16. Traffic flow monitoring
activities related, as planned, to setting up a system of origin/destination
surveys for Europe-Africa traffic in strait ports for one year (August
1997–August 1998), on the basis of between 2,000 and 3,000 enquiries per month.
This operation is of great importance for calibration of the traffic models,
and was carried out with the cooperation of the port authorities of Algeciras,
Tangiers and Ceuta, which have also offered their cooperation in continuing the
system of surveys and in establishing other traffic flow monitoring elements.
17. Recalibration of the TRATAR
model, with a base year of 1995, provided updated long-term projections in the
study area, across the strait and across the fixed link. The results, in terms
of traffic volume, confirmed previous results, although with slightly lower
values (around 90 per cent) for passenger traffic and a steeper drop (80 per
cent) for toll receipts. A new element introduced by the TRATAR-95
recalibration, however, is the high level of responsiveness of goods traffic
over a fixed link to changes in the cost of transport by sea. As a result, a likely
cost reduction of, for example, 30 per cent would reduce traffic by 70 per cent
(rather than the 35 per cent estimated in previous studies).
D. Evaluation
18. Activities programmed under
this heading related essentially to updating the economic‑financial
evaluation of the basic option and preparation of the end-of-stage report on
the stage soon to be closed. These activities are still being carried out, and
will be completed in 1999. They will relate to the amended basic option, in
accordance with a recent revision of the pilot project. It should be noted that
the delay will not affect the substance of the study process given the formal
nature of the activities and the fact that it is not related to the next,
“Investigation” stage. Further, the impact of the current amendments on the
economic and financial evaluation is being monitored by the companies’
technical services, without significant risk that the current evaluations will
produce unexpected results.
II. Other
project activities
19. A series of other
activities has been undertaken or organized in the context of the project
pursuant to Economic and Social Council resolution 1997/48. These activities
include the organization, under the joint auspices of the regional commissions
concerned and ITA, of a workshop on characterization of tunnel boring machines
for tunnelling flyschs, held from 20–22 February 1997 at Tarifa, Spain, and a
workshop on costs of tunnels bored with tunnel-boring machines (TBMs),
scheduled for 22–24 April 1999 at Rabat, Morocco.
III. Future
work
20. Studies on the fixed link
project across the Strait of Gibraltar entered a new, F3. Investigation, stage
of the feasibility phase, necessitated by the unexpected results of the 97 deep
drilling survey. The results of this new stage will be decisive in improving
geological knowledge of the undersea terranes of the strait and thus for the
conduct of the project feasibility study.
