[322/03] Francke - Ingenia

INFRASTRUCTURE
Figure 2: The route of the Øresund Bridge
ingenia
The skill with which the contractors
successfully planned and executed the
construction of the tunnel, the bridge
and the major dredging works can
largely be ascribed to the Design-and-
Construct concept which forms a part
of all the major contracts. Optimum use
of prefabrication also played a key role.
As the Design-and-Construct concept
lays down precise functional
requirements for the whole project,
contractors are responsible for the
detailed design as well as for the
construction work.
Rigorous environmental requirements
were in force throughout the
construction period, governing both the
construction of the link and the impact
of the completed link on the
surrounding environment. As the Danish
and Swedish governments had
stipulated that the link must not block
the water flow through Øresund, careful
trimming of the link’s design reduced
the calculated blocking effect from 2.3
per cent of the water flow to 0.5 per
cent prior to final adjustment.
Compensation dredging in and around
the alignment further reduced the
blocking effect.
Dredging and reclamation
The dredging and reclamation contract
included the initial construction works
for the fixed link which began in August
1995. Over four years a total of 7.5
million cubic metres of (mainly) seabed
material was dredged, two thirds in
Danish waters and one third in Swedish
waters. The seabed consists of gravel
and stone, clay till and limestone with
flint layers.
Dredging was carried out by a
number of dredgers, traditional bucket
dredgers as well as a specialised
cutter/suction dredger for the tunnel
trench.
The objective was for the
completed link to have no net effect
on the water flow and on the
movement of salt and dissolved
oxygen through Øresund to the Baltic
Sea. Consequently the size and shape
of the peninsula and the island were
optimised to reduce the blocking of
the water flow through Øresund.
Further reduction to zero blocking was
achieved by compensation dredging.
All dredged seabed material was
reused in the reclaimed areas which
cut sediment spill to a minimum and,
in addition, reduced the need for
dumping sites as well as for import of
sand and gravel.
The dredging works included:
● Work harbours and access channels
at the artificial island and the artificial
peninsula
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