system in all its aspects it has been possible to
track down the weakest links, and to strive for
the relevant improvement. For operational
purposes the forecasts being made at present
are sufficiently trustworthy.
The Bergse-Diepsluis
Originally there was a plan to build a so-called
'lift lock' in the Oesterdam in front of Bergen
op Zoom, with a chamber measuring 90 m x
10 m. However on reconsideration it was
decided to make a lock of 34 m x 6,5 m,
without measures to combat the salt/fresh
water load. The sill will lie at M.S.L. -2,50 m at
the Zoommeer side, and at M.S.L. -4m on the
Oosterschelde side. A number of yachts and
fishing boats will obtain mooring on the
Oosterschelde side of the lock so that daily
locking wil not be necessary.
A bascule bridge will be built across the lock.
Operation of the lock will be done from an
operating building on the south side, and there
will possibly be a system for automatic (self)
operation. The locking time will last about 35
minutes.
The lock should be completed by the end of
1986: then work wil commence for the closure
of the Tholense Gat.
The future arrangements of the Schelphoek
area
There is an inner lake on the south coast of
Schouwen-Duiveland which was formed at the
flooding of 1953. This area known as the
Schelphoek has served as a work harbour and
work terrain during the execution of the Delta
Works. Now that this purpose has almost been
served a report has been set up on possible
future use. The functions under consideration
lie in the field of nature management, fishery
and recreation.
Five clearly differing alternatives have been
proposed, which have all been tested against
the Oosterschelde policy plan whithin which
they have to function. The alternatives involving
large extension of recreative facilities do not
comply in this respect.
Nature cultivation possibilities on sea dikes
A salt-prone type of vegetation is possible on
the lower parts of the outer slope of the sea
dikes. However since these outer slopes are
being increasingly covered in concrete blocks
the area for this type of vegetation is fast
decreasing.
An inventory held in 1982 showed 100 species
of plants, of which 23 were salt-prone. Their
survival on these frequently water drenched
stone slopes is determined mainly by the gaps
between the stones and by the earth filling. In
order to improve these chances the form of the
slope could be adjusted, the stone slope could
end earlier or else new stone types could be
applied.
This article provides a number of suggestions
whose value will have to be tested through
further research.
The Wieringer sea dikes
Sixty years ago the Wieringer sea dikes were
adapted to the new tide regime which occurred
as a result of the Zuiderzee works. After the
storm flood of 1953 the design levels for these
dikes were once more raised, to a level of
M.S.L. +8,50 m so that statistically they would
be exceded only once in 4000 years. With extra
allowance for settlement the top rose to
9-9,50 m.
Since 1978 the construction has been worked
on annually in the period April-October. The
new sea dike, usually on the sea side of the old
one, is pumped with sand from the Waddenze(
The very last part of this reinforcement of the
dike features in the planning for 1989.
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