the Coordinating Committee Dike-raising' in
wh :h the Government and all interested
ore jnizations are represented. This procedure
ha; proved to be very useful. Two thirds of the
rai: ngs in accordance with the Delta-Act have
aire ady been executed. At present works
am runting to 700 million guilders still have to
be one. A multiple longrange plan has been
set jp in accordance- as much as possible-
wit the urgency of the various projects.
Dil -raising in Noord-Brabant
Sir e the flood disaster in February, 1953, the
coi rol of the sea defenses in the Province of
No rd-Brabant has been centralized in one
so ailed 'Hoogheemraadschap' (Water
Au tority). In the first instance the damage was
rep ired according to a so-called 'weak spots
pi; V. The safeguarding of the northern basin
by he Haringvlietdam made it possible to
inc rporate old schemes to make the Biesbos
an the Donge-area surge-free.
Ec ogical aspects of the partial dike-raising
ale g the Oosterschelde
Th partial raising of the dikes might prove to
be armful to the natural environment.
Exi cution in the wet in particular, requiring a
ter oorary working zone of 15 meters, might
ca e considerable damage especially to the
on rdike saltings and to a lesser degree to the
int "sections. The dikes proper when their
ole titched stone slope is preserved, will regain
an iteresting inter-tidal flora and fauna. On the
tur he new maintenance system will cause
the isappearance of a great part of the old flora.
Th Delta-flume
In c nnection with the preliminary studies for
the orm-surge barrier in the Oosterschelde,
so nechanical tests have been made on a
larc scale, among other things, in the
lat atories of Oregon State University.
Ho ver, in the Netherlands a need is being felt
too >r large model facilities for combined soil
me anical/hydraulic research. In the near
fut e a new flume will be installed in the
Hyc: ulics Laboratory in Delft with a total
len h of 250 meter and a cross-section of 5 x 5
m2.
Lat r provisions for the Oosterschelde works
The nstruction of a storm-surge barrier
across the mouth of the Oosterschelde will
represent work for 18 000 man/years. In view of
the shortage on the labour market in Zeeland,
particularly in the concrete sector, labour will
have to be supplied, mainly from
Noord-Brabant. For that reason the idea has
been considered of locating the construction pit
for the piers on the construction island near the
Philips-locks. In that case the navigation route
towards the mouth of the Oosterschelde would
have to go via the Zeeland-bridge. The
construction site will in fact be established in
the former 'dock Schaar' at the mouth of the
Oosterschelde. In order to shorten travelling
times a fixed bridge connecting the
construction site with the shore is to be
constructed.
Provisions for a road connection across the
storm-surge barrier
A decision will have to be taken about the
provisions which are to be made regarding the
piers so that at a later stage the construction of
a road connection across the storm-surge
barrier will be feasible. A prognosis has been
made about the expected through-traffic, the
local and recreational traffic. A double lane road
with a parallel road will amply meet the
estimated demand.
Progress with studies and preparations in
connection with the storm-surge barrier. The
second semester of 1977
The alterations that the design of the
storm-surge barrier underwent in the second
half of 1977 are mentioned here, insofar as they
are not discussed in separate articles.
Thus, the distance between the piers will be
enlarged to 45 meters. The idea to install double
gates in the dam orto leave the possibility open
to do so, at a later stage, has been abandoned
definitely. With the design of the auxiliary
material progress has been made too.
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