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Case study 8.2 Shoreline changes near Wexford Harbour, Ireland
Wexford harbour in south-east Ireland (Case Fig. 8.2a) is a large estuary partly separated from
the Irish Sea by a sand and gravel barrier. Associated with its wide inlet are extensive flood
and ebb-tidal deltas. Locally generated south-easterly storm waves and diffracted ocean waves
produce a northerly drift. The beach in the south of the bay is backed by cliffs of glacial till.
A resistant bedrock headland (Greenore Point) in the south provides a hinge for development
of a crenulate bay that extends northwards and forms Rosslare Bay. At its maximum extent,
the spit that forms the northern part of this shoreline was 8.3 km long but lost about 3 km of its
length between 1925 and 1983 (Case Fig. 8.2b) as the spit was breached and eroded by storm-
generated waves. Erosion of the spit was viewed with concern by the local authority because of
the tourism associated with the beach, which was considered the only safe bathing area in the
region. A variety of small-scale coastal protection structures were emplaced (Case Fig. 8.2c).
Groynes were emplaced to reduce longshore drift and rock armour was constructed adjacent to
the spit terminus in 1965 - 66. The apparent interruption of longshore drift by a pier at Rosslare
Harbour (constructed in 1882 and extended by 1902) was perceived as the reason for the
erosion. A sandy beach built up to the south of the harbour. In 1978 the harbour was replaced
by an impermeable breakwater and seawall.
Subsequent research (Orford 1988) suggests, however, that the shoreline erosion was re-
lated to the realignment and failure of the spit rather than interruption of the longshore drift.
Realignment of the coastal planform that included the mainland beach and the spit, by a
(b)
(a)
1925
Wexford
Harbour
Irish
Sea
The
Raven
Point
Study
area
1957
Wexford
Harbour
Wexford
+
Breach
Rosslare
Spit
1950
N
Rosslare
Bay
+
Rosslare Strand
?
N
0
5 km
+
Rosslare Harbour
Greenore Point
Breach 1965-66
Rock /tetrapod breakwater
(1967)
1983
Stone groyne
1.0 km
0
0.5
Rosslare
Spit
Carnsore
Point
Wooden groynes (1965)
Case Fig. 8.2 (a) Coastal setting of south-east Ireland showing Wexford Harbour, Rosslare Bay. (b) History of spit
disintegration: H.W., high water. (After Orford 1988.)
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