276
R.H. Charlier and Chr. P. De Meyer
In the latter location beach nourishment over a distance of 5140 m (3,187 mi)
involving over 522,000 m 3 (685,000 cu.yd) of material is proposed to restore 9
1/2 ha (23 acres) of beach. The feasibility study points to the following impacts :
temporary disturbance of the benthos, increase in water turbidity, decline of
esthetic values, increase of automobile emissions and in noise levels. All are
however temporary.
In Japan 66 beaches have plans for artificial nourishment and 21 others have
already adopted this restoration method. Nourishment for sections of the
Egyptian coast is being considered 29b.
In Indonesia the severely threatened coast of south Bali is the subject of a
proposal for restoration, maintenance and protection of its beaches. Erosion there
results from wave attack, airport and hotel construction, and coral removal.
While existing protective structures are to be rehabilitated and integrated in the
new scheme, the project combines traditional "hard" structures with extensive
beach nourishment.
3.4
Beach Dewatering and "Plates" Systems
In Chapter I, the matter of water absorption by the beach was brought forth in
connection with erosion. Dewatering has been proposed as an anti-erosion
method. Adams (J.W., 1989, The fourth alternative - Beach stabilization by
beachfore dewatering : Coast. Zone '89 III, 3958 - 3973) predicts savings
ranging from 25 to 50% depending upon original renourishment life and cost.
The method allows to prolong the useful life of a renourished beach, by
decreasing the erosion rate, in some instances to extend it indeficultely by
stabilizing the beach. Dewatering is, however, not a substitute to hard or soft
beach protection, rather it is supplementary. It can, nevertheless, be sometimes
applied as a self-sufficient system. The extra cost, however, can be rapidly
recuperated, and apparently, even economies realized because over a period of
four to five years renourishment expenses can be drastically cut.
The idea, and some systems, have been tested, with excellent results in Denmark
(Totsminde, Firsthals beach) and in Florida (Sailfish Point). In The Netherlands
polders drainage canals are a de facto implementation of the underlying
principle, and in South Africa well points were used ; the diamond exploitation
company, Consolidated Diamond Mines (R.H. Charlier, 1991, Marine
aggregates, Prognosis, Environmental Conservation, extended a beach seaward
using the dewatering approach.
R.H. Charlier and Chr. P. De Meyer
In the latter location beach nourishment over a distance of 5140 m (3,187 mi)
involving over 522,000 m 3 (685,000 cu.yd) of material is proposed to restore 9
1/2 ha (23 acres) of beach. The feasibility study points to the following impacts :
temporary disturbance of the benthos, increase in water turbidity, decline of
esthetic values, increase of automobile emissions and in noise levels. All are
however temporary.
In Japan 66 beaches have plans for artificial nourishment and 21 others have
already adopted this restoration method. Nourishment for sections of the
Egyptian coast is being considered 29b.
In Indonesia the severely threatened coast of south Bali is the subject of a
proposal for restoration, maintenance and protection of its beaches. Erosion there
results from wave attack, airport and hotel construction, and coral removal.
While existing protective structures are to be rehabilitated and integrated in the
new scheme, the project combines traditional "hard" structures with extensive
beach nourishment.
3.4
Beach Dewatering and "Plates" Systems
In Chapter I, the matter of water absorption by the beach was brought forth in
connection with erosion. Dewatering has been proposed as an anti-erosion
method. Adams (J.W., 1989, The fourth alternative - Beach stabilization by
beachfore dewatering : Coast. Zone '89 III, 3958 - 3973) predicts savings
ranging from 25 to 50% depending upon original renourishment life and cost.
The method allows to prolong the useful life of a renourished beach, by
decreasing the erosion rate, in some instances to extend it indeficultely by
stabilizing the beach. Dewatering is, however, not a substitute to hard or soft
beach protection, rather it is supplementary. It can, nevertheless, be sometimes
applied as a self-sufficient system. The extra cost, however, can be rapidly
recuperated, and apparently, even economies realized because over a period of
four to five years renourishment expenses can be drastically cut.
The idea, and some systems, have been tested, with excellent results in Denmark
(Totsminde, Firsthals beach) and in Florida (Sailfish Point). In The Netherlands
polders drainage canals are a de facto implementation of the underlying
principle, and in South Africa well points were used ; the diamond exploitation
company, Consolidated Diamond Mines (R.H. Charlier, 1991, Marine
aggregates, Prognosis, Environmental Conservation, extended a beach seaward
using the dewatering approach.