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As the construction of offshore breakwaters requires skilled labor and
heavier machineries and quite expensive compared to shore connected
structures ,it should be considered only after ascertaining its effect as an
effective
protection
through
detailed
investigations
before
implementation.
2-Seawalls :
A seawall is a structure constructed parallel to the coastline that shelters
the shore from wave action .It is both massive and expensive . Erection
of sea wall shall be considered only after carefully evaluating the socioeconomic parameters.eg : it is recommended to construct a seawall
when the adjoining shore is highly developed and the intensity of storm
atttack is severe.
3-Groins :
A groin is a shore connected structure constructed perpendicular to the
coastline and jetting into the sea which serve as barrier in trapping the
longshore sediment transport or control longshore currents . Different
plan shapes of groins have been employed for trapping the sediments in
the nearshore .
The major parameters that decide the effectiveness of a groin in a given
location are net and gross sediment transport rates , water depths at the
seaward tip of the groin , surf zone width , structural permeability and
grain size distribution of sediments.
4-jetties :
Jetties are usually constructed perpendicular to the shore ; it can be
effectively used inside harbor basins for transfer of cargo
5-Revetments :
Revetments are structures deployed primarily to improve the stability of
the sloping surfaces along the shore. It is a durable and environment
friendly erosion protection system for berms , slopes riverbanks and
shorelines .