Breakwaters

Breakwaters or seawalls are man-made structures built from granite and concrete, lining the coasts. Breakwaters were usually built to protect sandy beaches and reclaimed shores from strong waves and erosion. Such a habitat is rather similar to natural rocky habitats. But artificial environments like breakwaters, with steeply sloping or vertical seawalls, tend to have less biodiversity.

Many of Singapore's shorelines have been heavily modified. One can find breakwaters in places such as the East Coast Park, Changi Beach, West Coast, and the Southern Islands (including Semakau Landfill, St John's Island, and Sentosa Island).

                                                                    (A video on Breakwater in other countries) 

More Info About Breakwaters in Singapore . 

Coastal Protection:

BREAKWATERS

Location:

East Coast Park, Siloso Beach

http://www.geographicasia.com/coasts/ecp1.html:

Two new breakwaters have been built at Siloso beach, on the southwest shore of Sentosa island. They will serve to protect the beach there, as erosion has been accelerated by the wash from the high-speed ferries plying between the nearby World Trade Centre and the Riau islands of Indonesia. At almost a kilometre in length, Siloso beach is the longest of three artificial beaches built at a cost of $20 million in 1991. The new breakwaters cost more than $1 million. They are each eighty metres long and are placed about a hundred metres offshore.

Breakwaters are only needed at Siloso Beach and along the East Coast Park because elsewhere in

Singapore, longshore drift is negligible.

How:

The breakwaters may be small structures, made of granites and placed one to three hundred feet offshore in relatively shallow water, designed to protect a gently sloping beach

When oncoming waves hit these breakwaters, their erosive power is concentrated on these

structures some distance away from the coast. In this way, there is an area of slack water behind

the breakwaters, which thus will reduce erosion.

Limitations:

When the breakwaters deflect the incoming waves before they reach the shore, these

waves that are deflected to other places (exposed areas of the coast) causing erosion.

Breakwaters are unable to provide complete protection for the whole coast and therefore

unprotected areas will prone to erosion.

Check this out for the amzaing history about Breakwaters in Singapore ----> http://thelongnwindingroad.wordpress.com/tag/breakwater/