breakwaters (-): they are costly to build due to the materials needed and the manpower needed, are unsightly, and protect the coast eventually, causing zones away from breakwaters to be vulnerable to wave action and erosion. For eg, in netherlands, breakwaters are estimated to cost about EUR 10000 to 50000 per running metre. In portland harbour, england, breakwaters caused erosion and flooding problems, destroyed properties, beaches and communication infrastructure.