In 1953 the Netherlands were subject to terrible floods. As a country located on the Rihne delta, with a large portion of its land under the sea level, the risk of flood is always high, but at that time a sizeable storm over the Northern Sea, touching also Britain, Belgium and Germany, made the sea level rise over 4 meters as related to its usual level. As this happened by night, many people were caught while sleeping, and there were over 1.800 deaths.
A coastal protection plan was implemented, creating one of the most abstract and impressing contemporary landscapes, with a figure as target: 4.000 years, the period in which, as a statistical average, there would be a flood large enough to overcome that barrier with the same effects as the 1953 flood (in Spain, for instance, a lot is deemed subject to flood risk if that time is 500 years). The giant cost of the works and their maintenance has been compensated, at least partially, by a Dutch- specific know-how that is exported. I have visited the Netherlands, but never this area; the upper image (taken from http://www.holland.com) shows an entireley abstract and artificial landscape, in which every element has a logic.
The original calculations for the Delta Plan have been altered by the climate change forecasts and the knowledge derived from the 2005 Katrina disaster in New Orleans. The Netherlands are reexamining their flood protection policy, wich is the same as saying they have to rethink half their country.
metrhispanic 
Very interesting subject! An image can cheat however. What you see is a highly sofisticated framework that safeguards the sensitive balance of a protected national park landscape. The balance of this sea eco system could only be garantueed if the permanent tidle movements were maintained. So a dinamic, moving shutters dam was designed and put in place, in stead of a much easier to execute fixed earth and stone dam….So the essence of the compensation for the cost is dual and intricate; the combination of maximum protection against and manipulation of the sea and at the same time maximum freedom of this natural element to keep changing tide by tide the landscape and feeding a delicate ecosystem.