Operation of Complex Hydraulic Works. The Case of Delta Project in Netherlands

The present postgraduate diplomatic work titled "Operation of Complex Hydraulic Works. The Case of Delta Project in Netherlands" becomes in the frame of partial fulfillment of requirements in the Interdisciplinary-Interdepartmental Program of Postgraduate Studies "Environment and Development" of the National Technical University of Athens with coordinating school the School Of Rural And Surveying Engineering. It is acceptable from the world scientific community that the climatic change is a fact, with the phenomenon of greenhouse to constitute the most serious danger for the Earth. Powerful and violent meteorological events affect enough regions of planet resulting in loss of human lives and economic damages for the affected regions. Coastal regions are tried by devastating forces of nature without to be excluded other areas of Earth, owing to the combining act of rising of sea level and the happening of violent meteorological events due to the phenomenon of greenhouse which affects those that the elevations of the earth’s surface and topography allows to happen irreparable floods. Netherlands and more specifically the south-western delta that is formed by the rivers Rhine, Meuse and Scheldt-that constitutes also the region of study of present work-present the particular element that the majority of Netherland’s area it is laid under the level of sea. This leads in combination with the danger of storm surges and overflows of above rivers to the extremely dangerous mixture that can happen in the region. At the past Netherlands has experienced disastrous floods that originated either from the sea or from the overflow of rivers due to intense rainfalls with climax the flood in 1953 in which they were lost 2,000 human lives approximately. By that time moment it was decided to design and materialise one of the most complicated and complex worldwide hydraulic works of flood-preventing protection in the region of south-western delta. The total project included the manufacture of thirteen dams of permanent or mobile operation for the preventing of storm surges as well as the completion of an integrated system of management of water resources in Netherlands. The present work studies at great length these works presenting the method of manufacture and giving some elements of their operation. In the two initial chapters they are presented basic elements for the world climatic change, the phenomenon of greenhouse that constitutes the most serious component of climate change, the repercussions of this as well as the theory on the flood-preventing protection from the storm surges analyzing the mechanism of producing waves, the linear theory of undulations and the main influences that are connected with the waves and the shoreline change. Moreover theoretical elements are given for rainfalls and how these are quantified in order to design flood-preventing works. In the next chapter a rough description of country is mentioned initially and afterwards it is analyzed the coastline of Netherlands in the view of geological structure and the demographic distribution of residents that exist there since it constitutes the interaction area between land and sea. Moreover the intensely coastal transportation of sediments is analyzed that is mainly responsible for the formation of coasts in thousands years. In the fourth chapter they are mentioned the main floods that have happened in the past, while particular attention is given in the flood in 1953 presenting the climatic circumstances in that day that contributed to the loss of human lives. In the fifth chapter a detailed description of all works of the delta becomes up to today referring to the method of manufacture, functional elements and subjects that are related to environmental issues. In the sixth chapter an effort is attempted to be presented the operation of works in the delta region and as finally concluded during the development of this diplomatic work these works constitute only one of a lot of components of a national integrated system of management of water resources in Netherlands. In the seventh chapter environmental matters are presented that are related to the manufacture and operation of dams and the way the enclosure of the delta region influenced important environmental parameters before and afterwards the completion of works. Finally in the eighth chapter the main natural, social and economic changes are mentioned due to the climatic change that already takes place as well as how this will influence the management of water resources in Netherlands in future. The future scenarios of rise of the sea level make the hydraulic works in Netherlands essential for the maintenance of life, without however to be excluded other regions of planet in future that they present similar problems after the 70% of world population live in coastal regions. Consequently the experience that was acquired by the constructing of so extensive works is the foundation of knowledge and valuable experience of the way that can be dealt with similar situations. It is hoped that the present study will be helpful for the scientist and especially for the designing engineer of proportional hydraulic works.