Ijsselmeer Basin
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euwareness netherlands Case Study 1: IJsselmeer Basin Dave Huitema Case Study 1: IJsselmeer Basin Dave Huitema April 2002 University of Twente (UT) Center for Clean Technology and Environmental Policy (CSTM) PO Box 217 7500 AE Enschede The Netherlands Tel: +31.53.489.3203 Fax: +31.53.489.4850 Website: www.utwente.nl/cstm Email: [email protected]; [email protected]; [email protected] EUWARENESS is a research project on European Water Regimes and the Notion of a Sustainable Status. Research institutes from six European countries (Netherlands, Belgium, France, Spain, Italy, Switzerland) have been cooperating in this two year project (2000-2002). More information is available on www.euwareness.nl. The project is supported by the European Commission under the 5th Framework Programme, and co-ordinated by the University of Twente in the Netherlands. Nurturing nature: how to make a lake and maintain it The IJsselmeer case as an example of some modern dilemma's and tendencies in Dutch water management. 1 Zuiderzee and IJsselmeer Introduction This case study is on one of the larger fresh water lakes of Europe, named the IJsselmeer. The IJsselmeer is located in the heart of the Netherlands (see map below) and covers about 2,000 square kilometers, surrounded with about 600 kilometers of shore. Figure 1: The IJsselmeer-area. The color differences in the map indicate depth of the lake. At the deepest parts, this is 7 meters below NAP. The surrounding provinces are Noord-Holland, Friesland and Flevoland. The history of the IJsselmeer is a colored one. In the Roman age, the lake was much smaller and a freshwater lake. But rising seal levels, declining land, and a recurring river that feeds the lake (the IJssel) caused an enormous change. It became much larger (3,700 square kilometers) and became saline too. An inland sea, called the Zuiderzee was born. This sea was extremely dangerous for the hinterland (floods in 1287, 1570, 1573, 1686, 1825, 1875, 1916) but measures to enhance safety were difficult to devise because of political resistance or lack of technical means to control such a large water mass. When referring to political resistance, one can think of the importance of the lake for shipping purposes, which has implied that the city of Amsterdam used to block attempts to shorten the shore line. Technical capabilities for damming and poldering large water bodies were only developed in the course of the 19th century. It is in this century that the first plans were developed for the poldering (turning into land) of the Zuiderzee. The plans were largely deemed unrealistic and unnecessary, but this slowly started changing. In 1886, the Zuiderzee Vereniging (Zuiderzee Association) was founded, with the purpose of gaining government approval for a plan to conquer the Zuiderzee. This group commissioned a relatively unknown engineer, Mr. Lely, who the thought out what seemed to be a relatively realistic approach for the creation of a new polder. The plan was presented in 1891 and apparently impressed many. A state committee of experts was appointed which had to study the whether separating the Zuiderzee from the North Sea and creating polders would be in the national interest. In 1894, the Committee advised the government that that was the case indeed. De Pater (2000) emphasizes how the proponents of the project had to work the public opinion to achieve this result and drew upon images that proved long living. The Zuiderzeevereniging portrayed the Zuiderzee as nothing but a 'dead' piece of water that had not been put to beneficial use yet. Besides, the sea was an 'internal enemy' that should be conquered as it could strike at unexpected times. The Zuiderzeevereniging sought to connect the project to the certain level of nationalism and the desire for nation building that was present at the time (a grand project would should foreigners that the Netherlands was a modern country). One might wonder why the plans then were not implemented. Opposition from active users of the lake was not as great as it had been in the past. The Zuiderzee had become far less relevant as a shipping water as ships from Amsterdam could sail to the North Sea over two new canals. The only active users of the sea were fishermen, who naturally objected to the polder plans. This opposition was not formidable and the proponents of poldering effectively portrayed the fishery communities as a marginal affair. More substantial opposition came from important departments as the Ministries of War (which saw the Zuiderzee as part of the Dutch defense system) and Finance (which feared the costs of the project). Consequently, implementation was yet far away. Two events finally pushed Mr. Lely's faltering project into realization. First, the Netherlands suffered from a flood of the Zuiderzee in 1916 that caused considerable damage, very deep into the country. Secondly, the First World War eliminated some of the traditional trading relations. Thrust upon itself as a neutral country, the Netherlands found that food production in the country was not sufficient for self-maintenance and food shortages were experienced. As poldering the Zuiderzee was presented as a solution to the chronic problem of flood safety (the project would reduce the shoreline and tide) and a possibility for creating additional agricultural land, resolve to implement Lely's plans stiffened despite continued resistance from the fisheries sector. A special agency to implement the plan (National Agency for the Zuiderzee Works, in Dutch 'Rijksdienst voor de Zuiderzeewerken' (from here on ZZW)) was founded and this agency set to work, generally following Lely's approach, but with significant changes at opportune occasions. High points in the project were the realization of the 30 kilometer long 'Afsluitdijk' (closure dam) between the provinces of Friesland and Noord-Holland in 1932 and the subsequent creation of the new polders (about 1,700 square kilometers of new land). The dam sealed of the Zuiderzee from the North Sea and Wadden Sea, and coupled with the continued influx of river water, the sea turned into a freshwater lake. After realization of the dam, polder construction started. Figure 2 shows some of the ideas that have existed on the location of such polders. With our current knowledge, the top left figure seems rather unrealistic (compare with figure 1), but the others are not far from what was later realized. After construction, the polders were landscaped by a special branch of the Public Works Agency (Rijkswaterstaat), called the Rijksdienst voor de IJsselmeerpolders (from here on RIJP). Figure 2: Plans for the creation of polders in the IJsselmeer area The considerable length of the implementation period of the Zuiderzee-project (1918-1985 or so) allowed ZZW and RIJP to keep learning from previous experiences. Especially the initial omission of 'corner lakes', bodies of water that separated the new from the old land, caused problems in the old land. It was found that a new polder, lying below sea level, attracted great amounts of ground water from under the old land, thereby causing subsidization and drying up of land. The damage to existing uses (agriculture, buildings) was considerable and the newer polders were built with a so-called corner lake to prevent such damage. These corner lakes are clearly visible on map 1 and are part of the IJsselmeer basin. Another change that can be observed is the way the new polders were put to use. Not only were ever-changing techniques used to make the polder dry and to expulse the salt, the land use for which the polders were used changed as well. The first polders were about 90% agricultural land, but the final one that was created (Southern Flevopolder) was only for 50% devoted that purpose. The later polders were much more tailored for housing (18%) and natural area (25% for said polder). The current uses of the IJsselmeer Being such a large area, and being so close to large populations, it should be no surprise that the IJsselmeer has many functions, both from the perspective of the surrounding land and from a water system perspective. Drinking water preparation: need for achievement of strict water quality standards and clean up of polluted water soil. A summary of the functions that the lake fulfils, from the perspective of the various users, would go something like this: - Flood control: retention basin for high water levels in the IJssel (and Rhine) basin, control of influx of North Sea water at high tide, control of risks of flooding by the IJsselmeer itself. - Agriculture: reserve of fresh water in summer, drainage area for superfluous water in the winter, flushing out saline water under mainland, potential site of expanded agricultural acreage by creating polders, receptor of pollution (see industrial and urban development). - Nature: the IJsselmeer is part of the Ecological Main Structure (Ecologische Hoofdstructuur); large parts protected by the Habitat and Bird Directive (European Union) and Nature Protection Act (Netherlands). Main reasons: presence of protected bird and fish types and status as 'open landscape'. Presence of certain species requires achievement of certain water quality standards and clean up of polluted water soils. - Recreation and tourism: sailing, windsurfing, beaches, vacation resorts. - Military: practice area for the army (gun firing range) and air force (fly zone). - Industrial: use of cooling water, receptor of pollution discharges. The latter function was used intensively in the 1950s/1960s. Much pollution from the Rhine systems was absorbed by particulates that fell on the lake soil. The soil is locally of very poor quality. - Energy production: two power plants present that use cooling water. Plans for park to generate wind energy by windmills.