The Integrated Rhine Programme Flood Control and Restoration of Former Floodplains Along the Upper Rhine
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The Integrated Rhine Programme Flood control and restoration of former floodplains along the Upper Rhine UMWELTMINISTERIUM CONTENTS Preface . 3 The risk . 4-5 The River Rhine – a wild river falling prey to human interference 6-7 The Integrated Rhine Programme (IRP) . 8-9 The possibilities and impact of flood retention on the Upper Rhine . 10 The Upper Rhine retention areas down to Mannheim . 11 Flood protection in harmony with nature . 12-13 Using the Altenheim Polders in the event of flooding . .14-15 New refuge for a large variety of fauna and flora . 16-17 Outlook . 18-19 Imprint Editor: State Ministry of the Environment Baden-Württemberg Postfach 10 34 39 in 70029 Stuttgart, Germany available from: Regierungspräsidium Freiburg (Regional Administrative Authority Freiburg) 79083 Freiburg i. Br., Germany Editorial staff: Astrid Griesbaum, Wolfgang Migenda, Dr. Ulrike Pfarr, Elke Rosport Graphic design: Maerzke Grafik Design, Leonberg Translated by Ilona Kronenberg, Solingen Photo credits: Hans Bertram, Munich p. 5; Brugger aerial photo, Stuttgart pp. 8/9; Dannen- mayer, BNL Karlsruhe pp. 1, 12 and pp. 14/15; Dr. Homagk, LfU Karlsruhe p. 16; Steinmetz LfU Karlsruhe p. 13; Maerzke pp. 1, 2, 6, 8, 10, 12/13, 15, 16, 17, and 18/19; Staeber pp. 12, 13, 14 and 15; Richter, Freiburg pp. 4, 10 and 13; all other photographs taken by Regierungspräsidium Freiburg printed on non-chlorine bleached paper 2nd Revised edition All rights reserved; reproduction in part or in whole without prior permission of the editor is prohibited. Stuttgart, August 2007 Floodings concern every single one of us! Again and again, flood events like those experienced in Baden-Württem- berg in December 1993 as well as in April and June 1994 result in catastrophic inundations. During the flooding that occurred in May 1999, the Upper Rhine area was only spared the worst due to the fact that the existing flood retention facilities were used. Moreover, we should also recall the devastating floods along the River Oder back in July 1997 and those along the River Elbe in August 2002. Time and again, these flood disasters clearly emphasise one thing: Floodings concern every single one of us. They destroy livelihoods, property and, if the worst comes to the worst, even claim human lives. Due to climate change, we need to brace ourselves for more frequent heavy downpours in the future, a development which will lead to mounting flood hazards. This gives more significance to comprehensive flood control. We cannot prevent flooding, as it is a natural phenomenon. Nonetheless, knowing about the risks enables us to take the necessary decisions to minimise or at the very least alleviate the ensuing damage by means of bespoke flood protection measures. In this respect, the Integrated Rhine Programme can make a substantial contribution. It provides the right concept for flood control and the restoration of former floodplains along the Upper Rhine. On several occasions, the existing facilities have demonstrated their impact and effi- ciency in terms of flood protection. The Altenheim Polders have already witnessed the re-development of floodplain communities. Now it is imperative to swiftly continue implementing the Integrated Rhine Programme within the next years. To achieve this objective, all of us have to join forces. The federal state, the Federal Government, the municipalities and the population are required to take action. For this purpose, we need a broad consensus among society and politics which is to be promoted by means of this brochure. Tanja Gönner Minister of the Environment of the Federal State of Baden-Württemberg 4 Flood hazard The risk In its present state, the River Rhi- ne only has a limited conveyancing capacity for floodwater downstre- am of Iffezheim along the barrage- regulated stretch of the River. Thus, the conurbations of Karlsru- he, Mannheim/Ludwigshafen and Worms must brace themselves for considerable damage caused by flooding when the River overtops its embankments and inundates the areas behind the levees. The total damage resulting from a major flooding (1 in 200-year flood) in the Upper Rhine plain between Iffezheim and Bingen is estimated to amount to more than 6 billion euros. Moreover, it is expected that such an event will also result in human casualties. Foto: Sascha Kopp THE CAUSES Floods on the Upper Rhine pose a threat Until the 70s, prior to the construc- to 95 towns and tion of the dams on the Upper Rhine be- municipalities with a total population of tween Kembs and Iffezheim, the situation ® 700,000 Altrip (left) Mannheim (right) ® ca. 350,000 jobs proved to be less dramatic. At that time, ® covering a surface the number of natural floodplains along conveyance along the northern stretch of that can no longer run off between the area of ca. 1,000 km2 the southern section of the Upper Rhine the Upper Rhine to an acceptable level. local main dams of the Rhine along was still sufficient, allowing the retention With the construction of the dams, the the northern stretch of the Upper Rhine of water while reducing the river flood floodplains were cut off from the natural downstream of Iffezheim. discharge regime of the Rhine. Today, flooding events involving comparable flood volumes generate larger river discharges Flood hazard 5 THE SOLUTION THE PLAN IS FULLY WORKING OUT be reversed. Housing estates and industrial As illustrated by the example of the According to current estimates, the areas are still being built on potential River Rhine, it was not so long ago that costs incurred in connection with the Inte- floodplains. As a consequence, the flood people were trying to protect the wetlands grated Rhine Programme total around 775 hazard will not recede, but increase. Flood taken away from the rivers by means of million euros; in contrast, the anticipated protection can never be absolute. People dams which were rising higher and higher. losses exceed an amount of 6 billion euros living in the immediate proximity of the Today we know that this tremendously plus the potential loss of human life. Sub- river must always be prepared for the Taking stock of exacerbates the flood hazards for down- sequent to the completion of all flood re- worst. A reduction in unavoidable losses floodlosses: stream areas. For this reason, raising the tention facilities on the Upper Rhine, the also forms part of efficient flood control. The economic damage caused by a major dams along the vulnerable section of the measures embraced by the Integrated The respective precautions as well as reli- flood event on the Upper Rhine totals Upper Rhine beyond their current height Rhine Programme will prevent almost all able flood forecasting and warning systems approx. 6 billion euros. must be ruled out in terms of a potential of the above-mentioned losses, even in the effectively help lower the losses, even dur- The measures taken within the framework solution to the problem. Thus, the only event of a 1 in 200-year flood. So this is a ing major flood events. of the Integrated Rhine Programme help feasible solution to attenuate critical flood really worthwhile investment! reduce these losses. peaks embraces the creation of flood- Besides, things will also work out for plains. On the Upper Rhine, there is still a nature. There will be a rise in the small possibility of doing so in quite a number number of remaining natural floodplains of areas. In former times, prior to the con- that constitute the original habitats of a struction of the dams, these areas were al- rich diversity of fauna and flora which ways subject to inundation; today, they are used to be typical of the upper Rhine mainly used for forestry purposes, with a plain in former times. In addition, this will small proportion set aside as farmland. also be beneficial to humankind. In many Many of these areas still bear witness to locations, man’s living environment will the past, as they embrace remainders of become more natural and attractive. the typical floodplain landscape which ex- isted along the Upper Rhine. PREVENTION IS BETTER THAN Reclaiming these areas for flood con- CURE trol purposes and developing semi-natural The flood retention measures carried floodplains is the objective pursued by the out on the Upper Rhine merely constitute Integrated Rhine Programme (IRP), the repair work and will by no means suffice Baden-Württemberg concept of flood con- as stand-alone measures. Human interven- trol and restoration of former floodplains tions undertaken along the river have to along the Upper Rhine. Housing estates, industrial zones and farmland are threatened by flooding. 6 History The River Rhine – a wild river falling prey to human interference Prior to the 19th century, the River Rhine was still a wild river by and large untouched by man. Subse- quent human intervention strongly View of the Upper Rhine altered the stream and resulted in furcation zone from the Isteiner Klotz a loss of floodplains. This increased date the terrain without coming across A navigable river down to the exposure to flood hazards. any major obstacles. However, the people Basle – all year round By implementing these measures Tulla THE WILD RIVER RHINE settling in the plains along the River Rhine created settlement areas and converted the – A NATURAL RIVER UNTIL THE perceived this scenario as a threat. Every marshy Upper Rhine plain into an area 19TH CENTURY now and then, permanently recurring suitable for farming and forestry purposes. About 200 years ago, the Rhine still floods engulfed whole estates, inundating Thus, people living in the immediate prox- used to be a wild river. In the section the vital fields for weeks in a row. The al- imity of the Rhine enjoyed a higher level located between Basle and Lauterburg luvial floodplains with their great diversity of protection against floods.