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<International Source Book On Environmentally Sound Technologies for Wastewater and Stormwater Management> 6. Europe (West) 6.0 Introduction 6.0.1 The countries of Western Europe The overriding reasons for the division of Europe into East and West were the availability of information and the routes to access it, the current situation and practices, the standards to be met, and the immediate priorities for action. Western Europe includes all State Members of the European Union plus five non-Member countries, viz.: Cyprus, Liechtenstein, Malta, Norway, and Switzerland. The State-Members of the Union make up the bulk of Western Europe. They had a population of 372 million in 1995. With the other 5 countries, the total estimated population by the year 2002 will be about 395 million. Taking the European Union alone, population density in 1995 was 115 inhabitants/km˛. There were almost 150 million households, and more than 15 million foreign residents. The Gross Domestic Product (GDP) was 6192 bn ECU in 1994. Some 55% of the population is actively employed, of which 5.5% in agriculture, forestry and fishing; 30.6% in industry, and 63.9% in services. As an average, there are 2.54 person per household, and in 1994, there were more than 150 million automobiles or more than 420 per 1000 inhabitants, more than 45000 km motor ways, and a rail network of more than 150000 km. 6.0.2 The situation at a glance The region is rich in important river systems some of which are very large. On the Continent, the rivers are often long and fed by many tributaries. Large cities and industries are often located upstream. The most outstanding examples are the Rhine, the Danube, Elbe, and Oder in Germany, the Warta and Vistula in Poland, the Rhone, Garonne, Loire and Seine in France, the Ebro, Duero, the Guadiana and the Taco in Spain, and the Meuse in Belgium and the Netherlands. Several of these rivers cross one or more international borders and call for concerted international action, e.g. the Rhine, Danube, and the Meuse. The water pollution and the consequent effects on water uses downstream are high in most cases. River systems in England, Italy Norway and Sweden and Finland are comparatively short. The major polluters are often located near their mouth or close to the sea, or on estuaries. Yet, in England and Italy, large polluters are also located in-land. There are only two sizable lakes in the region, the Lake of Constance and the lake of Geneva. They both receive Alpine water, are about 350 m deep and have moderate flowthrough rates. Both receive a fair load of domestic sewage but limited industrial wastes. The lakes have several riparian states; international coordination for the management of wastewater and stormwater exists. The smaller lakes in Switzerland, Germany and France and most of the other countries are of local and/or sub-regional importance. All pose problems of pollution both domestic and industrial. Groundwater is considered a special case in Europe. More than in some other regions of the world, groundwater is an important source for public, industrial and agricultural water supply and its protection against pollution is of paramount importance. The high density of population and industry in some of the countries poses important threats to groundwater quality. Water pollution became a public and political priority in the 1950s and 60s in all of the European countries soon after the reconstruction following World War II was aggressively initiated. The authorities concerned and the operating agencies maintain records and statistical information to the best of their capabilities. Initially, the information was not complete and not of a high reliability, often spotty and not comparable between countries. Nevertheless, the data demonstrated that many people were still not connected to sewerage and that the discharge of the sewage to rivers or lakes was generally unsatisfactory. Perhaps one third of the sewage collected in communal systems was discharged without any treatment. Of the remainder, perhaps half was treated by sedimentation and the rest by biological methods, often trickling filters. Activated sludge treatment was the exception rather than the rule. The Commission of the European Communities and the former Committee of Mutual Assistance in Eastern Europe promoted improved monitoring and recording of information. But full European cooperation in wastewater management was not possible until the late 1980s. Since then, surveys concerning wastewater management and water pollution control were undertaken as part of comprehensive studies of the European environment, i.e.:
From the above review it will be understood that Europe-wide information on wastewater management is gradually becoming "harder" though the information is still variable and incomplete, and in some cases confusing. The Second Assessment referred to above contains information of considerable interest: it shows that the percentage of the population served by wastewater treatment varies from about 50% in the Southern to about 80% in the Northern and Western countries. It concludes that wastewater treatment has improved in many countries during the past 10 to 15 years, especially in the South of Europe where the backlog was large. A larger proportion of the population has been connected to treatment plants and the treatment level has changed. There has been a pronounced change from primary to secondary treatment and with it, a substantial reduction of the organic degradation of European rivers. Moreover, in Western and Northern Europe, the introduction of tertiary treatment, usually with phosphorous removal, has grown substantially in the past decade. It is also observed in the Second Assessment that in the majority of the European cities, wastewater is still collected together with rainwater and discharged to water bodies and, accordingly, that eutrophication resulting therefrom is particular severe in urban estuaries where the input form cities is large. For instance, the Baltic Sea receives the effluents of more than 70 million people and from their industrial and commercial activities, and is showing increasing signs of stress. 6.0.3 Lessons of the past Western Europe of the Nineteenth Century was the cradle of todays technology and organizational approach for the management of waste water and stormwater, while, of course, many much earlier examples of sewerage, and stormwater disposal have been recorded as part of the history of the great ancient cultures and city states of the Far and the Middle East and the Mediterranean. Yet, in the case of Europe, it was the combined effect of urbanization, industrialization and enlightened local and central governments which not only called for action but also enabled the planning and implementation of projects of hitherto unknown magnitudes in the terms of the size of the population served, public health purpose, water pollution control and environment protection. Area-wide drainage systems were introduced in England during the second half of the Nineteenth Century. They became indispensable following the rapidly increasing use of the water flush toilette. They relieved the city of its stormwater and sewage without the nuisances created by the discharge of foul water in open street drains. But they polluted the River Thames and many others of the English rivers. The emerging industries were often built on the shore of the rivers and added their own share to water pollution. British engineers were called to replicate drainage systems in Continental Europe, e.g. Paris, Hamburg, Vienna, and many others. Soon, water pollution became a problem with a European dimension. In 1858, the Local Government Act prohibited the cities and towns in England to pollute rivers whenever other uses were thus impeded. Only 3 years later, in 1861, the Act was amended to the effect that sewage must be purified if otherwise the quality of rivers was degraded. River Pollution Commissions were established beginning 1868 and 1875. The Rivers Pollution Prevention Act became law. The lesson of these developments in England, the first country to undergo rapid industrialization, stipulates that without a political will and legislation, water pollution from sewage and stormwater cannot be prevented - even today. Three other lessons emerged from the English experience:
As regards the technology for the purification of sewage and industrial effluents, the English experience is also noteworthy. Soon is was recognized that land disposal of untreated waste water was not to be recommended. The putrescence of the organic matter in sewage and industrial waste was better understood as well as its effects on lagooning and sedimentation. Research with filtration soon pointed to intermittency and than to biological treatment. Efforts were made to study chemical methods for coagulation. Among the most important developments was the research to measure and estimate the pollution load originating from a population, its composition and its environmental effects. Today, this sounds trivial. But before the turn of the Century, and for some time thereafter, this type of information was lacking, and the construction of sewage treatment plants were subject to many uncertainties. The first steps towards today´s sewage treatment technologies involved the invention of methods, and often machinery, for the removal of grit and settleable solids. Only thereafter, was the digestion and the drying of sewage sludge given the same degree of attention. Many designs were tried, often on a large technical stage. Some of the designs involved structures combining sedimentation in an upper chamber and the anaerobic digestion in a lower chamber. A breakthrough was the invention of the Imhoff tank by Karl Imhoff in 1906, a design adopted throughout the World . Next on the agenda were filtration, bio-filtration and trickling filters. Chemical coagulation was tried but generally not found satisfactory at the time. In 1914, Lockhett invented the activated sludge process. During the last 150 years, many things have changed, i.e. the problems, the scientific base, public perception and priorities, the amount money and other resources available for the proper management of waste water and stormwater, the availability of trained personnel, and technology itself and its cost. There are many other lesson to be learnt from the European experience with respect to the gradual extension of wastewater and stormwater systems from the bigger cities and towns to the smaller communities; the evolution of the environmental standards to be met, especially now that much progress has been made in the reduction of the organic load discharged into rivers after biological treatment of the wastewater; the reconstruction after World War II; the handling of industrial wastes; the best ways of reducing stormwater overflows; the effectiveness and efficiency of treatment technology; standardization; surveillance; and, ultimately, operation and maintenance and the training of the many personnel needed for the planning, implementation and operation of wastewater and stormwater systems. A unique lesson offered by Western Europe relates to wastewater management in the context of the integration of Europe and the role of the European Union (EU). While perhaps not of immediate and direct application to the developing countries, this lesson is nevertheless relevant in many ways. It is therefore discussed in some detail throughout this Overview.
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