Lower Rh One Valley And Lake Bresse example essay topic

The Rivers of France The Rh^one system The Rh^one is the great river of the southeast. Rising in the Alps, it passes through Lake Geneva (French: Lac L'eman) to enter France, which has 324 miles of its total length of 505 miles. At Lyon it receives its major tributary, the Sa^one. In eastern France the direction of the main rivers is predominantly north-south through the Alpine furrow. The regime of the Rh^one is complex. Near Lyon the Rh^one and its important Is " ere and Dr^ome tributaries, draining from the Alps, have a marked late spring-early summer peak caused by the melting of snow and ice.

While this peak is generally characteristic of the river as a whole, it is considerably modified by the contribution of the Sa^one, of the Durance, and of some tributaries in the Mediterranean south as a result of the fall-winter rainfall peak. Thus the powerful Rh^one has a remarkably ample flow in all seasons. The course of the river and the local water tables has been much modified by a series of dams to generate power and to permit navigation to Lyon. The Rh^one also supplies cooling water to a series of atomic power stations. West of the Rh^one, the Bas Rh^one-Languedoc canal, constructed after World War II to provide irrigation, has proved to be an essential element in the remarkable urban and industrial development of Languedoc. East of the Rh^one the Canal de Provence taps the unpolluted waters of a Rh^one tributary, the Durance, supplying Aix-en-Provence, Marseille, Toulon, and the coast of Provence with drinking water and providing impetus for urban expansion.

At its delta, beginning about 25 miles from the Mediterranean, the Rh^one and its channels deposit significant amounts of alluvium to form the Camargue region. The Rhine system The Rhine forms the eastern boundary of France for some 118 miles. In this section its course is dominated by the melting of snow and ice from Alpine headstream's, giving it a pronounced late spring-summer peak and often generally low water in autumn. The Ill, which joins the Rhine at Strasbourg, drains southern Alsace. The Rhine valley has been considerably modified by the construction on the French side of the lateral Grand Canal d'Alsace, for power generation and navigation. The eastern Paris Basin is drained by two tributaries, the Moselle, (partly canalized), and the Meuse; the former reaches the Rhine by way of Luxembourg and Germany, and the latter, as the Maas (Dutch), reaches the Rhine delta at the North Sea by way of Belgium and The Netherlands.

The Seine system The main river of the Paris Basin, the Seine, 485 miles (780 kilometres) in length, is joined upstream on the left bank by its tributary the Yonne, on the right bank south of Paris by the Marne, and north of the city by the Oise. While the Seine has a regular flow throughout the year, there may be flooding in the spring and, occasionally more severely, during the customary fall-winter peak of lowland rivers. Efforts have been made to reduce flooding on the Seine and its tributaries by the building of reservoirs. A number of islands dot the Seine along its meandering, generally westward course across the central Paris Basin and through the capital city itself. One of these, the ^Ile de la Cit'e, forms the very heart of the city of Paris. Eventually the river enters the English Channel at Le Havre.

The Loire system The Loire, the longest French river, flows for 632 miles and drains the widest area (44,400 square miles). It is an extremely irregular river, with an outflow eight times greater in December and January than in August and September. Rising in the Massif Central on Mount Gerber-de-Jon, it flows northward over impervious terrain, with many gorge like sections. Near Nevers it is joined by the Allier, another river of the massif.

Within the Paris Basin the Loire continues to flow northward, as if to join the Seine system, but then takes a wide bend to the west to enter the Atlantic past Nantes and Saint-Na zaire. The Loire is artificially joined to the Seine by several canals. The river's torrential flow, a hindrance to navigation, covers its floodplain with sand and gravel, which has commercial importance. The river is also a source of cooling water for a chain of atomic power stations near its course, which has led to controversial regulation projects. The Garonne system The Garonne, in the southwest, flows through the centre of the Aquitaine Basin. It is the shortest of the main French rivers, with a length of 357 miles, and it drains only 22,000 square miles.

Its outflow is irregular, with high waters in winter (due to the oceanic rainfall) and in spring, when the snow melts, but with meagre flows in summer and autumn. Its source is in the central Pyrenees in the Aran (French: Joyeuse) Valley in Spain, and its main tributaries, the Tarn, the Aveyron, the Lot, and the Dordogne, originate in the Massif Central. With the exception of the Gironde estuary, which is formed by the confluence of the Garonne and the Dordogne and is fully penetrated by the sea, the whole network is generally useless for navigation and is filled with powerful, rapid, and dangerous currents. The smaller rivers and the lakes North of the Artois ridge, a number of small rivers flow into the Escaut (Flemish and Dutch: Scheldt) to reach its North Sea estuary through Belgium.

The Somme rises in northwestern France and flows a short distance into the English Channel, and in the southwest the Charente, rising in the western Limousin plateau, and the A dour, rising in the central Pyrenees, flow into the Atlantic. The French hydrographic system also includes a number of natural lakes of different origin. There are the lakes in depressions carved out by glaciation at the western periphery of the Alps, such as the lakes of Annecy and Bourget, the latter being the largest natural lake entirely within France. Others occur on the surfaces of ancient massifs and include the lakes of the Vosges. Some lakes are caused by structural faults and are lodged in narrow valleys, as are the Jura lakes. There are also lakes of volcanic origin, such as those in the Massif Central (crater lakes and lakes pond ed behind lava flows), and regions scattered with lagoons or ponds, either created by coastal phenomena, as on the Landes (Atlantic) and Languedoc (Mediterranean) coasts, or caused by impervious terrain and poor local drainage, as in the Sologne plain.

Major artificial lakes include the Serre-Pon con reservoir, on the Durance River in the Alps, and the Sar rans and Bort-les-Orgies reservoirs, both in the Massif Central. Transportation (of All) Despite the presence of major rivers such as the Seine, Rhine, and inland waterways carry little freight. Although still used to transport goods such as construction materials and agricultural and oil products, their role has progressively declined in the face of cheaper and faster alternatives. Traffic has also been lost due to the reduced inland movement of heavy raw materials and fuel products and to an inefficiently organized industry with too many small-barge operators.

The uneven and disjointed pattern of the waterways further restricts use. Less than a third of the commercial waterway system is of European standard gauge; moreover, the principal river and canal systems remain unconnected for the passage of large barges, so that no truly national or international network exists. France is served by a large number of maritime ports, reflecting not only its extensive coastline but also its importance as a trading nation; some 60 percent of French foreign tonnage passes through its seaports. However, as in other Western countries, France's merchant fleet has steadily shrunk, due largely to the difficulty of competing with lower-cost carriers. Freight traffic, consisting mostly of imports, is concentrated in a limited number of ports, principally Marseille and Le Havre. This imbalance is partly explained by the still-sizable quantities of crude oil that are unloaded.

Passenger traffic is less important but is dominated by cross-channel movements that are heavily concentrated on the port of Calais. waterways & canals France's waterway network of nearly 5,000 miles is based primarily on its rivers, but many of the low-capacity canals are being raised to the 1,350-ton standard. A major development planned in the 1970's in cooperation with West Germany was the construction to this standard of the North Sea-Mediterranean waterway via the canalized Rh^one and Rhine rivers. With four existing locks built for the Grand Canal d'Alsace, a projected lateral canal between Huningue and Strasbourg, the project was modified in 1956, and the four remaining dams were to be built on the Rhine itself and bypassed with short canals including four locks, three with two chambers each. Canalization of the Rh^one started with the building of the Port of Edouard-Herriot downstream from Lyon, and work proceeded on 12 locks and dams. Two new ports, serving Valence and Mont " eli mar, were being constructed.

Improvements were also made on the Marne-Rhine waterway, which provides an important internal trade route connecting the Paris Basin with the industrial regions of Alsace-Lorraine. The improvements included major works on either side of the Vosges summit level, replacing 23 old locks. At R' a new lock with a lift of 321/2 feet bypasses six locks and a winding section of the old canal; on the other side of the summit a new canal section bypasses 17 locks, which formerly required 8 to 12 hours to navigate. On this section the inclined plane of Saint-Louis-Arzviller deals with a difference in level of 146 feet with a horizontal length of 422 feet. Two tanks each carry a 350-ton barge.

Their 32 wheels run on four rails, and two sets of 14 cables connect the tanks to the two concrete counterweights. Improvements have been made to routes connecting the Seine with the north and east. The Canal du Nord was completed in 1965, and a bottleneck was removed on the Oise Lateral Canal with the building of two locks to accommodate through convoys to Paris. The Main-Danube waterway connecting the Rhine with the Black Sea was completed in 1992 and provides a route for traffic between eastern and western Europe through Germany The Rhone River (Detailed) The Rh^one River is the largest in the country in terms of volume of discharge. With its tributaries, particularly the Sa^one, Is " ere, and Durance rivers, it drains the French Alpine region. Among the principal tributaries of the Seine River, which is the main artery of the national inland waterway system, are the Aube, Marne, Oise, and Yonne rivers.

Nearly all of the French streams, totaling more than 200, are commercially navigable for varying distances. France has only a few lakes. The Rh^one is a historic river of Switzerland and France and one of the most significant waterways of Europe. It is the only major river flowing directly to the Mediterranean Sea and is thoroughly Alpine in character. In this respect it differs markedly from its northern neighbor, the Rhine, which leaves all of its Alpine characteristics behind when it leaves Switzerland. The scenic and often wild course of the Rh^one, the characteristics of the water flowing in it, and the way it has been used by humans have all been shaped by the influences of the mountains, right down to the river mouth, where sediments marking the Rh^one's birth in an Alpine glacier are carried into the warmer waters of the Mediterranean.

The Rh^one is 505 miles (813 kilometres) long and has a drainage basin of some 37,750 square miles (97,775 square kilometers). The course of the river can be divided into three sectors lying, respectively, in the Alps, between the Alps and the Jura Mountains and through the latter, and fin ally in the topographical furrow of Alpine origin running from the city of Lyon to the sea. Physiography The Rh^one originates in the Swiss Alps, upstream from Lake Geneva. It comes into being at an altitude of about 6,000 feet (1,830 meters), emerging from the Rh^one Glacier, which descends the south flank of the Dammastock, a nearly 12,000-foot peak. The river then traverses the Gretsch Basin, from which it escapes through a gorge, and flows along the floor of the Goes Valley at an altitude between 4,000 and 4,600 feet. It next enters another gorge before reaching the plain of the Valais, which extends between the towns of Brig and Martigny, and descends in altitude 2,300 to 1,600 feet.

In crossing this high and rugged mountain area, the river makes successive use of two structural troughs. The first runs between the ancient crystalline rock massifs of the Aare and of the Gott hard; farther downstream the second runs between the arched rock mass of the Bernese Oberland and, on the south, the massive rock face of the Pennine Alps. From Brig onward, the landscape changes. During the last Ice Age a large glacier, fed by several small ones, plowed down the valley floor of the Valais, and, except for some harder rock obstacles found near the town of Sion, succeeded in widening and deepening the narrow valley floor.

As it did so, it held back both the upper Rh^one and those of its tributaries that come down from the Pennine Alps. When the ice sheets retreated, both the tributaries-the Visa, Navigenze, Borne, and France-and the Rh^one cut new, deep gorges to connect their lower courses to the new valley floor. These gorges have created considerable difficulty for modern transportation, necessitating a series of hairpin-bend road links. After Martigny, where the valley floor is wider, the youthful Rh^one thrusts northward at a right angle, cutting across the Alps through a transverse valley. At first, near the town of Saint-Maurice, this is no more than a small gorge, but it soon becomes wider and flatter. There, too, the river route has been assisted by structural factors, specifically by a dip in the crystalline rock massifs running from Mont Blanc to the Aare and by the discontinuity between the limestone masses of the Dents du Midi and of the Dent de Morales.

Across the mountain barrier the muddy waters of the Rh^one enter another wide plain surrounded by high mountains and then plunge into the clearer, stiller waters of Lake Geneva, forming an enlarging delta. The second sector of the Rh^one's course commences with Lake Geneva, large (224 square miles) and deep (1,000 feet) and lying between Switzerland and France in a basin hollowed out of the less resistant terrain by the former Rh^one Glacier. Upon leaving Lake Geneva, which has turned the course of the river to the southwest and decanted the sediment from its waters, the Rh^one very quickly regains in full the milky colour so characteristic of Alpine rivers. Just below the city of Geneva, it receives its powerful tributary the Arve, which rushes down from the glaciers of Mont Blanc. From its juncture with the Arve to the French city of Lyon, the Rh^one has to cross a difficult obstacle, the undulating series of ridges forming the Jura Mountains. It does this by cutting through deep longitudinal valleys called vs. aux and transverse valleys called causes, which were formed when the Jura Mountains were uplifted during the Alpine orogeny.

As a result, the river follows a complicated zigzag course. At the town of Belle garde the river is joined from the north by the Val serine and, swinging south, plunges into a deep gorge now submerged in the 14-mile-long G' Reservoir. In the wider sections of its course in this region, the Rh^one runs through glacier-excavated basins that its own deposits have barely filled, causing intermittent marshy areas. It is also joined by the Ain, from the north, and, on the left bank, by the Fier and Guiders. The river next widens, and the terrain becomes less hilly and, at Le Parc (some 95 miles above Lyon), becomes officially navigable, although the average depth is no more than three feet. At Lyon the Rh^one enters its third sector as it heads south toward the Mediterranean, which is characterized by the great north-south Alpine furrow that is also drained by its principal tributary, the Sa^one.

The latter lies in the basins that the Ice Age glaciers hollowed out between the Jura Mountains to the east and, farther west, the eastern edge of the Paris Basin and the uplands of the Massif Central. It forms an important commercial link to the industrialized regions of northern France. From the city of Lyon onward, the river occupies the trough lying between the Massif Central and the Alps, a channel up which the sea of the Tertiary period (66.4 to 1.6 million years ago) ascended covering the present Rh^one valley. A body of water, Lake Bresse, spread over the Sa^one basin. Into this lake drained a river-the present Rhine-which then flowed south through the valley and into the Sa^one basin; later tectonic movements caused the Rhine to reverse its flow, and the Doubs, a tributary of the Sa^one, now partly follows the former Rhine drainage pattern.

In the late Tertiary the gulf of the sea was uplifted to expose the lower Rh^one valley, and Lake Bresse drained out to the south through the Sa^one River. Though the Rh^one-Sa^one corridor is underlain by sediments laid down during the Tertiary period, much of its present surface is formed by debris deposited by valley glaciers that extended from the Alps during the Pleistocene epoch (1.6 million to 10,000 years ago). These sediments were instrumental in cutting deep channels through the edge of the crystalline Massif Central, as evidenced at Vienne and Tain. The valley consequently takes the form of a series of gorges and basins, the latter often having a series of terraces corresponding to variations in the levels of ice and of river. Although the tributaries-notably the Ard " ec he-rushing down into the Rh^one from the Massif Central are formidable when in flood, the great Alpine rivers, the Is " ere, and the Durance, joining the left bank, are most important in their effect on riverbed deposits and on the volume of water.

Below Mon dragon the Rh^one valley becomes wider, and what was once a marshy landscape open to flooding has been regulated by a series of dams and canals. The river's delta begins near Arles and extends about 25 miles to the sea. Twin channels of the river, the Grand and Petit Rh^one, enclose the Camargue region. This region, formed by alluvium, is continuously extending into the Mediterranean.

The finer materials are carried by onshore currents to form the barrier beaches of the coast and the sandbars closing off the 'E tang de Be rre. One part of the delta has been set aside for a nature reserve, thereby protecting the feeding and nesting grounds of flamingos, egrets, ibis, and other rare species. Since 1962 the left bank of Fos has been transformed into a vast industrial complex consisting of port facilities, refineries, oil-storage tanks, and steel mills. Hydrology The flow regime of the Rh^one owes its remarkable mean volume to the influence of the Alps. At Lyon the flow amounts to 22,600 cubic feet (640 cubic metre's) per second; there, the Sa^one alone contributes 14,100 cubic feet per second. The Is " ere adds another 12,400 cubic feet per second.

The melting of the Alpine snows gives the highest mean flows in May, while the Sa^one attains its maximum in January. The flood volumes of spring and autumn are formidable, reaching 460,000 cubic feet per second for the Rh^one at Beaucaire, just above the delta. Thus, the Rh^one has an abundant flow but maintains a strong gradient almost to its mouth. At Lyon, for example, its altitude is 560 feet at 205 miles from the sea. As the size of the delta region testifies, the river transports enormous amounts of alluvial deposits and is also powerful enough to cut through a variety of rock masses. As a result, the Rh^one of today is well adapted to the production of electricity and, though difficult to navigate in the past, is now an important waterway from the Mediterranean to Lyon.

The economy The Rh^one basin constitutes one of the great economic regions of Switzerland and of France, draining rich plains as well as an important part of the Alps. The utilization of the region by humans, however, has required a long historical struggle, which entered a decisive phase only in the second half of the 20th century. The economy of the Rh^one region consists of five major elements: agriculture, industry, energy, tourism, and transportation. Agriculture in the Rh^one valley largely covers the low areas, plains, and islands. In the canton of Valais, the Rh^one has been diked and narrowed, and the surrounding plain has been drained.

Comparable works have been carried out in France, notably on the Is " ere, at Combe de Savoie and Gr', and on the upper Durance. River waters are used extensively for irrigation. Forage crops and livestock raising coexist with vineyards, fruit orchards, and vegetable farming; the Camargue region is noted for its rice fields. Industries, both large and small, have been established throughout the region. Notable concentrations include the aluminum and chemical plants in Valais, the oil refineries at Lyon, and the refineries and steel mills at Fos. The production of hydroelectricity is evident throughout the length of the Rh^one and particularly so in its lower reaches, where a series of dam projects have harnessed more than half of the entire potential hydroelectric power of the river.

In France several nuclear generating stations utilize river waters for cooling purposes. The course of the Rh^one has long attracted tourists, and tourism has played an increasingly key role in the regional economy since the mid-20th century. The great variety of recreational activities offered-from skiing and climbing in the Alps, to visiting the historic cities of Provence, to horseback riding in the Camargue-have been key to the river's popularity. Navigation has always been carried on, particularly between Lyon and the sea, and the Rh^one traditionally has been the transportation funnel between northern and southern France; the Rh^one valley in Valais served a similar function in Switzerland, particularly with the construction of a number of rail and road tunnels under some of the mountain barriers.

The most extensive improvements to the river itself have taken place between Lyon and the Mediterranean: shoals have been submerged under the reservoirs created by dams or bypassed by canals, and the original gradient has been replaced by a succession of level reaches and locks. History (of RHONE River) Great cities attest the antiquity and the strength of people's interest in the region, which long ago was influenced by Celtic settlement and then by Roman domination. Brig, Sion, and Martigny in the Alpine section; Lausanne and Lyon on Lake Geneva; Lyon, at one of the major European crossways; and the Provencal cities of N^i mes, Arles, and Orange all contain evidence of their Roman past. From AD 1033 much of the region was controlled by the house of Savoy; ultimately, Valais, Geneva, and Vaud joined the Swiss Confederation, while Savoy itself became part of France.

During the 14th and early 15th centuries, Avignon (located just north of the Rh^one delta) was the residence of the popes of the Avignon papacy and antipopes of the Western Schism. The river, once a spearhead for the penetration of Mediterranean cultures and peoples into northern Europe, again became a route way for invasion, when Allied armies followed it north after landing in southern France during World War II.