From Switzerland to the Mediterranean: One of Europe’s Most Powerful Rivers | The Rhône

Its source is situated in Switzerland. For almost 550 kilometers, it flows through France before it empties into the Mediterranean. The Rhône. No other European river has been reshaped so much in the course of history. Nowadays, the question of its future arises. People no longer only see the Rhône's economic potential. Today, the focus is increasingly on its nature. Which is worth protecting. Mid-April. Winter is coming to an end in the Swiss Alps. For scientists at the Technical University of Zurich, the time has come to take stock of the glacier from which the Rhône rises. Glaciologist Matthias Huss measures how much snow has fallen during the winter. Climate change is also threatening the Rhône glacier, with consequences for the entire course of the river. You need the Rhône's water to irrigate fields. It also has an influence on river navigation further downstream, below Lake Geneva. It has been found that during the summer months, glacial melt makes up a considerable amount of the water in the Rhône. And when the glaciers are gone, we don't have this water. Dominik Greff checks a measuring device permanently installed in the ice of the glacier. This is called a seismometer. It's installed about four meters below the surface of the ice. We use the seismometer to measure what are called ice quakes. The ice quakes are like small earthquakes. They are caused by the fact that the glacier glides over the glacier bed. We can almost hear what is going on down there. Ultimately, this is important for predicting the rise in sea level. That is why it is interesting. There is almost 180 meters of ice beneath us. Sounds like a lot. Last year, we had about six meters of ice melting away here. This means that all the snow that lies here now is gone in summer, plus another six meters of ice. We don't see a clear tendency towards less snowfall in April, but more melting in summer. And that causes the glacier to retreat. And when the glaciers are gone, which we expect by the end of this century, at least to a large extent, then it could really be a problem that we have too little water in the dry summer months. Here in Valais, but also further downstream. In October, the scientists will return to the glacier to measure how much ice has melted over the summer. The Rhone arises in the Swiss Valais. It flows through Lake Geneva and, now already in France, separates the Alps and the Jura mountain ranges. It passes through the Lyon conurbation and, for a good 300 kilometers, shapes the Rhone Valley. Near Arles, it divides. Its two arms border the plains of the Camargue, where, after 812 kilometers, the Rhone flows into the Mediterranean. The Rhone loses its first 800 meters of altitude over a distance of only a few kilometers. It flows through the villages in the highest part of the Valais, in the Aubergoms. A train line connects the hamlets of Goms with Brig, a major junction, 40 kilometers further down in the Rhone Valley. The Rhone has always been a wild river. Again and again it changed its course, overflowed its banks. In the second half of the 19th century, people started taming it. Historian Muriel Bourgia is interested in the course of the Rhone, before it was corrected. Muriel works in the capital of the Valais, Sion. In the city archive, Muriel finds information about the first Rhone correction. It was carried out in order to reclaim land for agricultural purposes. These old plans show us what the old branches of the Rhone were like before the first correction, which took place between 1860 and 1893. We can see that even in the 1820s, they wanted to move the bed of the Rhone. We can learn a lot of things about how the land next to the Rhone was used. At that time, the river occupied a lot of space in the plain. And then gradually became more and more restricted, in order to cultivate and build on the land. The Rhone can still be dangerous. In the past, residents feared it because it could flood mainly meadows, pastures and some fields. Today though, if there is a big flood, houses and factories are being inundated. Between the 1930s and 1960s, the second correction shaped the Rhone according to the needs of the time. It was straightened more, with even higher embankments. For a few years now, the third Rhone correction has been underway. And it's not only intended to serve as flood protection. An architectural competition has been announced, for the Rhone banks of the future. People have really become separated from the Rhone. In fact, it has been so well contained, they have forgotten about it. And that is why I hope that, thanks to the third correction, people will be able to reconnect to the Rhone, a river that is nothing less than essential to the landscape. In some places, the third correction is already in progress. Engineer David Miche is in charge of the construction work in the Upper Vallée. For me, the river is a living space, a piece of freedom, and definitely a piece of home. Here is a place that we have already renatured. We have expanded the riverbed about 1.6 times. The river can now meander a little during the low-water periods, and it forms gravel banks. This is what you want from renaturation. If it gets a little greener around it, it looks even nicer. But I think that's the goal you set yourself. This river, this picture of a river, is actually a dream. This is my life, this is my passion. That's why I'm working at the third Rhone correction. It's my goal to bring the Rhone back to its roots a bit. We all know it won't always be possible. We would need a lot more space. You simply try to make the best of it. The third Rhone correction is the largest construction project in Switzerland. 160 kilometers of the Rhone bed is being redesigned, at a cost of 3 billion Swiss francs and a construction period of 30 years. This is where we're planning a selective widening, three times as wide as the Rhone is now. But the main objective is clearly flood protection. Recent storms have shown that if the Rhone is angry, it will burst its banks. And especially here in the industrial area, the potential damage is enormous. Statistically, the Rhone is subject to severe floods every 100 years or so. Dikes can overflow or even break, and this would cause devastating damage today. The last major flood on the upper reaches of the Rhone happened in the year 2000. The engineers can't do anything about dry summers. But the new Rhone is to be prepared against extreme flooding. The third correction will also make the river more natural again. And of course, I hope this is done for our future generations. If I ever have grandchildren, I hope not too soon, it would be nice if the Rhone returned to how it used to be. In the Pfinnvaard Nature Reserve, you can see what the Rhone once looked like everywhere in the valley. Gravel banks, unspoiled pine forest, a river that finds its own path. I think that's an interesting thing. This one piece will make 52 layers. Watch on mobile devices or the big screen. All for free. No subscription required. Fed by streams both large and small, the river slowly widens. After 160 kilometers, it flows into Lake Geneva. During the last great ice age, the Rhone glacier stretched for more than 500 kilometers all the way up to the Lyon region. When it retreated, it carved out Lake Geneva and formed its shores. In Lavaux, Cistercian monks started terracing the steep slopes in the 12th century. Today, 400 kilometers of walls support thousands of terraces, some of them tiny. A landscape that today is a UNESCO World Heritage Site. Tania Gfeller, a native French woman with Chilean roots, is the onology expert responsible for the five vineyards of the city of Lusanne. What defines the region here is this particular microclimate generated by the lake. Its water reflects the sun. The walls store the sun's heat. And then we have sun here all year round. That's why we speak of the three suns. This is an old glacier area that defines the whole shore region of Lake Geneva. The glacier has created a patchwork of different soil types. They come directly from the glacier. Tania works closely with vintner Luc Dubouloz, who coordinates the vineyard processes. When the ice retreated, it left all our soils in place. We have an entire glacial moraine under this ground. And that's what lends expression to our chasselas. The chasselas are very interesting. It is not a very aromatic grape variety in itself, but that is why it expresses its soil particularly well. It is thanks to the withdrawal of the Rhône glacier that we can enjoy this soil today. The Clos d'Abbaye is one of the oldest wineries on the lake. In this winery cellar, Cistercian monks used to press wine. It has been owned by the city of Lusanne since the 16th century. The chasselas is ready for bottling. Apart from chasselas, which is the grape variety of the region, we cultivate two other varieties, Syrah and Rouenier, which are types of grapes originating from the French Rhône valley. Tests were carried out to find out which varieties, other than chasselas, could thrive here. And it was amusing to note that the varieties that are developing well are from the Rhône valley. We like to say that we are also a little bit in the Rhône valley, but on the Swiss side, of course. Johannes de Graaf, born in the Netherlands, is one of about a hundred professional fishermen on Lake Geneva. Johannes fishes for whitefish and perch, grayling and pike, depending on the season. He had laid his nets out last night. It's like in any profession. If you love it and work hard, it's good. Of course, sometimes it's easier and sometimes harder. You never know in advance how things will go, whether you will catch something or not. But what is easy in life? It is not so easy with the weather. It changes constantly. And you never know if the pike are near the shore, at a depth of four meters, or if they are further down, at 18 to 20 meters, as they are now. You try to follow them in order to catch them. But it is not always easy to know where they are. The water in Lake Geneva is supplied almost exclusively by the Rhône. It oxygenates the water, which is important for trout in particular, but also for large predatory fish such as pike. I don't know exactly why, but I'm sure it has a great significance for the lake. The current at the bottom always flows in the same direction. So I think if you interrupted that current, the lake wouldn't work as it used to. Almost 80% of the water in Lake Geneva comes from the Rhône. If the lake were emptied, it would take 10.4 years to fill up again. That's how we know that the Rhône takes a good 10 years to flow through Lake Geneva. In the city of Geneva, the Rhône emerges from the lake again. How much water it carries is regulated by the Surgé Rier. It also controls the water level of the lake. Once it fluctuated by up to 3 meters depending on the season. Today, by only 60 centimeters. The flow of water into the Rhône is relatively constant. Here, the annual average is about 270 cubic meters per second. A few kilometers downstream from Lake Geneva, the Rhône crosses the border into France and passes the perhaps most pristine of the landscapes on its course. A good 500 kilometers still lie ahead before it empties into the Mediterranean Sea. The plan? Don't fall into the water. Yves Cornetto comes from a village on the upper reaches of a French Rhône. Together with his friend Yannick Seville, Yves wants to travel on a stretch of river that cannot be reached by road. The weather is actually nice and sunny, but there is a strong wind. In a narrow valley, where Fort Lecluse once guarded the border between France and Savoy, the wind turns into a storm. When we were in the gorge, the wind became really strong, wind force 8 or 9. You could hardly steer. We didn't want to take any risks and are now waiting for the wind to calm down and see what happens. A few kilometers down the river lies Génissia. In the 1930s, the Rhône National Company acquired the concession to use the river, mainly for power generation. Génissia is the first and oldest in a cascade of 19 power stations along the course of the Rhône in France. It took over 11 years to build. When the power plant was connected to the grid in 1948, it was the largest in Europe. In the small town of Cécelles, the Rhône flows through a wider valley, a section of the river that Yves particularly likes. The Rhône, it's a bit of a love story, because it's a river I've known since I was a kid. I first got to know it fishing with my father. Well, I was a bad fisherman. I was more interested in the Rhône than fishing. A few years later, I discovered kayaking, so I first rented and then bought my own. Then I could indulge my passion for kayaking and for the Rhône. It allowed me to rediscover the Rhône and my region all over again. We live in a competitive world. We are constantly on the lookout, running, or at least that is how daily life is for me. And kayaking allows me to recharge my batteries. I also created a blog precisely to promote a different approach to kayaking and to set up projects like traveling on the Rhône from Geneva to the Mediterranean, to help people discover the Rhône. And you find like-minded people who want to see things differently because the view from the water offers completely different perspectives from what we see in everyday life. Slowly leaving the mountains, the Rhône flows towards the west. Now and again fed by smaller tributaries, it has become wider and more powerful as it flows towards Lyon. Lyon is the largest city on the banks of the Rhône. Since Roman times, it has been a trading hub at the confluence of the Rhône and Somme rivers. Right in the center of the city is Porte Édouard Hériault, the Porte of Lyon. Captain Steve Becker has come down the zone. He bought provisions in Lyon and now he wants to go on. His son Kevin is also on board. Kevin is in training to become a river boatman. From Lyon, it's still 310 kilometers to the mouth of the Rhône in the Camargue. The Condor, 110 meters long, capacity 3,200 tons. A medium-sized freighter. At 41, Steve Becker is the youngest skipper on the Rhône. His son Kevin, 16 years old, is doing part of his training on board. Steve introduces him to the special characteristics of the river's course. The journey through Vienne is particularly tricky. The bridges produce whirlpools, which cause the ship to drift to the left and Kevin has to hold against that. He's highly focused. It takes at least a year or two to learn. I'm still learning, even after 20 years. There are small surprises and perils everywhere. A little to the left there. As they are approaching the locks, Steve takes over the helm. A lot of experience is needed here. Maneuvering the vessel in is a matter of centimeters. We loaded gravel in Macron. We have 2,600 tons of gravel that will be used as a base for railway sleepers. We're shipping it to Arles. It takes about 30 hours to get there, if all goes well. Then it depends on the locks. You see, it's already started badly. Already an hour wait at the first one. If we do this at each lock, it takes 40 hours. In 1934, the Rhone National Company received the exclusive concession to use the river for power generation, shipping and irrigation. After the Second World War, development began on a grand scale. Billions of cubic meters of soil were moved, hundreds of kilometers of dikes were built and 19 power stations constructed. For most, bypass channels were dug out. The principle is always the same. Once the canal has been dug, a power station with a lock is built and the old arm is cut off. Almost all the Rhone water then flows into the canal. Only between 1% and 5% of the water remains for the old bed. Before its regulation, the Rhone was up to three kilometers wide in some places, a meandering river with islands and small side arms, the so-called Ionée. Currently, the Rhone is being re-natured in many places. In 1986, work began on the island of La Platière, today a nature reserve that is managed by an organization. Once a year, botanist Bernard Pont examines how the island's flora is developing. On the banks of the old riverbed, in the transition zone between dry and wetland areas, Bernard conducts a plant inventory. For some years now, the Rhone company has been providing more water for the old Rhone branch. River obstructions that were no longer needed have been removed. Today, during high water, parts of the island are flooded again and the floodplain forest is flourishing. In this densely wooded area, which is about 350 hectares, we have 40 different species of trees. If you take an area of normal forest of the same size, which is not a floodplain forest, you will find two to three times fewer species in the same area. This forest floods regularly. Only plant and animal species that are adapted to that can be found here. So it is the flooding that allows this very particular forest to develop. And these forests can only be found in the large alluvial corridors. To reconnect dead arms with the river and to dig new arms, that is the main task of renaturation of the Rhone. Bernard takes note of how many species of plants and animals return and how quickly they do so. The fact that more water is being channeled into the old Rhone today has noticeable effects. What we can see today is a flowing river. We see a current. Six years ago, we would have come here and felt like we were on the edge of a pond. You couldn't see the water flowing. The first change that occurred was to increase the minimum flow rate in this arm, which had had water diverted away from it for the power plants. Now we have a flowing river again. This landscape that we have in front of us, with islands, small river arms and erosion slopes, is indeed completely new. And it is a very encouraging sign of new life for the river that is developing. Plans to extend the Rhone-Rhine canal to connect the Mediterranean Sea to the North Sea were buried in the 1990s, which explains the decline in freight traffic. However, the largest Rhone ships can replace up to 220 trucks. It's a small world. There are only 20 boatmen on the Rhone, so 20 boats over 500 kilometers, that's not much. It's a very environmentally friendly mode of transport, but unfortunately not used enough. It is underexploited. We could do a lot better. I transport 2,600 tons. That's equivalent to about 80 trucks, maybe a bit more. The government tells people to drive petrol-powered cars, but they let diesel trucks run all over the place. Well, there is a solution right here. The Rhone is empty. They need to get back to using the waterways. The entire Rhone Valley is densely populated. The vineyards of the different appellations of the Côte du Rhone extend over large stretches, right down to the riverbanks. It is the most water-abundant river in France. Forty stations pump water for agriculture and irrigate almost 200,000 hectares of fields and orchards. In France, it is fed by eight major tributaries. Four nuclear power stations are located on the banks of the Rhone and use its water for cooling. In summer especially, this is becoming more and more difficult. Overall, the temperature of the Rhone has risen by two degrees in the last 30 years. Global warming is also responsible for the overall decline in the amount of water. In a hot summer, one third less water flows than it did 20 years ago. Now comes the next lock, Boleyn. Depending on the water level, the chamber goes down up to 23 metres. Kevin has his eye on the ropes. And Steve has time to eat a snack. This is impossible when he's navigating. When it went into operation in the 1960s, Boleyn was the highest lock in the world. And its hydroelectric power station was the largest in Europe. Like all power stations on the river, Boleyn is operated by the National Rhone Company. With a capacity of almost 4,000 megawatts, it is the largest producer of renewable energy in France. The majority of what it produces comes from hydropower. But since the amount of water in the river seems to be going down, it is increasingly relying on sun and wind power. It all is on schedule. Steve did not have to wait at the last couple of locks. Good for him, but also a bad sign. I started here in 2000. Since then, the number of ships has halved. There were 40 freighters, and today there are only 20. Kevin? We'll see. There may be three or four young people following in our footsteps. That's all. And yes, of the 20 boats left, the average age of the captain is 50 to 55 years. That means in 10 years we'll have a big problem. We're going to stay on the Rhone a little longer. I don't know how long it'll last, but as long as there's work to do. When there's none left, we'll go somewhere else. As the Condor passes by the old papal city of Avignon, another 60 kilometers lie between them and their port of destination. The bridge of Avignon was built in the 12th century. It spanned both arms of the Rhone until floods destroyed it in the 17th century. Between the two arms of the Rhone lies the island of Bortelaz. La Ferme de la Raboule was founded generations ago and today is run by the founder's great-grandchildren, the brothers Clément, Mathieu and Numa Capot. Early in the morning, he is harvesting zucchini flowers. We only pick to order, only flowers that are already sold. This is better for us because we don't need to store them, don't have to keep them cool. It has many advantages. The alluvial soil is extremely fertile, but the island's position also holds risks. We are the fourth generation to farm the land and we have always lived with the risk of flooding and the whims of the Rhone. When my grandfather redid the pastry on the house, he marked all the flood dates. In 1994, the water was 7.10 meters. When the Rhone rises this high, it is called a centenary flood. In 2003, it was almost eight meters high and the highest one in 1856 was up there at 8.56 meters. Near Avignon, the Rhone usually carries about 1,700 cubic meters of water per second. During a normal flood, that increases to more than 4,000. During a centenary flood, this can go even higher to more than 11,000 cubic meters. A flood like that could easily wash away a bridge. Numa delivers his vegetables directly to some restaurants in the center of Avignon. The historic old town is dominated by the Papal Palace, seat of the popes in the 14th century. The Rhone city, with its famous bridge, attracts four million visitors every year. Today, more and more arrive on river cruise ships. The brothers cultivate more than 50 types of vegetables on 11 hectares of land. In one of the fields, in front of the bridge, the fennel is ready for harvesting. In the past, Barthelas was almost exclusively used for growing wine. Grapevines are very resistant to flooding. Before all the work on the Rhone began with dikes and dams, the island was flooded regularly. My grandfather led through 13 floods during the years 1968 and 1969 alone, when this turned into a lake for three months. But the vines continued to grow, and there were never any problems with phylloxera. They were drowned by the recurring floods. In 1985, subsidies for wine growing were cut. The farmers planted fruit trees instead, but these couldn't survive the flooding. The Capot brothers are now betting on vegetables. What is not delivered directly to restaurants is sold in the farm shop. Mathieu takes care of that. Direct sales is part of our family. It's in our genes. I've always seen it done by my father, and my grandmother used to sell directly out of the wine cellar. I can't imagine doing anything else, honestly. With their passion for the farm, the brothers accept that they have to clear the shop every now and then, often with very little time. Some floods come very quickly. From the time we get the warning to when the water comes, we have between four to six hours. During this time, we have to get ready for battle. First secure the agricultural equipment, then the living areas, and the fields. All harvests are lost. Nothing is edible. We have to destroy everything. All along the Rhône, there are relics of Roman antiquity. The most important port of the Roman colony of Gaul was Arrelate, Arles. The amphitheatre could hold up to 20,000 people. This is where the road from Rome to Spain crossed the Rhône. The port stretched one kilometre along the right bank. In the city's Museum of Antiquities, relics of its Roman past can be found. A few years ago, it had to be enlarged to make room for a find from the riverbed near Arles. Archaeologist Sabrina Malier was involved in the recovery, almost completely preserved, 31 metres long, a barge from the 1st century AD. It lay in the Rhône, buried under an ancient port rubbish dump, and it provides archaeologists with information about a cosmopolitan city of the Roman Empire, in Gaul. The discovery of these objects shows us that the number of boats that were going up and down the Rhône was huge. Arles was an extremely important port, situated at a major commercial crossroads. The river connected the north to the Mediterranean Sea, and important roadways like the Via Aurelia were also not far away. It operated in connection with its maritime port, which is today Fos-sur-Mer. This port complex, formed by Fos-sur-Mer and Arles, was the second most important Mediterranean port of the Roman Empire, after the Roman port of Ostia. The sea port facilities are currently being surveyed and mapped. Archaeologists are working with geomorphologists, who are familiar with landforms. Today, several of us will be in the water, measuring the size of stone blocks belonging to a huge building, maybe 100 by 100 meters. So it's a rather technical dive. The researchers want to find out what the building used to be, whether it was part of the port, or perhaps a temple. They go down to the ruins of an ancient city, three to four meters below sea level. Underwater, we find all the remains of this economic commercial activity and navigation. But there are also thousands and thousands of amphoras and ceramics, as well as everyday objects that may have been lost, like men's sandals, soldiers' swords, women's jewelry. It is a treasure trove of information for archaeologists, not only about the city in Roman times, but also about trade in the Mediterranean region. The water level has risen by 60 centimeters since Roman times. This does not explain why the ruins lie at a depth of four meters. The delta has indeed been changing for millennia, also since antiquity. Sometimes the land rose up and sometimes the water pushed back. In addition, the number of arms of the Rhône has varied since antiquity, but we probably also have tectonic movements that could explain why the buildings are submerged today. This is what we archaeologists are trying to understand, with the help of the geomorphologists. The Rhône delta begins at the city of Arles. Here, the river divides into the Great Rhône and the Little Rhône. Thirteen percent of the water flows into the Little Rhône. Most of the water reaches the sea via the Great Rhône, which is also used by cargo ships. The two arms border the Camargue, the humid alluvial plain that would not exist without the Rhône. Large areas are strictly protected. Others are being used for agriculture or salt extraction. On the banks of the Great Rhône lies the Domaine de Beaujeu. Together with his son, Julien-Pierre Cartier cultivates about 160 hectares. He grows wet rice on alternating areas. Before the Rhône arms were dammed, they regularly flooded the Camargue plain, the fresh water preventing the soil from becoming too salty. Today, 200 rice farmers pump up to 400 million cubic meters of Rhône water onto their fields. The Rhône is very important for us. Everything we grow has to be irrigated. This is especially true for rice, of course. And the fresh water in the rice fields desalinates the soil. We now notice that the Rhône has less water, even in winter. Fewer floods and a lower water level. Pierre must maintain dozens of kilometers of irrigation channels. A lot of work for a small family business. Wet rice emits methane and is therefore actually bad for the climate, but important for the Camargue. Without irrigated rice, agriculture would have no long-term future here. Rice has been grown in the Camargue for a long time. Sometimes more, sometimes less. At the moment, areas are shrinking, mainly because subsidies from the EU have been abolished. And now crops are being planted that are ecologically harmful. Tomatoes, melons. Rice, I think, is better for the ecology of the Camargue than the new varieties that are now being grown. All areas the Rhône flows through are man-made cultivated landscapes. And in parts very fragile, like here in the Camargue. Agriculture in the Camargue allows a balance to be maintained if the water is distributed evenly and the necessary amount of fresh water is supplied. Without this water management, the Camargue would once again become a wilderness, a salty wilderness. So, of course, we hope that the Rhône will continue to provide us with the fresh water we need. The Camargue, created from Rhône sediments, nourished by Rhône water. More people, in Switzerland and in France, see the Rhône not only as a driver of economic development, but increasingly as a river worth protecting and preserving. After 812 kilometers, the Rhône has finally reached its destination and flows into the Mediterranean Sea.