Trend: The world’s cities are digging up their old rivers



– Yes, it’s the valley! The quiet and dark valley! Here, the cooler summer blooms in the shade. Here the fleeting flowers last a long time… This is how the French romantic writer Victor Hugo wrote in a poem about the river La Bièvre, which in the 19th century wound its way through Paris. But the poet perhaps already sensed at the time that the valley would not always remain lush, because in the same poem he also rages against the “crazy and narrow world where man every day gives less space to God!” At least there was less room for the river. Paris grew and eventually Bièvre was buried under the city’s asphalt and traffic. In 1912 it was completely covered. Many other of the world’s rivers and streams have suffered the same fate as Bièvre’s cool valley of flowers. Especially during the 20th century, many towns’ streams were hidden and forgotten. The waterways were laid in pipes underground and this was mainly due to the fact that more space was needed to get cars into the cities. But today the river Bièvre is on its way back into the light. It has been excavated again in three sections, and the city council in Paris is planning how a further seven sections can be excavated. Read the poem Bièvre There is a movement underway The project has not only started because of romantic thoughts about the past, but to a large extent also because of practical thoughts about the future. We are now living in a time of global warming, and in the summer Parisians sweat extra heavily in the heat because the temperature inside the city is as much as eight degrees higher than in the surrounding countryside. The evaporation from the water and the trees along the river will help keep Paris cool. At the same time, the open river will help to channel the water away when there are cloudbursts. The problems are global and so are the solutions. In many other places in the world, the cities now also want the streams to return to the surface. They cut in roads and car parks and dig up the watercourses again. In English, it is called “daylighting” because the water must rise again in the light of day. Anna Aslaug Lund, landscape architect and assistant professor from the University of Copenhagen, has, among other things, researched how we can use nature’s solutions to secure our cities against cloudbursts, which are becoming more frequent as a result of climate change. She also believes that daylighting is a trend that is moving forward. – There are so many incredible projects right now in connection with this, and many of the projects are about bringing streams and water inlets to the surface. You can also say that it is part of a general movement in the direction of creating more space for nature in the cities, says Anna Aslaug Lund. Several cities are successful in inviting nature in Among other things, she mentions the South Korean capital Seoul, which has been successful in digging up an old river again. It has created an oasis in the middle of the busy city. – I have visited the place in connection with my research, and it has really become a popular area where there are many people even late at night. Part of the river has a more urban character, a bit like the Aarhus river (in Denmark, editor’s note), which is also a river that has been drawn up to the surface. Gradually it becomes more natural and gets more vegetation such as bushes and trees. It is a success story, says Anna Aslaug Lund. She also mentions another project located in the city of Portland in the US state of Oregon. Here, the city has dug a former wetland back to the surface, and in doing so created a park called Tanner Springs Park. In New York, the borough of The Bronx now has plans to bring back a river called Tibbet’s Brook and free it from the sewer system. And in London, according to Anna Aslaug Lund, there is “almost a whole movement” to bring some of their old underground rivers back to the surface. – In general, there is a movement around experiencing the city as part of the landscape. And it’s not just a discussion we have among landscape architects. When I talk to friends and family, it is also something that more and more people can see the quality that it is actually nicer to live in a city where there are trees along the streets, or that an asphalted car park is converted into a park. So I see it as a very big movement, she says. Fewer roads and more rivers can make traffic flow According to Anna Aslaug Lund, it is often a difficult balancing act how much space to give to nature in a city where many people live. But sometimes there can be surprising benefits from giving nature more space. For example, the traffic situation in Seoul actually improved when a freeway through the city was closed to make way for the river. The explanation is complicated, but it is about the fact that sometimes it actually makes traffic worse when there are more roads, because it causes motorists to “clump” together in certain places. – Overall, I also believe that we have to step back and look at whether we really want to have so many cars in the cities. It is clear that there will often be some residents who are against the individual project, because their local car park might be taken away from them. But in the places where old water inlets have been dug up, you have got an enormous amount of recreational qualities out of it, concludes Anna Aslaug Lund.



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