Is Taming Rivers a Good Idea?

Rivers, in many parts of the world, are often straightened, deepened and widened. The intention is often to increase the amount of usable agricultural land in the vicinity. In other cases, the increased water flow may be used to generate hydroelectric power. There is accumulating evidence, however, that this river 'taming' can result in problematic downstream flooding (https://www.theguardian.com/science/2021/mar/03/rewild-releasing-britain-rivers-flooding). A good example of this effect of river 'taming', is provided by a Salford University study on the River Caldew in Cumbria (in Northwest England). Here, the engineeered changes to the river, greatly increased the amount of sediment carried downstream. This sediment caused blockages, directly linked to repeated damaging flooding events in the city of Carlisle. Similar effects of river changes have also been seen in the Canterbury Plains region of New Zealand. When flooding events occur, there is generally a local demand for the rapid creation of flood defenses. Some experts believe that 'rewilding' the rivers will be a more effective solution. It is important to devise the most effective strategy for rivers, as climate change is making flooding a much more common phenomenon.