The River Runs Deep
Great poets all over the world have written about rivers, and why not? On their epic journeys from mountain to sea, they nurture and provide, shaping both our landscapes and our cultures. Irrigation has allowed for agriculture to flourish and provides hydration for millons. Rivers are also a mighty sight to behold, often carrying with them great cultural and religious significance, and history that is encapsulated in every drop.
This natural flowing watercourse usually flows towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of water. A river begins at a source (or several sources), follows a path or a course, and ends at a mouth, or several mouths. The water in a river is usually confined to a channel, made up of a stream bed between banks. In larger rivers, there is often also a wider floodplain shaped by flood-waters over-topping the channel. Floodplains may be very wide in relation to the size of the river channel. This distinction between the river channel and floodplain can be blurred, especially in urban areas where the floodplain of a river channel can become greatly developed by housing and industry.
By depositing nutrient-rich sediments to floodplains and deltas, rivers have produced some of the world’s most fertile agricultural land. Just about every civilisation has its origins in line with a major river – Mesopotamia’s Tigris-euphrates, Egypt’s Nile, and China’s Yellow and Mekong rivers for instance. Rivers are the most biodiverse ecosystems on the planet. Even though they contain 600 times less water than oceans, rivers and lakes collectively support more fish species, and freshwater fisheries provide the main source of protein for more than 500 million people worldwide.
The master key unlocking these healthy aquatic environments is “flow”. Well-connected river ecosystems allow an essential exchange of water, nutrients, sediments, and species that not only foster enormous biodiversity but also regulate sediment levels, flooding, pollution, and water purification.