Rivers: The Netherlands are created as a kind of rubbish tip
As is known, water always runs to the lowest point. That is also the case in nature. If a lot of water flows from a certain area to a low point, a water channel is formed automatically, called a river. That river itself also runs to the lowest point, so that rivers that have developed in a higher area automatically flow to (in many cases) the sea. But before the water reaches the sea, the water that has fallen as rain into a river basin is added to it. Thus, a small stream that started in the mountains can grow into a very wide river before it flows into the sea.
But not all rivers flow into the sea. A number of them flow into another river and are then called tributaries or tributaries that also belong to the catchment area of a river. A river can also flow into a swamp or lake.
Catchment areas in the Netherlands
A catchment area refers to the area through which the water is drained. That water can come from a melting glacier or consist of rain. The size of the catchment area naturally also determines the amount of water that can be discharged. The Netherlands has two important large catchment areas, namely the Maas and the Rhine. Other river basins are formed by the Ems in the northeast and the Scheldt in the southwest. Other catchment areas of Dutch rivers have been dammed from the Middle Ages, such as the Hollandse IJssel, Linge and Oude Rijn.
Meandering and weaving rivers
With rivers, a distinction can be made between meandering rivers and braiding rivers. A meandering river has only one channel that can meander through the landscape in bends. A braiding river has several stream channels that can flow intertwined. Meandering rivers are mainly found in flat and low-lying areas. This is certainly the case if the discharge of the water is fairly constant. Rivers in mountain areas are often braiding rivers. They have small catchment areas and the discharge of the water can vary greatly throughout the year.
Origin of water
In nature, a river has the clear function of discharging excess water. The water that eventually forms the river has three origins, namely springs, glaciers and rain.
At sources the underground water comes up, such as seepage water. A seepage mainly occurs when an underground water flow flows from a higher area to a lower area. Seepage water is often the source that can be the start of a river.
A glacier is a mass of ice that once started like snow. If the snow stays long enough, it turns into ice. But that is only possible at a high altitude with a low temperature. Yet in the summer months, parts of the glaciers formed by snow that fell in the winter period melt and can thus form the beginning of a river.
Rain that falls frequently throughout the year always seeks the lowest point. If enough rain comes together there, a river is formed automatically.
Very long rivers
Rivers can reach considerable length. The longest river on earth is the Amazon with (depending on the different measurements used) between 6259 and 6800 kilometers in length. Of the rivers in Western Europe, the Rhine is the longest with 1320 kilometers, followed by the Maas with 900 kilometers and the Scheldt with 350 kilometers. The Rhine is a meltwater river that is initially formed by meltwater from snow and thawing glacier ice. The Maas, on the other hand, is completely dependent on rainwater. The height of the water levels largely depends on the season (melting snow and ice) and how much rain falls in a certain period.
Kind of garbage dump created by rivers
The Netherlands actually originated as a kind of garbage dump in Europe. In the past, sand, gravel and other erosion material was continuously brought in from distant mountain areas and left behind in the Netherlands. This is how the land was created layer by layer. In the distant past there was repeatedly talk of a large river plain through which raging rivers flowed. In particular, it is the dikes that now keep the rivers in check. In recent decades, however, attempts have been made to give the rivers more space again in the context of nature development.
Sediment according to flow rate
The transport of sand, gravel and other erosion material partly depends on the flow speed of the water. If the slope at the beginning of the river is large, larger chunks can sediment (deposit). Smaller and lighter particles are further carried by the water. As the river slows down towards the sea, more and more heavier material disappears and only the light is carried further along.