Rivers and how it flow

The recent phenomenon that has been happening all over the world and has been affecting millions of people around the globe is all about the floods.

Nowadays, as we observe, floods are a bit different from the previous floods we have had experienced.

One factor for this is the overflowing waters from the rivers. Let us have an overview of what rivers are and where do they start and where do they end?

Rivers come in lots of different shapes and sizes, but they all have some things in common. All rivers and streams start at some high point. The high point can be a mountain, hill or other elevated area. Rivers begin in mountains or hills, where rain water or snowmelt collects and forms tiny streams called gullies. Gullies either grow larger when they collect more water and become streams themselves or meet streams and add to the water already in the stream. The merging of one stream to another is known as a tributary. As the water flows down, it may pick up more water from other small streams, springs or from rain or snow melt. These streams may slowly join together to form a larger stream or river.  Small rivers and streams may join together to become larger rivers. Eventually all this water from rivers and streams will run into the ocean or an inland body of water like a lake.

Leaving the high elevations of the mountains and hills and entering the flat plains, the river slows down. Once the river slows down, the pieces of sediment have a chance to fall to the river bottom and be "deposited". These rocks and pebbles are worn smooth and get smaller as the water continues flowing.

Most of the sediment deposition occurs in the plains. The wide and flat valley of the plains takes thousands of years to create. Here, the river flows slowly, making S-shaped curves which are known as meanders. When the river floods, the river will spread out over many miles on either side of its banks. During floods, the valley is smoothed and tiny pieces of sediment are deposited, sculpting the valley and making it even smoother and more flat.

Eventually, a river flows into another large body of water, such as an ocean, bay, or lake. The transition between river and ocean, bay or lake is known as a delta. Most rivers have a delta, an area where the river divides into many channels and river water mixes with sea or lake water as the river water reaches the end of its journey.

From the mountains to the delta, a river does not just flow - it changes the surface of the earth. It cuts rocks, moves boulders, and deposits sediments, constantly attempting to carve away all of the mountains in its path. The goal of the river is to create a wide, flat valley where it can flow smoothly towards the ocean (source: Basic Geography of Oceans and Rivers).

Taking good care of our rivers as well as our creeks and allowing passage could somehow prevent too much flooding to happen in the near future.