There are many advantages of forming a civilization on a delta or near a river valley. One advantage is that there is plenty of fertile soil for farming. Hunters and gatherers needed to be able to produce their own food. In Mesopotamia, the Fertile Crescent, the Tigris and Euphrates flood and deposit rich soil for farming. Eventually, the farmers learned to irrigate the river water, which led to surplus food supplies. In Sumer, which is located on the delta of the Euphrates, the Sumerians were able to produce so much food that they did not need as many farmers.
This led to division of labor, the specialization of jobs amongst the people. Instead of farming, a person could be a merchant and engage in trading surplus supplies. Now, the people can acquire things that they can not produce for themselves. Another advantage is that the people will have access to water, a natural resource. Water is needed for survival. People need water to drink, cook, and bathe. Other natural resources include straw and water. The Sumerians mixed sand, water, and straw to make mud bricks. They used the bricks to make homes and other buildings such as ziggurats, religious structures.
A third advantage is that the people can use the river to travel and trade. For example, the Egyptians use the Nile to transport their surplus supplies to the Mediterranean Sea or Isthmus of Suez, a major trading area connecting Africa and Asia. The Nile River flows north, so the Egyptians would not have to work as hard transporting their supplies. In the Huang River valley, the people use the Silk Road for trading. They transported their goods over land to the Mediterranean Sea where they traded. Finally, the natural barriers around these ancient river valleys are important because they protect the people from invasions.
Over irrigation creates a shortage is water. As more and more farmers irrigated their land, the water supply decreased. In Mesopotamia, this became a major source of conflict. Eventually, the dispute over water led to the downfall of Sumer. Another disadvantage is flooding. Flooding damages crops and buildings. Flooding also prevents farmers from working. In Egypt, the river floods every year, thereby, preventing farmers from planting their fields. Although these are major concerns, the advantages of living in a river valley have far more advantages.