Nile River in Egypt: Nile Delta, River Cycles and Why the Valley is So Fertile

by Gerald Green

The Nile river does more than provide water for Egypt.  It is responsible for its fertile black soil.

Every summer, just when you would expect a river flowing through hot rainless deserts to dry up, the Nile rises. 

By autumn, it is so high that it overflows its banks, drenching the land. 

In December, the river returns to normal.  But as it does, it leaves behind a rich deposit of earth, or silt.  This earth is so fertile that it yieds two or three crops a year, if properly watered. 

How does the Nile do this? 

Well, one of the sources of the Nile is in the mountains of Ethiopia.  Heavy summer rains turn the Blue Nile into a torrent.  (The Nile can be seen as two rivers;  the White Nile which starts in Central Africa, and the Blue Nile, which rises in a sacred spring in the mountains of Ethiopia.  As the river runs North, there is a third tributary, the Atbara river.)

Above:  Blue Nile Falls

The Blue Nile flows down the hillsides with such force that it scrapes off the topsoil.  This mass of water and soil rushes on to meet the White Nile.  The combined stream carries tons of soil thousands of miles into Egypt. 

Over the years, the river has built up a rich valley varying in width from a few yards to 15 or 20 miles at the most.  Near its mouth, it has made a wide fertile area called the delta, because it has the triangular shape of the fourth letter of the Greek alphabet. 

The Nile Valley and its delta comprise only three per cent of Egypt's land today, but 95 % of the population lives there!

Above:  This photograph taken by NASA of the Nile delta at night, clearly shows how all the lights, translating as the population living there, are concentrated along the Nile and its valley, with the most lights in the triangular shaped Nile delta. 

This is practically the only fertile area in the country. 

The early Egyptians built their villages on the outer edge of the river valley, so they would not cover good soil with houses.  They called their country "The Two Banks".  Their definition of an Egyptian was "any man who drinks from the Nile".