The Blue Nile is one of the sources for the great Nile River, contributing more than 85% of the total Nile river water. Beginning at Lake Tana (the largest lake in Ethiopia), the Blue Nile runs across Ethiopia and into Sudan where it connects with the White Nile at Khartoum.
The Blue Nile runs between 850 and 907 miles or so. The difference in distance is a result of the gorges the river runs through, some being as deep as the Grand Canyon. Along with gorges, the river passes through rapids, canyons and lakes.
The flow of the river is caused by the Tis Issat Falls, where millions of gallons of water spill over the 145-foot high falls. The river flows at its greatest between the months of June and September, the rainy time of year.
During the rainy season Lake Tana floods, pushing more water down the Blue Nile, causing it to flood over as well. However, unlike most floods, this flood is welcome. This yearly flood provides water for the crops and fresh, rich top soil for planting new crops.
Since the times of the Ancient Egyptians, the Blue Nile has provided life, food and transportation for those who live along the Nile Valley.
Best wishes.
Sincerely,
-Liane Schmidt.