Stormwater is also a resource and important as the world's human population demand exceeds the availability of readily available water. Techniques of storm water harvesting with point source water management and purification can potentially make urban environments self-sustaining in terms of water.
Rivers flow downhill to sea level (generally speaking; some end in other bodies of water or join another rver). They flow with gravity from a higher elevation to a lower. The Nile rises on the western flank of the Great Rift Valley (many people consider Lake Victoria to be the source) and the Blue Nile joins the White Nile at Khartoum. The land falls away towards the north, thus the river flows north until it reaches the Mediterranean Sea at the Nile Delta. Direction of flow of a river is determined by elevation of the drainage basin, not geographical (North, South etc.) direction. http://en.wikipedia.org/wiki/Nile#Course.
1 Nile river is 4184 miles long. 2  The Nile Riverâs average discharge is about 300 million cubic metres per day. 3  Crocodiles are very common along the banks of the Nile River.4  Fishing Eagles are a common bird along the Nile. 5  The Nile stretches north for approximately 4,000 miles from East Africa to the Mediterranean. The length of the river is approximately 6695 km and the river has two tributaries. 2  Only 22% of the river passes through Egypt, the other countries through which Nile passes are Sudan, Burundi, Ethiopia, Zaire, Kenya, Uganda, Rwanda and Tanzania.