The complete disappearance of any river is not an easy thing to predict, because there may be a lot of factors pertaining to the extinction of a river. Setting aside the ill affects on the rivers caused by the growing human population and industrialization, there are also these geographical and natural factors, which can greatly affect and alter a river's current state including the earthquakes, floods, movements of tectonics plates or any unpredictable change of climate set to be occurred in the future.
As the history indicates, in 4000 B.C a great river naming Saraswati flowing in North-west India was completely disappeared. The current research and Satellite images predict the river to be flowing once from the Siwalik hill at the Himalaya foothills in Himachal Pradesh to the Arabian Sea. The research started on this river when an English engineer called CF Oldham firstly pointed out the unexpected wide bed of a small seasonal river in Rajasthan in 1893. This small river named Ghaggar, which is expected to be one of the tributaries of the river Saraswati has a valley of eight to twelve kilometers of width in Haryana. Most of the people in India believe the existence of Saraswati river because of its strong reference in the Vedas and the ancient Hindu mythology. Scientists and Geologists relate the extinction of this river to the major changes in tectonic plates around the Himalayan area thousands of years ago that cut off the supply of melting ice water from the source. The diversion of this river and the gradual separation from its tributaries left it with several lakes and pools those dried out eventually.
Presently the threat to any rivers' existence comes mainly from the irrepressible growth of human population and its affect on the environment. As the population increases, so is the demand for water. The major rivers in this world including Yangtze and Yellow river of China, Nile in Africa, North America's Rio Grande and the Ganges and Indus of south Asia all are badly affected by pollution and global warming. Yangtze river is supposed to be receiving half of China's industrial waste. Volga river in Russia is another example that is being polluted due to the large number of industries situated within its drainage. As the water gets polluted the marine life is suffering and the fish production deteriorating. In North America the depleting water level in Rio Grande and the percolation of salt water bringing in the ocean species that endanger the lives of fresh water fishes. Due to unusual climate condition of global warming some rivers that used to flow throughout the year are running dry for a season or two .The depletion of water levels are caused by diverting the river to build dams or to use them for irrigation purposes. Sometimes after being used extensively in the upstream areas these rivers can not even flush out properly in the Sea, which influences the environmental and ecological advantages. Colorado river in US is rarely reaching out to the Sea and as the water runs dry the fishery production is degrading. Rivers in Asia like Ganga, Indus cannot make it to Sea in the dry seasons. Ganga that is considered to be a sacred river in India is now a victim of the country's bursting population and is facing the challenge of being one of the most polluted river in Asia.
As the demand for water is increasing day by day, sooner or later the world will be water deficit. In northern china water table is falling at an approximate rate of five feet in a year. Increasing number of water pumps and the rising need of drilling aquifers is resulting scarcity of underground water. The demand for electricity has made us dig out the underground sources and build geothermal power plants. The rate of usage of water in agriculture, power production, industries is much faster than the process of precipitation. The lands those were fertile are becoming barren. Due to global warming Rainfall has become intermittent. Sometimes the rivers go dry and the other time they are flooded. Due to wide spread settlement of human civilization forests are being cut resulting to soil erosions, floods, draughts, forest fires and other natural calamities.
Rivers in this earth have a future similar to us. If rivers dye, we can not survive. The world should be well aware of this fact. A serious approach to control population is the major demand of this hour. If population is regulated, so is the scarcity of water and the global warming. Water should not be wasted and more importantly should not be polluted. Industrialization makes us prosper, but over industrialization hampers our success. Rivers have been the lifelines for the sustenance and development of human civilization. They have provided us with food to live and guided us through the way to prosper. It is our turn now to understand the challenges Great rivers in this world face and it is our responsibility to make them flourish.