In today's circumstances, we need a global management of water. World water demand is of course less than world water supply. Yet, water demand from sectors such as agriculture and other industries has been increasing very rapidly. The problems that emerge from the situation therefore indicate to the nature of water demand. As suggested earlier, there will be water scarcity at least in 30 countries the world over by the year 2000. Hence, to improve the availability of water and also the quality of water, proper management is a necessity. There are at least two significant means in water management that need to be looked into. They are:
1. Investing on the activities that help store water from the hydrological cycle and related activities such as dams; and
2. Demand management is making efforts to get water supplied where it is needed.
Building dams across the rivers try to satisfy multiple demands at the same time. Flood control, improving hydroelectricity generation and other uses of water including of irrigation are all included in this activity. The dams are also useful as multipurpose resources, freshwater fish, prawn cultivation and recreation resources. For example, the Aswan Dam in Egypt has been a good effort at national development. It provides for 50 per cent of the national demand for electricity and also gives protection from the floods. There are also negative impacts. There have been, for example, heavier clayey and sandy sediments, amounting as much as 100 million tonnes, deposited in the command area. The dam which once made the lands of the command very fertile causes sediments in the Nasar Lake.
As a result, to provide nutrients to make the lands fertile enough for production, the import of fertilisers has been on the increase. Besides, the brick kiln operators of Cairo do not get adequate raw materials for their brick production. It has also been found that the nutrients that were supplied to the sea from the Nile have now become scarce or even rare. The delta has gradually been receding over the years. Land salination and water-logging have increased, causing a degardation of land. The Food and Agricultural Organisation (FAO) of the United Nations has estimated that 35 per cent of the land in Egypt has been affected by salination while 90 per cent of the land in that country has been water-logged. This brings us to the fact that in water management, basin management is the foremost in importance.
In half the countries of the world, the demand for water would double by the year 2000 due to population growth. The pressures emanating from this fact would hasten the problems of the basins. This impinges on other resource problems in our lives. It is therefore important that the river water is a significant part of the water management efforts, too. This is also important for the reason that a problem affecting one part of the basin would automatically affect other parts of the system: an event occurring at one end of the river would impact upon the other end of the river.
River basin, like other resources, should be shared. Hence, water management through participatory approach would provide benefits for all people in the basin. Just as there are conflicts in 148 of the 200 major river basins, there are opportunities in all of these for integrated efforts at management. As of now, however, several countries have transformed their problems into crises. At the global level, there are only a few countries which cooperatively and understandingly approach the problem for solutions. From the experiences and successes of these countries, participatory approach emerges as the most effective for resolving the problems.