Throughout history, human societies have been greatly influenced by the presence andaccessibility of natural freshwater reserves. Where water is scarce, many nomadic communities (e.g. the San of the Kalahari and the Aborigines of Australia) migrated from one source toanother. In contrast, where water is more plentiful, many communities developed strategies tocope and even benefit from periodic flooding (e.g. the Halpulaars of the Senegal River basin).In the past, most human settlements were located where reliable water supplies could be relatively easily obtained from springs, rivers or shallow groundwater. However, as thepopulations of towns and cities grew, supplies from local rivers and wells could not satisfy theincreasing demand for water. In attempts to control water resources, humanity has manipulatedfreshwater systems for thousands of years. Civilizations have flourished where human ingenuityhas enabled food surpluses to be derived as a consequence of water management strategies.For example, the Sumerian, Egyptian, Mayan and Aztec civilizations were all dependent onelaborate schemes for controlling water supplies.
Until very recently, water management has focused primarily on the direct provision of water topeople for domestic purposes, to grow their food and support industries. Where water is scarce,one option is to supply it from elsewhere. In the Middle East, water transfer tunnels have beendiscovered that are almost 3,000 years old, and some of the most impressive monuments of theRoman Empire are the aqueducts constructed to convey water over long distances.An alternative to transferring water is to store it in times when it is naturally plentiful, for use attimes when it is scarce. Dams are constructed to store water. The earliest known dam was builtin Egypt 4,500 years ago to store water on a river that only flowed occasionally. The Mareb dam,built in Yemen 2,500 years ago, was one of the largest and most spectacular feats of civilengineering achieved by humanity in pre-modern times. The reservoir stored enough water (55Mm3) to irrigate about 10,000 ha of farmland and supported a population of between 30,000 and50,000 people. These are some of the earliest examples of water resource managementattempting to increase supply to meet demand, rather than constraining consumption to matchlocal availability.
Water has long been used as a source of energy, beginning with the Greeks use of water wheels over 2,000 years ago. For over a century, hydropower has been used to generate electricity.Hydroelectric Power -- what is it?It is a form of energy … a renewable resource.Hydroelectric powerplants do not use up resources to create electricity nor do they pollute the air, land, or water, as other powerplants may.Hydroelectric powerplants do not use up resources to create electricity nor do they pollute the air, land, or water, as other powerplants may.Both small and large hydroelectric power developments were instrumental in the early expansion of the electric power industry.Hydroelectric power comes from flowing water … winter and spring runoff from mountain streams and clear lakes. Water, when it is falling by the force of gravity, can be used to turn turbines and generators that produce electricity.
Until very recently, water management has focused primarily on the direct provision of water topeople for domestic purposes, to grow their food and support industries. Where water is scarce,one option is to supply it from elsewhere. In the Middle East, water transfer tunnels have beendiscovered that are almost 3,000 years old, and some of the most impressive monuments of theRoman Empire are the aqueducts constructed to convey water over long distances.An alternative to transferring water is to store it in times when it is naturally plentiful, for use attimes when it is scarce. Dams are constructed to store water. The earliest known dam was builtin Egypt 4,500 years ago to store water on a river that only flowed occasionally. The Mareb dam,built in Yemen 2,500 years ago, was one of the largest and most spectacular feats of civilengineering achieved by humanity in pre-modern times. The reservoir stored enough water (55Mm3) to irrigate about 10,000 ha of farmland and supported a population of between 30,000 and50,000 people. These are some of the earliest examples of water resource managementattempting to increase supply to meet demand, rather than constraining consumption to matchlocal availability.
Water has long been used as a source of energy, beginning with the Greeks use of water wheels over 2,000 years ago. For over a century, hydropower has been used to generate electricity.Hydroelectric Power -- what is it?It is a form of energy … a renewable resource.Hydroelectric powerplants do not use up resources to create electricity nor do they pollute the air, land, or water, as other powerplants may.Hydroelectric powerplants do not use up resources to create electricity nor do they pollute the air, land, or water, as other powerplants may.Both small and large hydroelectric power developments were instrumental in the early expansion of the electric power industry.Hydroelectric power comes from flowing water … winter and spring runoff from mountain streams and clear lakes. Water, when it is falling by the force of gravity, can be used to turn turbines and generators that produce electricity.
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