Water is one of the most essential elements of Human Life, for its development as well as the environment. However, Water is termed as a finite and susceptible resource having quantitative constraints and qualitative vulnerability. Water is an indispensable source of life and its development on earth. Even though water is a regional source, its scarcity has become a global concern with ever increasing population, economic development, and global climate changes. It is broadly realized that several nations are entering an era of serious water famine.
Difficulty in purification and costly to transport, water is an essential constituent of life. A growingly scarce commodity is renewable water and practically there is limited amount of fresh water accessible to people. The common goal is to ensure that sufficient supplies of good quality & non-contaminated water is maintained for the global population, whilst making it certain that the hydrologic, chemical, and biological functions of ecosystems are preserved. Insufficient water results into a greater decline of economic development and gives rise to conflict over scarce resources. Instabilities in the hydrological cycle have led to local and regional water shortages. However, research has shown that from a global scenario, the entire hydrologic cycle is approaching the limits of usage and hence, countries with ample water supply will eventually start experiencing water scarcity. The United Nation (UN) has specifically put emphasis on the concern of water shortages and hygiene for the following reasons:
1. The ever shrinking levels of the subsurface water table across all the continents of the globe
2. Ever increasing global pollution of sub-surface and surface water
3. Saline agricultural land
4. As many as 45 crore of total population in 29 nations live in water-famine regions
5. Almost half of the world’s total population does not have water purification plants
6. Over 100 crores of people cannot access safe and purified drinking water
7. Approximately 70% of fresh water is utilized for irrigation purposes of agricultural land, which has elevated water conflict amongst the rural and urban areas.
If the above scenario continues, then by 2025 or even earlier almost half of the global population will be forced to encounter water scarcity issue. Researchers predict that the 21st century will witness the onset of the water wars. Furthermore, since water being unevenly spread across the lands, it influences inter0state and international relationships and hence the reason for hydro-politics. The planet’s ever expanding population with its multifaceted activities that demand fresh sanitized water is now posing serious threats to the availability of this vital resource. By 2025, the United Nations predicts that almost 1/3rd of the global population will witness a chronic water deficit, if the existing rate of consumption continues. Agricultural industry has been recorded of 70% of total water usage. The industry and energy sector records 23% of water consumption, whereas only 8% has been reported by household water usage. Nonetheless, these records vary depending on various nations and their levels of development, population size and climatic conditions. As far as solutions for this serious issue is concerned, global climate models or GCM, also known as continental hydrologic models have been devised on the basis of global climate datasets described by (Asante, 2000). Vorosmarty, Fekete, and Tucker (1996), Alcamo et al. (1998), Miller, Russell, and Caliri (1994), Asante (2000), and Lohmann, et al (1998) devised frameworks to be applied for the accurate calculation of water shortages and runoff at the continental and global level, and are capable of providing runoff creation and water balance at a range approximately 10,000 sq. kilometres. The models also allows for the extraction of runoff at the river basin scale. Various overviews of global water resources have been issued on the basis of these global databases and frameworks and studied records. Margat (1995) developed a series of global mapping patterns that indicated territorial variability of several water-associated features, after studying the global water status between 1990 and 2025. Moreover, Gleick, et al (2002) presented an overview on various global water resource records that included water demand in several sectors and water supply from several sources. Margolis (1995) investigated about the future of water considering a typical business environment on the basis of anticipated economic growth evaluated with respect to “gross national product (GNP) growth and its past correlation with water demands” (Margolis, 1995). Further, Seckler et al (1998) generated possible situations of water supply and its demand to 2025, recognized nations that are likely to encounter grave water scarcity in the coming 25 years. They also summarized few possible remedies to discard water shortages along with the betterment of irrigation water usage efficiency as well as expansion of its supply. A few goals of an ongoing study in global freshwater measurement are:
1. Improving the long-term estimation by considering the changing global climatic conditions
2. Improving the ways of forecasting inter-annual and seasonal climatic variance
3. Development of the relation between biochemical and hydrological functions, and food production
For its sustainable use, it is impossible to withdraw water from reservoirs and other sources at a faster rate that it is refilled via the natural hydrologic cycle. It is important to draw water at a rate that allows water-table level to stay stable at all times. Apart from global water modelling and measurement techniques, other research studies and methods contributing to the development and management of water include
Field water management
Integrated basin management
System analysis methods
Crop water modelling
Evidently, ample information exists for both regional as well as global water development, and maintenance assessment. But the growing complexity of the physical facets of water resource development produce other forms of social, political, legal, and economical explanations. Of late, additional complications have been introduced by issues of environmental concerns, protection and improvement matters. Moreover, multiple objectives of water development projects are usually incompatible or differing, and water allocation disputes among downstream and upstream users and among various sectors have materialized. In addition, advanced problem-solving technologies like operations research, system analysis, and decision support systems (DSS) have been developed and implemented for tackling such increasing complexities encountered in the approaches to water resource development. Still there is immediate need and necessity to conduct additional research in order to conceive and measure mankind’s reliance on water today and in the coming years. Policy analysis needs to involve integration of sections of data form a coherent analytical model that supports the merging of national and international causes for policy-related research of global / regional water resource. The beauty of ‘sustainable development’ is that one must use natural resources in ways that would not restrict their availability to the generations to come.
References:
Alcamo, J. P., Kaspar, D. J and Siebert, S., 1998. Global change and global scenarios of water use and availability: An application of water GAP 1.0. Kassel. Germany: Center for Environmental System Research (CESR), University of Kassel.
Asante, K., 2000. Approaches to continental scale river flow routing. Ph.D. University of Texas, Austin, U.S.A.
Gleick, P. H., Burns, W. C. G., Chalecki, E. L., Cohen, M., Cushing, K. K., Mann, A., Reyes, R., Wolff, G. H. and A. K. Wong., 2002. The world's water 2002–2003. The biennial report on freshwater resources. Washington, D.C.: Island Press.
Lohmann, D., Raschke, E., Nijssen, B. and Lettenmaier, D. P., 1998. Regional scale hydrology: 1. Formulation of VIC-2L Model coupled to a routing model. Hydrological Sciences Journal, 43 (1), pp. 131–141.
Margat, J., 1995. Water use in the world: Present and future. Contribution to the IHP Project M-1-3, International Hydrologic Programme, UNESCO.
Margolis, R., Raskin, P. and Hansen, E. 1995. Water and sustainability. Polestar Series Report No. 4. Boston: Stockholm Environment Institute.
Miller, J. R., Russell, G. L. and Caliri. G. 1994. Continental-scale river flow in climate models. Journal of Climate. 7, pp. 914–928.
Seckler, D., Amarasinghe, U., Molden, D., Rhadika, de S. and Barker, R. 1998. World water demand and supply, 1990 to 2025: Scenarios and issues. Research Report No. 19. Colombo, Sri Lanka: International Water Management Institute.
Vorosmarty, C. J., Fekete, B. and Tucker, B. A. 1996. River discharge database, version1.0 (RivDIS v1.0) Volumes 0–6. A contribution to IHP-V Theme 1, Technical Documents in Hydrology Series, UNESCO, Paris. <Http://www.rivdis.sr.unh.edu>.
