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Watershed Management (BCV405D) BLDEACET, Vijayapur. CSM 1 Module - 2: Water Resources Systems Water Resources are sources of water that are potentially useful for humans. They can use water for a variety of purposes, including agriculture, industry, domestic use, recreation, and environmental preservation. Almost all of these uses need fresh water. Only about three percent of Earth's water is freshwater. Water is the most valuable natural resource and a crucial component of a nation's socioeconomic development. Water is used for a variety of things, including drinking, bathing, washing, irrigation, and industrial processes. Therefore, it is a necessary component of life. Water Resources are the various resources of water on Earth. About 71% of the surface of the earth is covered with water. However, the way that water is distributed on Earth appears to mean that only a small portion of the total amount of water that is present is fit for human consumption. The detailed distribution of water is shown below in the image: Water Resources in India: In India, the primary source of water is rainfall. Approximately 2.45% of the world's surface area, 4% of its water resources, and 16% of its population are all accounted for by India. About 4,000 cubic kilometres of water are available from precipitation in the entire nation each year. 1,869 cubic km are available from surface water and replenishable groundwater. Only 60% of this can be applied to good purposes. Consequently, the nation's total usable water supply is only 1,122 cubic kilometres. Types of Water Resources: Water Resources can be classified into 2 major types: 1. Surface Water Resources 2. Groundwater Resources. (Refer Module- 1)
Watershed Management (BCV405D) BLDEACET, Vijayapur. CSM 2 Integrated Water Resources Management (IWRM): It has been defined by the Technical Committee of the Global Water Partnership (GWP) as "a process which promotes the coordinated development and management of water, land and related resources, in order to maximize the resultant economic and social welfare in an equitable manner without compromising the sustainability of vital ecosystems." Integrated Water Resource management is an effective and efficient water management process, which recognizes water as an integral part of every ecosystem. Quantity and quality of available water determines its usages. It is a continuous process and not a short term approach. IWRM can be made successful by applying and adjusting management techniques depending on the given situation. Policies should be framed based on various usages of water, while giving voice to all stakeholders in water management and planning. WHY IWRM? Water is vital for human survival, health and dignity and a fundamental resource for human development. The world’s freshwater resources are under increasing pressure yet many still lack access to adequate water supply for basic needs. Growth in population, increased economic activity and improved standards of living lead to increased competition for, and conflicts over, the limited freshwater resource. Here are a few reasons why many people argue that the world faces an impending water crisis: Water resources are increasingly under pressure from population growth, economic activity and intensifying competition for the water among users; Water withdrawals have increased more than twice as fast as population growth and currently one third of the world's population live in countries that experience medium to high water stress; Pollution is further enhancing water scarcity by reducing water usability downstream; Shortcomings in the management of water, a focus on developing new sources rather than managing existing ones better and top-down sector approaches to water management result in uncoordinated development and management of the resource. More and more development means greater impacts on the environment. Current concerns about climate variability and climate change demand improved management of water resources to cope with more intense floods and droughts.
Watershed Management (BCV405D) BLDEACET, Vijayapur. CSM 3 There is growing awareness that comprehensive water resources management is needed, because: Fresh water resources are limited; Those limited fresh water resources are becoming more and more polluted, rendering them unfit for human consumption and also unfit to sustain the ecosystem; Those limited fresh water resources have to be divided amongst the competing needs and demands in a society Many citizens do not as yet have access to sufficient and safe fresh water resources It is increasingly realised that there is a huge potential to increase crop production and achieve food security through more efficient use of rainfall through improved soil and water conservation and harvesting techniques Structures to control water (such as dams and dikes) may often have undesirable consequences on the environment There is an intimate relationship between groundwater and surface water, between coastal water and fresh water, etc. Regulating one system and not the others may not achieve the desired results. Hence, engineering, economic, social, ecological and legal aspects need to be considered, as well as quantitative and qualitative aspects, and supply and demand. Moreover, also the ‘management cycle’ (planning, monitoring, operation and maintenance, etc.) needs to be consistent. IWRM system is not a Onetime solution; it’s a process, designed to meet the following three main objectives: 1. To make freshwater resource available as far as possible. 2. Water should be available to all irrespective of their social and economic status. 3. Water should be protected for sustainable environmental development. Three key policy Principles are known as the three 'E's as defined by Postel (1992) i.e. Social Equity, Economic Efficiency and Environmental Sustainability. Social equity: means ensuring equal access for all users (particularly marginalised and poorer user groups) to an adequate quantity and quality of water necessary to sustain human wellbeing. The right of all users to the benefits gained from the use of water also needs to be considered when making water allocations. Benefits may include enjoyment of
Watershed Management (BCV405D) BLDEACET, Vijayapur. CSM 4 resources through recreational use or the financial benefits generated from the use of water for economic purposes. Water is a basic need. No human being can live without a basic volume of fresh water of sufficient quality. Humans have a basic human right of access to water resources Economic Efficiency: means bringing the greatest benefit to the greatest number of users possible with the available financial and water resources. This requires that the most economically efficient option is selected. The economic value is not only about price - it should consider current and future social and environmental costs and benefits. Water is a scarce resource. It should be used efficiently; therefore, institutional arrangements should be such that cost recovery of the water services should be attained. Ecological Sustainability: requires that aquatic ecosystems are acknowledged as users and that adequate allocation is made to sustain their natural functioning. Achieving this criterion also requires that land uses and developments that negatively impact these systems are avoided or limited. Water resources can only persist in a natural environment capable of regenerating (fresh) water of sufficient quality. Only sustainable water use can be allowed such that future generations will be able to use it in similar ways as the present generation. Implementation of IWRM: IWRM aims to create sustainable water security within the present constraints and to improve the conditions in the catchment basin. Some important conditions for implementing IWRM are presented below: Political Will and commitment: Political Will at all levels can help unite all stakeholders and move the process forward. It is especially needed if the resulting plan or arrangement would create or require changes in legal and institutional structures, or if controversies and conflicts among stakeholders exist. Access to actors outside the water box is essential to move political will, gain sectorial support and ease public pressure for IWRM implementation. Basin management plan and clear vision: Water resources development coordinated among various sectors and users is facilitated by the preparation of a master plan that reflects the individual sector plans and offers the most effective and efficient utilization of the resource. Participation and coordination mechanisms, fostering information-sharing and