Water scarcity involves water stress, water shortage or deficits, and water crisis. This may be due to both natural and human factors. But, many reports suggest that the scarcity is more due to the human factor – such as industrialisation, irrigation, domestic use, etc. Water scarcity is the lack of sufficient available water resources to meet the demands of water usage within a region. It affects every continent and around 2.8 billion people around the world, at least one month out of every year. More than 1.2 billion people lack access to clean drinking water.
Agriculture, the largest consumer
Currently, agriculture is the largest consumer of water, accounting for 84 per cent of total available water, followed by industry accounting for 12 per cent, and the domestic sector which accounts for four per cent. Some experts have argued that India, which currently uses two to four times the quantity of water to produce one unit of major food crops as compared to other major agricultural countries like China, Brazil and the United States, can save half of that water, if it attains the water use efficiency of those countries.
India accounts for about 17 per cent of the world’s population, but only four per cent of the world fresh water resources. More than 80 per cent of the water needs of the country is met by exploiting ground water. This has accelerated the depletion of the water table, and led to an unprecedented water shortage. Of the total cultivable area, about 60% is rain-fed and remaining 40% is dependent on irrigation. Undoubtedly, the irrigation potential created from various irrigation schemes has recorded massive increase, representing about 81% of India’s ultimate irrigation potential; thus, there is now only limited scope for further expansion of irrigation infrastructure on a large scale. Nevertheless, irrigation is predicted to remain the dominant user of water in the years to come.
Numerous regions in the country are chronically faced with acute water stress. These include districts of South and North in interior Karnataka; Rayalseema in Andhra Pradesh; Vidarbha and Marathwada in Maharashtra; western Rajasthan and Bundelkhand region of Uttar Pradesh and Madhya Pradesh. Low and erratic rainfall for consecutive years in these districts have rendered water-harvesting structures devoid of water, and the conservation measures almost unviable. The water storage in reservoirs have depleted, leading to scarcity of drinking water. The moisture index in majority of these districts is in the range of -85 to -50%, denoting that natural precipitation is highly inadequate to support arable cropping. Neither normal agricultural practices, nor the contingency measures may help the farmers. Experts have called for focusing specific attention on linking these districts with some perennial source of water.
The rain-fed groundwater reservoirs are over-exploited due to high demand and shortage of supply through rainfall. A significant fraction of the rainfall flows into the ocean without being arrested by any aquifers or water bodies. The potential retrieval of this water to compensate for the scarcity of groundwater in the region can be addressed through rainwater harvesting programmes, either through lakes or shallow aquifers, or revival of traditional water conservation bodies.
The Meghalaya approach to rainwater management
Meghalaya, being the main beneficiary of the Southwest monsoons, receives very high rainfall, higher than most parts of the country. The rainfall varies in the state, from more than 12000mm in the southern slopes, to close to 2000mm in the northern slopes. However, the rainfall is only for 6-8 months in a year, leaving the dry months with lots of water scarcity problems, since there is 90% runoff. And due to the distinct topographical and geo-morphological conditions of the state, there is high surface runoff to the neighbouring plains. In total, rainwater discharge from 11,667 sq km of catchment area in the state drains into the Brahmaputra Basin, and from the rest 10,650 sq km, into the Barak Basin. It is anticipated that the state requires about 15 BCM (Billion Cubic Metres) of stored water annually for meeting the requirements for drinking water, irrigation and other livelihood generating activities such as fisheries.
With all the factors, including the uncertainty of rainfall, the water availability situation in Meghalaya is grim. Increasing water availability throughout the year in the state by providing storage facilities through rainwater harvesting have been given importance, and various projects have already been taken up by the state government under its Integrated Basin Development and Livelihood Programme (IBDLP), which has been implemented in a mission mode by the Meghalaya Basin Development Authority (MBDA), Government of Meghalaya. As a start, the government has initiated programmes like jalkunds, Multi-purpose Reservoirs (MRs) and roof-top rain water harvesting as tools to implement rainwater harvesting in the state.
Partnership with India Water Foundation
India Water Foundation (IWF) is a development partner of the MBDA, in managing water resources in the state. Inputs from IWF have helped in the adoption of Integrated Basin Development and Livelihood Programme by the MBDA, which also looks after water and agriculture sectors in tandem with respective government departments.
As a result, the trends in water conservation and rainwater harvesting are gradually undergoing change for the better because mechanisms are in place in the form of jalkunds (small water reservoirs), MRs and roof-top rainwater harvesting, to provide water during the lean period.
The Jalkund Programme
Jalkunds are small water harvesting structures that supplement the crop water requirement during the dry season when numerous types of crops may be grown. It also helps expand the irrigation coverage, especially in areas which are on the fringes of existing command areas. The Jalkund Programme is restricted to a total command area of 10 ha (hectares). It has become a boon especially to many small and marginal farmers in the remote parts of the state, who would otherwise not be eligible for most of the irrigation schemes.
According to broad estimates, over 600 jalkunds have been created to help create irrigation potential of 1942.46 hectare, and these schemes are being implemented through the District Water Resources Councils (DWRCs).Viewed from a broad perspective, jalkunds are small micro-rain water harvesting structures to preserve the water resource that is available abundantly during the monsoon and for utilising them during the lean periods. Initially, attention was focused on type-I jalkund structures, because this type of rain water harvesting was deemed suitable in location where there are negative spaces and the topography allows for the surface runoff/ natural drainage to be blocked by an impounding structure. The water impounded from these structures can then be conveyed by gravity to the required locations through canals or pipe.
Subsequently, only 5-10 type-II structures of jalkunds were implemented on a model basis. These structures are suitable mostly on hill tops, where the collection of rainwater is in-situ. These structures can vastly help in converting jhum cultivation areas. The target area for these structures is more localised as the storage of water is completely dependent on the rain water that falls directly from the sky. The coverage will also depend on the size of the pond and the crops planted.
The avowed objective of these jalkunds is to achieve the goal of providing access to irrigation water to every farmer in the state by the end of the 12th five-year plan. In view of various agro-climatic zones in the state, different types of jalkunds are being implemented based on the need assessment of the farmer, in consultation with the DWRCs.
Multipurpose Reservoirs are water resources structures that will cater to the different water needs of the community such as drinking and domestic water, irrigation, fisheries, livestock and micro-hydel, etc., wherever feasible.
Roof-top rain water harvesting
Realising the importance of having adequate and clean water supply in Health Centers across the state, the Government of Meghalaya is proposing to construct rain water harvesting structures in Primary Health Centres and Community Health Centres located all over the state. The water will be stored in 50,000-1,00,000 litres tanks, which will supplement the daily domestic water requirements. It is anticipated that this programme will cover schools and colleges, institutions, offices, etc., in due course of time.
India is already a water-stressed country, moving towards becoming water scarce. Water scarcity has many negative impacts on the environment, including on lakes, rivers, wetlands, and other fresh water resources. This Meghalaya approach can prove to be a milestone in resolving the country’s water crisis.