Harvesting raindrops to check groundwater depletion

Groundwater accounts for 99% of freshwater in the world but rapid depletion of water level in accessible sources has set off the alarm bell on availability of freshwater in future. The Master Plan for Artificial Recharge to Groundwater in India, 2020 prepared by the Central Ground Water Board (CGWB) reveals that the water stress is being felt at different parts of India owing to the increasing demand resulting from the population explosion. It flags the concern that share of groundwater has far exceeded the natural recharge in many parts of the country to meet the demand. Of 167 groundwater wells analyzed by CWGB in Assam, 55% wells registered fall in groundwater level over a decade between 2011 to 2020. Compared to overall groundwater situation in the country this is quite alarming. Nationally, of the 14,275 wells analyzed by CGWB, 30 % of the wells registered declined in groundwater level while 70% well registered rise in water level. The CGWB plan highlights the paradox of water availability for domestic use, animal and crop production in northeast region being negligible not only during lean period but also during rainy season despite the region receiving the highest rainfall in the country. The Master Plan attributes the water scarcity in the hilltops of region to dwindling discharge in many natural water sources in the hills and envisages rainwater harvesting as the solution to address the problem. It estimates that 3.2 million cubic meters of rooftop rainwater can be harvested in 97,882 schools in the region while 3264 health centres in the region together have rooftop rainwater harvesting potential of 26,058 cubic meters. Total cost of putting in place these rooftop water harvesting structures in these schools and health centres is estimated at Rs 1683 crores. Considering the huge benefits of water harvesting and addressing water scarcity problem, the expenditure not only justified but also warrants speedy implementation of the plan for sustainable use of available groundwater. The Master Plan envisages construction of about1.42 crore rainwater harvesting and artificial recharge structures in the country to harvest 185 billion cubic metres of monsoon rainfall but water being a state subject, its implementation depends on priority attached by State Governments. The constitution of the Central Ground Water Authority (CGWA) under Section 3(3) of the Environment (Protection) Act, 1986 at the directive of the Supreme Court for the purpose of regulation and control of ground water development and management in the country marked an important phase in ground water conservation initiatives in the country. The CGWA regulates ground water withdrawal by industries, infrastructure and mining projects in the country and framed the guidelines which include rainwater harvesting as one of the provisions for issuing No Objection Certificate. With connectivity projects pushed by the Central government to transform the Northeast from a landlocked region to a well-connected region, the region is poised to witness industry expansion, and which will lead to increase in water demand for industrial purpose. States in the region and the CGWA taking note of the transformation in the region and strictly enforcing the rainwater harvesting as required by the norms is critical to check overexploitation of the available groundwater. About 20 million irrigation wells drawing underground water for agricultural activities in the country has resulted in over-exploitation and depletion of water table in many areas of the country which is a cause of great concern. In urban areas like Guwahati, problem of depletion of the groundwater table on account of digging of borewells in multi-storied housing complexes as well as individual houses has been aggravated by delay in execution of piped water supply projects in the capital city. The residents grappling with water scarcity for decades despite the mighty Brahmaputra flowing by the city paint a gloomy picture of administrative inefficiency and poor project management. Rising number of water tankers which supply water in areas of the city where wells have dried up or water table has fallen beyond affordable cost of digging a borewell speak volume about the impending crisis on account of further delay in execution of the water supply projects. The Ministry of Housing and Urban Affairs circulated the Model Building Bye Laws, 2016, for guidance of the States and Union Territories under which provision of rainwater harvesting is applicable to all residential plot above 100 sq. meters but lack of transparency on implementation of the provision keeps alive the apprehension of overexploitation of groundwater. The World Water Day observed today on the theme 'Groundwater: Making the Invisible Visible' has great significance for the north-eastern region. It reminds all stakeholders about the urgency to build awareness about the importance of harnessing rainwater for sustainable use of groundwater. State Governments roping in panchayats, autonomous district councils, NGOs, community leaders, cultural institutions, celebrities, educational institutions to spread the awareness is the need of the hour.