Approximately 21% of diseases are related to water among all diseases of the country (Snyder 2020). As per UNICEF and WHO (2012) estimates, approximately 97 million Indians do not have access to safe water. Further, the findings of the 2011 census revealed that 138 million rural households had access to safe drinking water, whereas 685–690 million people lacked access to safe drinking water. An ironic fact is that more than 41% of the rural population (out of 833 million people) of India own mobile phones but have no access to potable water which is a basic need. Only 18% of the rural population have access to treated water (Unitus Seed Fund 2014; Forbes India, 2015).
The NITI Aayog report (2018) also said that India is facing its worst water crisis in history, which is only expected to become worse as the country's water demand is projected to be twice the available supply by 2030. The report said that 600 million currently face high to extreme water shortage, with around two lakh people dying every year due to inadequate access to potable water. The increasing water shortage will also affect the gross domestic product (GDP) of the nation, with the country suffering a loss of up to 6% of GDP in 2030 (NITI Aayog 2018).
The quality of both river and groundwater is deteriorating at a rapid pace, making water scarcity more severe. Even toxic heavy metals like uranium, lead, cadmium, selenium, and so on are also reported in groundwater samples from various states (Chowdhury et al. 2016; Kumar et al. 2018, 2020; Sharma et al. 2020). This may lead to severe consequences for water resources. According to the IDSA report (2010), it has been reported that India is expected to become “water‐stressed” by 2025 and “water‐scarce” by 2050.
Further, climate change is also affecting the water security of India as rising temperature affects the Himalayan glaciers as well as altering the monsoon pattern. The combination of these two factors affects the level of river water due to the melting of glaciers and intense rainfall. Further, groundwater resources are also affected directly and indirectly by the alteration of these factors. High water temperature, changes in timing, intensity, and duration of precipitation are the significant consequences of climate change which can further affect the water quality. The alternate pattern of precipitation leads to floods and droughts, which play an important role in the degradation of water quality by adding a quantum of concentrated pollutants. As per the World Bank report (2018), climate change can affect 6% GDP of some regions due to water security, resulting in migration and conflict. As per the United Nations Convention to Combat Desertification (UNCCD), by 2030, due to climate change impacts on water scarcity, 24–700 million people may be displaced from some arid and semi‐arid places.
The achievement of water security in the future will be a very challenging task. This chapter describes in detail the current situation and future challenges regarding water security along with prospective health changes. Further, the impact of climate change on water security and health has been analyzed. The available opportunities are also discussed to manage future challenges related to water security.
1.2 Quantity of Available Water Resources in India
The annual precipitation (rainfall+snowfall) is estimated as 4000 billion cubic meters (BCM). Out of total annual precipitation, 3000 BCM falls during the monsoon season (Jun to September) (Central Water Commission 2014). Around 53.3% of total annual precipitation is lost due to evapotranspiration, which leaves a balance of 1986.5 BCM. The total annual utilizable water resources of India are 1123 BCM, which consists of 690 BCM surface water and 433 BCM of groundwater (Central Water Commission 2014). The National Commission on Integrated Water Resources Development (NCIWRD) projected that total water demand to expect 973 (low demand scenario) to 1180 BCM (high demand scenario). The water used for agriculture is the highest projected demand (70%), followed by households (23%) and industries (7%) (NCIWRD 1999). The per capita average water availability in India in the year 2001 was 1816 m3, and it is expected to reduce to 1140 m3 in 2050 (MoWR 2015). The people of the Indian state of Andhra Pradesh have the highest access to safe treated water, i.e., 36%, and it is lowest for Bihar (2%) (Forbes India 2015). The annual surface water availability of India has decreased since the year 1950 (Table 1.1).
Rivers are the primary sources of surface water in India and are considered as the lifeline of Indian cities. There are 15 large, 45 medium, and 120 minor rivers in India (Raj 2010). The rivers are either rainfed and/or based on the Himalayan glacier. The annual water potential in the major river basins of India is 1869.35 BCM, but the utilizable potential is 690 BCM. The Ganga basin has the highest utilizable potential, i.e., 250 BCM. The detailed account of surface water potential of Indian rivers is depicted in Table 1.2.
Table 1.1 Annual surface water availability of India.
Source: Govt. of India (2009).
| S. no | Year | Annual surface water availability (m3/capita/year) |
|---|---|---|
| 1 | 1951 | 5177 |
| 2 | 1991 | 2209 |
| 3 | 2001 | 1820 |
| 4 | 2025 | 1341 |
| 5 | 2050 | 1140 |
Table 1.2 Overview of surface water potential of Indian rivers.
Source: Central Water Commission, http://cwc.gov.in/water‐info.
| S. no | River basin | Catchment area (sq km) | Average water resources potential (BCM) | Utilizable surface water resources (BCM) |
|---|---|---|---|---|
| 1 | Indus (up to border) | 321 289 | 73.31 | 46 |
| 2 | (a) Ganga | 861 452 | 525.02 | 250 |
| (b) Brahmaputra | 194 413 | 537.24 | 24 | |
| (c) Barak and others | 41 723 | 48.36 | ||
| 3 | Godavari | 312 812 | 110.54 | 76.3 |
| 4 | Krishna | 268 948 | 78.12 | 58 |
| 5 | Cauvery | 81 155 | 21.36 |
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