Shun grandiose solutions to manage water 

The reality of water crisis cannot be ignored. Water scarcity is listed in the World Economic Forum’s Global Risks Report 2024 as one of the top-10 threats facing the world in the next decade.

With over 87 per cent of the global wetland resources being lost since 1700, NASA satellite data reveals that almost half of the earth’s 37 largest aquifers are running out too fast to be replenished and an additional 13 are declining at a faster rate. With more than 7.5 billion people on the planet, and the population projected to top 10 billion by 2050, the situation is set to get worse.

Currently, 844 million people, that is about one in nine of the planet’s population lack access to clean, affordable water within half an hour of their homes, and every year nearly 300,000 children under five, die of diarrhoea, linked to dirty water and poor sanitation. With water running out, the world may have to confront a series of associated problems — food insecurity, heat waves, deteriorating sanitation and regional conflicts over water access.

Water Crisis in India

According to the UN World Water Development Report, 2023, India is expected to face severe water scarcity by 2050. The World Bank in a report in 2023, too has reiterated the same.

A NITI Aayog report on Composite Water Management Index (CWMI) in 2019, underlined that around 820 million people in 12 major river basins of India are facing high to extreme water situation, about 163 million live without access to clean water close to their homes and about 70 per cent of India’s surface water is contaminated.

In a bid to find water, countries are turning to more unconventional sources. Wastewater is also a source of energy, nutrients and other recoverable materials, yet only 58 per cent of household wastewater is safely treated globally (UNEP data). Wastewater is often not reused due to fears about contagions, microplastics and antimicrobial drugs. But experts say with the right policies and technologies, wastewater can be given a second life.

According to a 2018 UN study there are 15,906 operational desalination plants producing around 95 million cubic metres a day of desalinated water for human use, of which 48 per cent is produced in West Asia and North Africa. About half of Saudi Arabia’s drinking water comes from it.

However, desalination requires hefty investment in piping and pumping infrastructure, while the fossil fuels normally used in the energy-intensive desalination process contribute to global warming.

Given that the atmosphere contains an estimated 13,000 cubic kilometres of water vapour, a growing number of countries are experimenting with cloud seeding, a technique in which clouds are sown with silver iodide to make them rain or snow.

Nations such as Australia, South Africa and China have invested in this technology. Fog harvesting is already happening in parts of the world. Studies confirm that at times more than 20 litres can be collected on a dense fog day for every square metre of mesh.

Steps to Ease Water Stress

Let us not ponder on expensive mega projects and engineering solutions which involve a huge carbon footprint. Laying huge pipeline networks for water supply means that yet again, we are giving more preference to infrastructure.

Looking at the current situation, a recovery-based closed loop system is the need of the hour.

All this leads to the fact that we need to promote a decentralised approach, with a key focus on water conservation, source sustainability, storage and reuse wherever possible. Unless we capture rainwater during the monsoon season, we will always run out.

Being low cost, highly decentralised empowering individuals and communities to manage their water, rainwater harvesting is one of the best ways to sustain our surface and subsoil water. In fact, rainwater harvesting has demonstrated the potential of raising food production more than increase in irrigation.

While groundwater resources and rivers have attracted sufficient attention of policymakers in India, small water bodies have slipped under their radar. Given the observation of the First Census Report on Water Bodies, 2023 that it is the ponds and tanks that have been largely encroached in the country, a rethinking on the approach towards water bodies is needed.

The key to resolving both water scarcity and flooding lies in reviving these small water bodies and increasing the capacity to store more water, given the climate experts’ prediction that there will be fewer but more intense rainy days, increasing the chances of flooding.

Rather than seeking expensive solutions to ensure water access for all, prioritizing investment in these cost-effective measures is prudent.

The writer is Associate Professor, VIT Chennai

COMMENT NOW