Context: Recently, a new hydrology model-based study titled as ‘Detection and Socio-economic Attribution of Groundwater Depletion in India’ has proven a clear correlation between urbanisation and a decline in groundwater reserves in Indian states of Punjab and Haryana, Uttar Pradesh, West Bengal, Chhattisgarh and Kerala.

Availability of Water in India

• India hosts around 18% of the global population, faces a severe water crisis despite having only 4% of the world’s freshwater resources. 

• Groundwater, which supports over 60% of irrigated agriculture and around 85% of domestic water supply in rural areas, is depleting at an alarming rate.

• The belief that the country receives sufficient rainfall to fulfil the needs of its large population does not carry much weight.

• Only around 8% of the rainwater received is harvested, and more than 90% of the groundwater (which should have been recharged by rainwater) is claimed by agricultural practices — and is misused.

Ground Water Extraction: A Global Crisis

• The first case of land subsidence due to groundwater extraction was reported in California, USA, in the early 1990s, where families were evacuated after certain regions recorded subsidence of up to 150 m, over 50 years.

• The San Joaquin Valley of California, land continues to sink by 0.3 m per year due to excessive pumping of groundwater for a commercial orchard, which has caused permanent subsidence and landslides in the area.

• In Southeast Asia, the rapid growth of megacities has led to a pressing design problem that many governments are only just starting to address. Jakarta is considered the world’s fastest sinking city. With 40% of the city already below sea level, it is predicted that by 2050, some 95% of North Jakarta will be underwater.

• Bangkok in Thailand and Ho Chi Minh City in Vietnam are also sinking, with subsidence rates of up to 2 cm and 5 cm per year, respectively.

Key Findings of the Report

• The study identifies Punjab, Haryana, Uttar Pradesh, West Bengal, and Chhattisgarh as the most affected states. These regions have experienced a substantial decline in groundwater levels over the past two decades. 

• The northern and northwestern hotspots, particularly Punjab and Haryana, have lost approximately 64.6 billion cubic metres of groundwater.

• Between 2004 and 2020, the state experienced a 17% decline in net annual groundwater availability — the highest among the five hotspots. Groundwater demand for irrigation dropped by 36% during this period, while domestic and industrial uses increased by 34%.

Case Study Related To Rural Areas of Punjab and Haryana

• After the high agricultural advancement and practices, the two states saw tremendous groundwater dependency for irrigation.

• Although the two states lie in an arid to semi-arid zone which sees moderate precipitation in the monsoon months, this is not enough to recharge aquifers to their previous level, hence causing land deformation, which is mostly witnessing tensional, compressional and shear cracks with vertical, horizontal and diagonal orientations in nature.

Causes of Groundwater Depletion

• Urbanisation: Rapid urbanisation has led to increased water demand for domestic and industrial use. In areas like Faridabad and Gurgaon in Haryana, groundwater levels have been dropping since 2012, despite minimal agricultural activity.

• Industrialisation: The growth of factories and industrial units has further strained groundwater resources. The study notes a significant increase in the number of factories in Punjab and Haryana, correlating with a drop in groundwater availability.

• Irrigation Practices: While urbanisation and industrialisation are major factors, irrigation for agriculture also plays a role in groundwater depletion.

• However, the study highlights that urban areas with minimal agriculture are still experiencing significant groundwater loss.

Implications

• The depletion of groundwater reserves has far-reaching consequences. Reduced groundwater levels can lead to decreased agricultural productivity, degraded soil quality, and long-term socio-economic challenges. 

• The study calls for immediate action to address these issues and ensure sustainable water management practices.

• Environmental Implications: Rapid decline in groundwater reserves and contributing to India’s carbon emissions.

• It has resulted in the Earth’s axis tilting nearly 80 cm to the east.

• It is linked to land subsidence, which is an irreversible process.

• Groundwater extraction has been linked to the climate crisis, and impacts the ecosystem and biodiversity.

• Socio-economic Implications: Groundwater extraction is the lowest since 2004, and came down by about 6 billion cubic metres in 2022 from 2020, causing the increased cost and adverse effects on food supply and communities.

Recommendations

• Rainwater Harvesting: Implementing rainwater harvesting systems can help recharge groundwater levels and reduce dependence on groundwater for domestic and industrial use.

• Sustainable Agriculture: Promoting precision agriculture and efficient irrigation techniques can minimise water wastage and reduce the strain on groundwater resources.

• Policy Interventions: Stronger regulations and policies are needed to manage groundwater extraction and ensure equitable distribution of water resources.

Conclusion

• The study serves as a wake-up call for policymakers, industries, and citizens alike. Ensuring sustainable water management practices is crucial to preserving groundwater reserves and securing the future of these states. 

• By addressing the root causes of groundwater depletion, India can work towards a more sustainable and water-secure future.