In the hustle and bustle of urban life, the convenience of concrete floors is undeniable. From driveways and pavements to sprawling malls and residential complexes, concrete surfaces are omnipresent. However, beneath the hard, unyielding surface lies an environmental challenge that is steadily exacerbating the global water crisis: groundwater depletion.

Concrete, a composite material made from cement, water, and aggregates, is prized for its durability and versatility. However, its impervious nature prevents rainwater from percolating into the soil. Instead of soaking into the ground, water runs off concrete surfaces, often flowing into storm drains and rivers, bypassing the natural process of groundwater recharge.

Areas covered with concrete significantly affect the availability of groundwater. According to a report by the Ground Water Directorate Bangalore, the water table in parts of Bengaluru has recorded a drop of more than four meters in June compared to the same period last year. In the Nelamangala area, groundwater is now available at 50-60 meters below ground level, and in Yelahanka, it is reachable at 20-30 meters below ground level.

Experts attribute this depletion to rapid urbanization, increased impervious surfaces, and over-exploitation of groundwater. Dr T.V. Ramachandra from the Centre for Ecological Sciences at IISc emphasizes that urban spaces have been excessively concretized, and water is over-extracted, leading to dwindling groundwater levels.

The situation in Bengaluru highlights the severe impact of urbanization on groundwater. The city’s rapid growth has led to extensive construction activities, particularly in areas like Yelahanka. The proliferation of borewells for agricultural purposes and the presence of eucalyptus plantations in Nelamangala have further exacerbated groundwater depletion.

Addressing the issue of groundwater depletion requires a multifaceted approach. Urban planners and developers must prioritize sustainable practices to mitigate the impact of concrete surfaces. Implementing green infrastructure, such as permeable pavements, green roofs, and rain gardens, can significantly enhance groundwater recharge. Permeable pavements made from porous materials allow water to infiltrate through the surface, reducing runoff and promoting groundwater recharge. Green roofs covered with vegetation absorb rainwater and provide insulation, contributing to groundwater recharge. Shallow depressions planted with native vegetation capture and filter runoff, allowing it to seep into the ground, known as rain gardens.

Reforestation and the creation of urban green spaces are vital. Trees and plants increase soil permeability, facilitating water infiltration. Community awareness and participation in water conservation efforts are essential. Rainwater harvesting and the recharge of water tables should be mandatory, even in rural areas.

The Karnataka Groundwater Act of 2011 mandates the registration of borewells, but the implementation of these rules needs to be stricter. Dr Nagaraja suggests that authorities should impose penalties on defaulters and ensure compliance.

Concrete floors offer convenience and durability, but their environmental impact cannot be overlooked. The impervious nature of concrete surfaces significantly contributes to groundwater depletion, posing a threat to water security. Sustainable urban planning, incorporating green infrastructure and reforestation, is crucial to mitigating this impact. By prioritizing groundwater recharge and conservation, we can pave the way for a more water-secure future.

The writer is an environment enthusiast and an animal welfare activist, and is the Founder of Kaloms Ideas Welfare Foundation. She is also a chartered accountant.