World Water Day 2024: Alternative methods to conserve water

In India, as raw water is mainly sourced from groundwater, several cities and municipal corporations are facing a big gap in the demand and supply of water due to the overexploitation of groundwater reserves.

Water is one of the most precious natural resources in the world. Yet, the world is moving towards an inevitable water crisis in many geographies globally. As governments seek to conserve water, the focus is on determining the water usage of diverse industries to discover how and where water consumption can be minimised. 

‍Water-intensive Construction

In the overall context of water consumption, the construction sector ranks as one of the most water-intensive industries in the world. For example, every square metre of wall construction needs, on average, 350 litres of water. Given this background, buildings and other structural projects account for more than 10% of the total water consumption. 

In India, as raw water is mainly sourced from groundwater, several cities and municipal corporations are facing a big gap in the demand and supply of water due to the overexploitation of groundwater reserves. Typically, the maximum use of water occurs during the preparation of sand and cement mortar as well as in the curing of walls, before and after plastering.

Decoding Bengaluru’s Severe Water Crisis

More than two and a half centuries ago, American statesman Benjamin Franklin asserted: “When the well is dry, we know the worth of water.” In 2024, his statement resonates strongly with every resident from Karnataka’s capital city, Bengaluru, which is confronting its most severe water crisis in decades. Considering its population of more than 14 million people, the tech city has a minimum requirement of two billion litres of water per day. Of this, more than 70% is sourced from the river Cauvery. The balance is met from groundwater drawn through bore wells. 

However, a weak monsoon in 2023 led to the depletion of groundwater levels. To overcome this, deeper bore wells are being dug. Nonetheless, the city is facing a daily shortfall of 200 million litres of water. A recent report from the Indian Institute of Science reveals that Bengaluru’s water spread has dropped drastically to 696 hectares in 2023 from 2,324 hectares in 1973. Its water surface is said to have shrunk sharply due to widespread construction and concretization over the past 50 years. The major decline in water surface area has also affected Bengaluru’s groundwater recharge capability. 

In this context, it’s important to note that traditional methods of construction exacerbate the water crisis. Whether it is buildings, schools, hospitals or warehouses, all concrete structures need a minimal amount of water during construction. While some may advocate a ban on construction, this is not a viable solution for a country that is undergoing a development drive during the past decade. 

Multiple Benefits of Pre-Engineered Building Construction

Instead, a more practical approach is necessary that strikes a delicate balance between development needs and environmental concerns. In this scenario, the Pre-Engineered Building construction industry stands as a bright beacon of hope, with its more sustainable practices supported by a substantially lower rate of water consumption. 

As PEB construction (also termed dry construction) needs less time, water requirement for cleaning, mixing concrete and other activities is reduced significantly. Compared to conventional construction, the other benefits of PEB comprise greater control over construction time, cost-effectiveness, better quality control, higher worker safety and, thereby, greater labour productivity. For example, it permits 30% to 50% faster time in construction, unlike conventional or onsite construction. 

Thanks to the integrated processes in PEB, such as modular construction, it avoids subcontracting costs arising from more onsite labour. PEB also curb greenhouse gas emissions while reducing energy and resource scarcity, besides ensuring less damage to human and ecosystem well-being.

Furthermore, its water-efficient characteristics such as rainwater harvesting systems and low-flow plumbing fixtures curb consumption and help in rainwater utilization. In Bengaluru and other water-scarce cities, rainwater harvesting is indispensable to mitigate water-related worries. 

Conversely, traditional construction methods seem increasingly unsustainable because of the amount of water wasted. The wasteful practices include hosing down surfaces and using open systems to supply water.

Rationale for Promoting Dry Construction

PEB structures apart, other forms of dry construction also require much less water, unlike the wet method. As the name indicates, dry construction needs no water at the site since poured cement or concrete is not required. Dry construction uses Insulated Panels or Single Skin Sheet walls and Steel frameworks that can be assembled quickly onsite, without using a single drop of water.

Keeping in mind the severe water scarcity in multiple regions, the construction industry must adopt sustainable techniques to conserve water and other scarce resources while developing projects. Herein, since PEB and other dry techniques need much less water, they also ensure effective water management during construction. 

As World Water Day is commemorated, it’s time that all stakeholders, including individuals, pledge to use dry construction methods while also inspiring everybody else to embrace water-saving practices. The future of upcoming generations and the planet depends on our universal commitment. 

Source: Financial Express‍