GK: Is Bengaluru about to run dry? (ENVIRONMENT)

Earlier this month, a BBC report listed 11 world cities that were “most likely to run out of drinking water”, and put Bengaluru at number 2, behind only São Paulo, Brazil. The report mentioned the acute shortage of water in Cape Town in South Africa, where people are now being rationed 50 litres daily, and which many fear could become the first major city to run dry in the modern era. Other cities on the list of the most vulnerable were Beijing, Cairo, Jakarta, Moscow, Istanbul, Mexico City, London, Tokyo and Miami.

The report noted that more than half of Bengaluru’s drinking water is wasted due to “antiquated plumbing”, 85% of the city’s lakes “had water that could only be used for irrigation and industrial cooling”, and “not a single lake had suitable water for drinking or bathing”.

The Supreme Court has recently allocated a larger share of Cauvery water for Bengaluru’s nearly 10 million people, but there is little doubt that the city’s water resources must be managed more efficiently.

Bengaluru originally had multiple sources of water supply in the form of over 200 lakes, abundant groundwater, and supplies from reservoirs and tanks in the Arkavathi river basin — the Hesaraghatta Lake in the north and the Thippagondanahalli Reservoir in the west. These sources are all but dead now due to the depletion of catchment areas in the wake of uncontrolled infrastructure expansion. This makes Bengaluru critically dependent on the Cauvery — some 100 km away, and now the principal source of the city’s drinking water — and the monsoon. 

The proliferation of borewells, especially in the core city areas, has led to a massive depletion of groundwater. Only about 70 of the 272 lakes in and around the city from four decades ago survive. The government has reclaimed dozens of lakes for bus stands, stadiums, and housing complexes, and real estate firms have been the major beneficiaries of land allotment on lakeshores. Garbage and sewage have poisoned lakes, and the concretisation of catchment areas has choked inlet channels.

Bengaluru has some cushion because the Cauvery is perennial, and the city gets a decent amount of rainfall every year, which can be utilised to meet drinking water needs and recharge the groundwater table.

Great responsibility lies with the citizens of Bengaluru to use water judiciously and to save water. Rampant exploitation of groundwater should be avoided and rainwater harvesting should be undertaken in a way to replenish the groundwater.