According to a senior BWSSB official, “Builders were giving ‘construction as the reason while seeking permission to dig borewells. In some places, the groundwater is as good as drinking water. He further stated that, we can’t let freshwater be wasted on construction. So, from now on, builders should only use treated water.
To improve the groundwater levels in the city, the Karnataka Groundwater Authority (KGA)-appointed committee has decided to refuse permission to use borewell water for building construction.
According to a senior BWSSB official, Builders were giving ‘construction as the reason while seeking permission to dig borewells. In some places, the groundwater is as good as drinking water. He further stated that, we can’t let freshwater be wasted on construction. So, from now on, builders should only use treated water.
Disproportionate supply and demand of Groundwater over the years
In the 1960s, the number of tanks and lakes was 280 in Bangalore, which dwindled to less than 80 by 1993. While the water needs of the city were met by these tanks and lakes, the number of lakes kept coming down due to development and encroachment and hence since 1970s, the scheme to pump water from the Cauvery river by raising the water up by 500 metres was introduced. Way back in 2001, the demand for water was 750 million litres per day, while the actual supply was only 570 million litres per day and the per capita usage was about 105 litres per day as against the national standard of 150 litres per day. These figures must have gone up by leaps and bounds in the last decade because of the sporadic development activities and increasing encroachment of land by land sharks. Of the 280-285 lakes that Bangalore once had, 7 cannot be traced, 7 are reduced to small pools of water, 18 have been unauthorisedly encroached by slums and private parties, 14 have dried up and are leased out by the Government and 28 lakes have been used by the BDA (Bangalore Development Authority to distribute sites and build extensions for residential areas. Even the remaining lakes are in fairly advanced state of deterioration.
According to waterportal.org, Bangalore, with annual rainfall of 900 mm (3.0 ft) with three different rainy seasons covering nine months of the year. June to October is the rainy season accounting for 64% of the total annual rainfall in the S-W monsoon period and 324 mm (1.1 ft) during the N–E monsoons (November – December.). It has a salubrious climate with an annual mean temperature of 24 °C (75.2 °F)with extremes ranging from 37 °C (98.6 °F) to 15 °C (59.0 °F). The streams between ridges and valleys have been dammed at suitable locations creating a cascade of reservoirs in each of the three valley systems. Each lake stores rainwater from its catchments with excess flows spilling downstream into the next lake in the cascade. The storm water runs off through drains only. These drains often carry sewage in it, which results in the lakes getting polluted. Many lakes have reportedly springs at the bottom of the lakes, some of which are stated to be choked due to silt, which also feed the lakes.
Officials unable to meet demand
According to media reports, Officials admit that city authorities, unprepared for the speed of the city’s tech boom, did not adequately plan for Bengaluru’s growing water needs.
The size of the city has more than tripled in just over a decade to 800 square km (198,000 acres) – nearly half the size of London – by swallowing dozens of settlements and villages. Bengaluru’s population has more than doubled to about 12 million since 2001 and is predicted to hit 20 million by 2031.
The Bangalore Water Supply and Sewerage Board (BWSSB) is the main agency that manages drinking water – but it can provide it to only about 60% of the city. Each day, the city pushes 1.4 billion litres of water through its pipes – but still falls 800 million litres short of meeting the city’s ballooning needs,
Alarming time for groundwater in Bangalore
Three months after a BBC report declared that Bengaluru will be one among 11 cities in the world to reach Day Zero; a government report also stated that the city will lose its groundwater by 2020. In fact, not only Bengaluru, 20 other major cities of the country, including the national capital New Delhi and Hyderabad is in the Niti Aayog’s list to reach zero groundwater levels, affecting access for 100 million people. The list is part of ‘Composite Water Management Index: A Tool for Water Management 2017’ by Niti Aayog.
Bengaluru features in the list of cities which are in the risk of losing groundwater despite Karnataka being the fourth best state for water resource management among non-Himalayan states in the 2017 list.
Special committee formed for stopping Groundwater for construction banned in city
The special committee constituted by KGA –which includes the officials from BBMP, Police department, BESCOM, BWSSB, groundwater authority and KSPCB- has decided to take legal action against the property owner and the borewell digging agency if they are found to be drilling illegal borewells. The move is to curb rampant digging of borewells within the BBMP limits.
The committee has also asked the public to contact one of the civic agencies (represented in the committee) if they notice illegal digging of borewells in their neighbourhood.