Water – the Bangalore story
It is a strange place to have placed four towers and have started a city but perhaps Magadi Kempegowda was not thinking of water when he had his grand dream. The city now has outgrown those four towers and the one small stream which was the only part of a running water landscape is now desecrated beyond measure and called the Vishabhavati (the poison river) from the original Vrishbhavati (that which originates from the mouth of a bull) .
As early as the 1850’s the British were complaining about the water and sanitation systems. It also did not help matters that sewage was being left into the very source from where water was being drawn. Both Ulsoor and Dharmambudhi Lake being the source and the sink.
In a pioneering effort of its kind, most probably aided by the fact that this was city not near a perennial water source and there was always a sense of shortage, the city started to search for water from far. Hessarghatta on the Arkavathy reservoir 24 km away was first developed as a storage dam. Steam engines were used to pump water into the city and when electricity came that then replaced the steam engines. In each case Bangalore was a pioneer in the use of steam and electricity to pump water to itself. Hessarghatta was found short to slake the cities thirst and Thippagondanahally on the junction of the Kumudvathi and Arkavathy came into being as a new reservoir in addition to the Arkavathy in the mid 30’s. The city continued to grow and in the 1970’s the Cauvery was tapped at Torekadinahalli, pumped to a distance of 95 kilometres and 300 metres high to quench the city’s thirst. This was a remarkable engineering feat by a remarkable institution the Bangalore Water Supply and Sewerage Board- BWSSB – the first exclusive city level water and sanitation utility created in India. Stages 1, 2, 3 and 4 and phases 1 and 2 of stage 4 have kicked in and one of the costliest water in Asia comes after being pumped in three stages into the city. Alas the limit to drawal also has been reached and there is no more water for the city unless there is a redrawing of the water requirement between the irrigation and the urban sector in the Cauvery basin part of Karnataka.
In the meantime the city found out an uncomfortable truth, not all of it was in the Cauvery basin. In fact 2/3rds of it was outside the basin and in a river called the Dakshina Pinakini or the Ponnaiyar so that part was not entitled to water from the Cauvery basin or so said the tribunal.
In true government style a committee was formed to find out how the growing needs of the economic and domestic demand of the city could be met. Proposals include getting water from the Hemavathi, the Sharavathy as well as the west flowing rivers. These of course are huge projects involving lots of money and energy, something which should get the construction lobby salivating.
In the meantime there are practical proposals such as rooftop rainwater harvesting, the rejuvenation of the remaining lakes of the city, the recharging and the management of the groundwater in the city and most importantly the treatment and reuse of waste-water which show tremendous opportunities.
While the city gets 1400 million litres of piped water supply, the equivalent of 3000 million litres per day falls as rain on it. The total volume of wastewater available for reuse is 1100 million litres and the amount of groundwater that can be drawn sustainably is close to 600 million litres per day provided it is adequately recharged.
Do the math then
Average demand 200 Litres per capita per day
Total; available water
From Cauvery 1400 million litres per day
From groundwater 600 million litres per day
From recycled waste-water 1100 million litres per day
From rainwater 600 million litres per day ( 20 % rain harvested)
Total 3700 million litres per day
Good enough for a population of 18.50 million
…and if we get demand efficiency right and demand down to 100 litres per dapita per day
37 million people of Bangalore can be served ( current population 9 million)
Unfortunately the institution in charge of water supply is not completely geared to undertake a water management approach. It has no skill set for example in lake management or in hydro-geology.
If institutional capacities are built up, if there is a strong vision and an accountable authority created Bangalore in its pioneering way can overcome its water shortage problems. Else it will be forever condemned to become dependent on a tanker economy. The choice is ours and the time is now.