How Cauvery came to Bangalore

When Indian attained Independence, the Civil and Military Station or rather Cantonment area which was controlled by the British and the Pettah or Pete area of Bangalore came to be merged under a single entity called Bangalore City Corporation.

The State Government passed an act merging both the municipalities of the Civil and Military Station and the Pettah areas. One of the first acts of the now undivided Municipality as also the Government was to come up with a viable, fool proof and long term water supply to Bangalore.

Then, Bangalore was being supplied water from the TG Halli, Hesarghatta and several tanks and lakes. By then, the Dharmambudhi tank had already dried up and the erstwhile municipality had allotted sites to people on its tank bed. The dry tank was being used as an open ground where national leaders like Gandhi, Nehru gave speeches and exhibitions and circuses were being held.

The British had constructed Millers and Sankey tanks to supply drinking water to Bangalore. Constructed in 1882, Sankey tank then cost Rs 5,75,000. It was linked to the Miller's tank and also Dharmambudhi tank.  The Millers tank was really huge. It too was supplying drinking water and residents preferred this water to Sankey as the quality was much better.

The Government decided to go in for a more reliable source of water to Bangalore. Even as discussions were on about which source of water to tap and how, the State Government in 1958 constituted an Expert Committee to go into the issue.

The committee was also asked to study which of the following sources would be the better to tap. The sources were: 1) Arkavathy river downstream of  T.G.Halli reservoir 2) Hemavathy River c) Shimsha River and d) Cauvery River.

The committee felt it would be better to tap the Cauvery as it had better potential in meeting Bangalore’s needs. It also said the Cauvery could be depended upon for further tapping of water as against the limited capacity of the other three rivers. The Government accepted the proposal and on April 1964 granted administrative approval for bringing Cauvery to Bangalore.

This was how the Cauvery Water Supply Scheme (CWSS) commenced and the first stage was estimated to cost Rs.22 crores.

Work on the first stage commenced during 1969 and it was completed in five years. On January 24, 1974, Bangalore received its first drop of Cauvery water.

However, the first stage barely quenched the thirst of Bangaloreans and the Government then along with the BWSSB decided to go in for the second stage to augment water supply. The work on the second stage costed Rs. 65.50 crores and it was taken up and completed during 1979 to 1982.

When even the second stage failed to bridge the growing demand for water, the BWSSB decided to go in for the third stage. Work began in 1985 and it was completed in May 1993. The total cost of the third stage was Rs. 240 crores and it brought in an additional 270 MLD of Cauvery into the City’s taps.

The total water supplied to Bangalore by all the three stages put together was 540 MLD but this too proved inadequate, forcing the BWSSB to go in for another stage to get more water.

Bringing Cauvery to Bangalore from the source at TK Halli in Kanakapura is an expensive proposition. The distance is about 100 kilometres and the Cauvery has to be pumped over a gradient in three stages of 500 feet each. The cost of pumping so much is about Rs. 400 crores, which forms a substantial chunk of the water board’s finances.

Today, the State cannot draw any more water from the Cauvery to supply water to Bangalore, It has to look at alternatives and there are plenty. Apart from tapping fresh sources, water conservation techniques such as rain water harvesting, recharging ground water, recycling waste water, segregating water for domestic and non-domestic uses, plugging leakages, modernizing the water supply and drainage system would go a long way in ensuring better water supply.   

Sacrificing power for water

Bangalore has always been a city plagued by water shortage. Though the city generally receives abundant rains and the rainy season is fairly extended, there is practically no scientific large scale retention of water.

Bangalore is also one of the few cities that has two clear cut rainy seasons-the primary of south west monsoon from June to September and the north east or secondary monsoon from November to December. The average rainfall in Bangalore is 859 mm.

Besides, the summers-March-April and May-are generally moderated by fairly frequent thunderstorms and intermittent rains. The heaviest rainfall recorded in a 24-hour period is 179 millimetres (7.0 in) on October, 1997.

Yet, these flattering statistics do not mean much as water supply has always been a problem in and to Bangalore. For decades, Bangalore has not been able to completely meet the water needs of its residents.

However, this year the water crisis is likely to be more pronounced. The Cauvery verdict restricts the amount of water that the State can draw from Cauvery for providing drinking water to Bangalore. Moreover, tanks, lakes and other water bodies have run dry and the water availability in borewells have depleted.

Bangalore today needs  600 cusecs of water per day or the total water supply per day is put at 950 million litres per day. The per capita water supply is 147 litres per day.

Much of Bangalore’s water needs is met from the Cauvery. Earlier, TG Halli added to the water supply but today it adds to the water woes as it is almost dry.  
Supposing that the monsoon sets in on time in June, Bangalore requires till May end 3.6 tmc ft water just to meet its drinking water needs. Now the question is where is Bangalore going to get its water.

Hesarghatta has completely dried, TG hall has stopped pumping and more water cannot be lifted from the Cauvery.  Hence, the State has to supply water to Bangalore from some of the reservoirs such as KRS, Hemavathi, Harangi and Kabini.

The live storage above sill level at KRS is 4.553 tmc ft, at Hemavathi it is 4.289 tmc ft,  Harangi 5.37 tmc and the live storage above sill level at Kabini is zero.
Since this limited the option of the State Government, it did the next best thing. It ordered mini hydel stations to stop generating electricity and ordered that the water held in the power stations could be used for meting Bangalore’s growing thirst for water.
Thus, we had the Minister for Energy and Bangalore Water Supply, S. Suresh Kumar, directing the Energy department and the Cauvery Neeravari Nigam to stop power generation at four mini hydel plants.
Following the directive,  power generation has stopped at Shiva Balancing Reservoir (SBR), which had reached 3.34 feet (minus 40 inches) last week. Since then, Bangalore has been receiving water from the Shiva Balancing Reservoir.
The Shimsha power unit too has gone silent and its waters are being diverted to Bangalore. The two private power generating companies at Madhavamantri and Satyagala barrage too have been asked to stop power supply and instead divert water to Bangalore.
Both Madhavamantri and Satyagala together produced  0.7 MW of power were using water from the upstream of the river course.
Their practice of storing water and using it later had caused imbalance in the flow to Shiva Balance Reservoir (SBR).
Similarly, the Shiva and the Shimsha power plants used water that  would flow down to the river after power generation. These plants generated less than one per cent of the total power generated in State. However, they used nearly 50 cusecs of water which otherwise could be used for drinking water supply.
The Government has set up a vigilance committee comprising the heads of these departments as well as deputy commissioners of Mysore, Mandya and Chamarajanagar to ensure smooth flow of water along the river course and to keep a tab  on unauthorised drawing of water.
The committee has also been told to ensure that water is not used for power generation or irrigation activities for now. Thus, Bangaloreans should thanks the stars for getting exclusive water