Where our rivers begin -Water literacy for urban BangaloreJune 18, 2011
Those who do not learn from history are condemned to repeat it – George Santayana
For the people interested in water supply to Bangalore a must visit is the Channakesava Hills abutting the Nandi hills and part of the range. It is here in a small pond that the Arkavathy river is famously said to originate. It moves down the hill in the form of a spring and enters the first of the man-made reservoirs, called ‘tanks’, the Chikkarayyappanhalli Kere. From thence begins the journey of this tributary to the Cauvery. Passing through a series of tanks built to hold its water for irrigation it comes to the large ‘Nagarakere’ at Dodballapur. The entire drinking water for the town of population 100,000 used to come from this large tank. Moving further on the river comes to the almost 7 sq.km. large Hessarghatta tank. In 1894 this tank was enlarged and became the first external source of water supply to the city of Bangalore.
The Arkavathy moves further on and where the Kumudvathy merges with is the second large reservoir built for Bangalore city’s water in 1934. The Thippagondanhally reservoir so large that when full it could supply 135 million litres of water daily to Bangalore.
Further down the Arkavathy is joined by the Vrishbhavaty river . This once clean river carries most of the sewage out of Bangalore now. Finally at the Sangama the Arkavathy meets the might Cauvery and proceeds on its journey to the sea.
Of interest to Bangaloreans would be the fact that apart from the Chikkarayapanahlli tank which holds some water none of the other tanks further down have any. The 7thth tank in the chain , the Nagarkere at Dodballapur itself is more or less empty. The once mighty Hessarghatta is a brown field with a puddle in it. The Thippagondanahally rarely fills up even half and is more or less on the way to being abandoned as a reliable source of water to the city.
This death of a river system is largely due to a complete absence of a catchment management plan . Granite quarrying continues in the Arkavathy basin. Encroachment of forest ecosystems happen. The very act of agriculture and its expansion is one of levelling land and ploughing it preventing run-off of rainwater. Rivers die when agriculture expands in its catchment.
Tanks have been encroached and the gullies linking the overflow of one tank to another silted up. Groundwater exploitation is to depths of 600 and even a 1000 feet. When the earth itself is dry is there a chance for the rivers?
A crying need is for the city to come up with a plan for the river to run always and implement it. Even a rupee a month from every citizen of Bangalore will generate more than 100 crores a year to help revive the river. Are we up-to it institutionally and otherwise? Or shall we cry in our ignorance about water shortages all the while?
While we do not care about the Arkavathy drying up are we bothered that it is the rains in the Kabini catchment that keeps the water in our taps? If so what are we doing to protect the forests of the Wynad? Will we wait for the mighty Cauvery to meet the fate
A water literate urban citizenry must engage with its river sources, its catchment and the forests. If we do not understand the problem we will never attempt the right solution. For a start take a walk to Channakesava hills.