Farming in Arkavathi catchment area drying up TG Halli

A study has revealed that an increased irrigation and commercial crop cultivation along the catchment of River Arkavathi is the primary cause of low water levels in the Thippagondanahalli (TG Halli) reservoir. 

Ashoka Trust for Research in Ecology and the Environment (ATREE), which did a study on “Why is the Arkavathi River Drying? A multiple- hypothesis approach in a data- scarce region” shows that it is not only low rainfall which has led to declining water level in the reservoir but also because of over exploitation of the catchment area of Arkavathi basin for Nandi Hills to TG Halli in Bengaluru west. 

The total catchment area of the reservoir is 532 square miles and the water spread area is 2.64 square miles. 

Sharatchandra Lele, author of the paper and Senior Fellow and Convenor, Centre for Environment and Development, ATREE said in the last 25 years of irrigation around the catchment area has more than doubled. Satellite imageries also show that for two seasons during 2013-14, most areas in the north and north east of the catchment areas on Bengaluru-Tumakuru highway and west of Doddaballapur towns are under eucalyptus plantations. Agriculture is around 20%  of the catchment area and its distributed all along. Ground water yields are better in downstream areas and can be seen around the 300 villages like Hesaraghatta and Madhukere. Farmers are cultivating commercial crops for Bengaluru market like coconut, vegetables, banana and grapes. Though there is no accurate record of how many borewells have been drilled in the catchment areas, but a look at the crops show that there are many, he said. 

Lele added that there is no effective implementation of the High Court ban on eucalyptus plantation. The only way to increase water levels at TG Halli reservoir is by having a combination of basin-level institutions working with gram panchayats. There is a need to create a water budget at every gram panchayat level. We have started preparing a detailed water budget report which will be released in six months. It will include details like how much water should be allocated to farming for irrigation and agriculture and how many borewells should be dug in each site.