Lake Information

Varthur Lake is an artificial lake, or tank, located in the Bangalore South taluk of the Bangalore District in Karnataka. This lake has played an important role in maintaining water resources for irrigation since its construction during the Ganga Empire over 1,000 years ago (Karnataka State Gazetteer, 1990). Over the centuries, it has developed into a complex ecosystem that provides habitat for a variety of plant and animal species, including resident and migratory waterfowl. The lake also endows the local community with a pleasant microclimate and considerable aesthetic appeal.

However, over the past two decades the land use around the lake has transformed. From being primarily agricultural land, the area is rapidly getting urbanised, which can be seen in the maps below. The consequence of this development being the lack of dependence on the lake as a source of water and hence, the reduced supervision & sense of responsibility towards the lake. The capacity of water in the lake also has fallen from 6.10 Mm3 (in 1800) to 1.61Mm3  (current)2. The effect of urbanisation has taken some heavy toll on the lake and is evident in the current state of the lake.

Varthur Lake is today a highly polluted lake contaminated with domestic sewage, waste water and industrial effluents though decades of misuse. Experts suggest Varthur lake is in stasis for 2.5 years till interventions are finished, in an upstream lake - Bellandur, (a major source of water for Varthur). Investigation of current government plans, however suggest it is likely to remain polluted for many more years still.

What is the Problem?

The problem we face today is uncertainty with regard to how do we act at Varthur when its future is so tightly linked to the future of lakes upstream that remain polluted. How do we act in the face of absolute financial, regulatory and infrastructural inaction by the state? How do we act in the lake measuring 180 acres to have a positive, visible impact in the quality of water, the ecology of the lake, safeguarding the interest of people that still depend on it.

Website: A canvas for dialogue

What's
The
Problem?

Varthur Lake is today a highly polluted lake contaminated with domestic sewage, waste water and industrial effluents though decades of misuse. Experts suggest Varthur lake is in stasis for 2.5 years till interventions are finished, in an upstream lake - Bellandur, (a major source of water for Varthur). Investigation of current government plans, however suggest it is likely to remain polluted for many more years still.

The problem we face today is uncertainty with regard to how do we act at Varthur when its future is so tightly linked to the future of lakes upstream that remain polluted. How do we act in the face of absolute financial, regulatory and infrastructural inaction by the state? How do we act in the lake measuring 180 acres to have a positive, visible impact in the quality of water, the ecology of the lake, safeguarding the interest of people that still depend on it.

What are the key issues?

  • Poor water quality

  • Foaming and fire at  the lake 

  • Extensive weed growth

         A threat to aquatic life, public health

  • Lake encroachment & illegal waste dumping

  • Strong, foul smell in the lake surroundings

Why is Varthur Lake polluted?

Incoming water is mainly black & waste

Composed of sewage, solid waste, soap, detergents, industrial effluents etc 

Secondary source of water, 30 MLD:

28 Inlets around Varthur

Primary source of water 560MLD: Bellandur outlet

LAKE AREA:

180.40 ha / 445.8 ac

What is the future?

Sewage generation in the catchment is only going to grow

Decadal population growth in the Varthur catchment 2001-11 has been an astounding 45% 

As per KSPCB regulations, apartments of > 50 units are supposed to manage their own STPs but rest of the houses are still supposed to be served by BWSSB. At Varthur such apartments make up just 21.5%

SOURCES

21% HHs are apartments, mandated to have in-site STPs

79% HHs release their sewage into the storm water, which flows into the lake

78.5%

21.5%