1 Introduction
Varthur Lake, which has an area of 180.40 hectares (445.8 acres) is the second largest lake in Bangalore city and also one of the most polluted lakes in Bangalore. Its ecosystem is under continuous degradation because of sewage water from Bangalore, entering the lake from Bellandur Lake further upstream.
This is a man made lake, built by Ganga kings over thousands of years ago for agriculture and domestic uses but now the lake is receiving 40% of the sewage water from Bangalore for over 50 years resulting in eutrophication.
The article is expected to become the definitive guide for the Varthur lake: issues, plans, actions, and current status.
2 Issues
Varthur Lake is dead and we want to bring it back to life. Here are the stats:
- Encroachments everyday despite alerting authorities
- Ground Water depth decreasing at an alarming pace
- Heavy metals in Lake water affecting ground water as well
- Toxic Foam severely affecting passersby
- BOD: 250 vs ideal of 30! Study shows effect on those using the water from nearby bore-wells.
- Depth 5 feet vs earlier 35 ft.
- Even the hardiest of fish ie Catfish – dying
- Massive breeding ground for mosquito larvae. 2 km radiums affected
- Hyacinth covers over 50% of the lake
- Steady , speedy encroachments observed
- Increasing volume of sewage and garbage observed headed to Varthur Lake.
- As per NGT, apartments that are supposed to treat their sewage and reuse, should not let out the excess sewage into UGDs.
- BDA has invited brickmakers to take the silt.
- We request corporates, Real Estate Developers, Road contractors, residential communities etc. to reuse the silt by leveraging the technology developed by CMRIT professor and his students
3 Get well plan
3.1 Phase 1
Desilt
3.2 Phase II
- Rebuild Wetland
- Address the massive 400 MLD influx of untreated sewage + water coming in from Bellandur.
- Address Sewage coming in from 21 Inlets
4 Critical Dependencies
- The Lake is owned by BDA but many agencies need to co-ordinate for success. This is a very critical dependency
- Large volume of untreated Sewage gushing down from Bellandur
5 Open issues
- Upstream sewage issues continue. This article is depressing as it suggests that the action that the govt is taking is in the wrong place.
- How to dispose what we remove from the dredging – Ownership BDA
6 Risks
- Unless the Bellandur Sewage onslaught is addressed, Varthur cannot get well.
- Unless the STP downstream for Varthur is built, the UGD being laid across Whitefield now will terminate into the lake!
7 Key Stakeholders
- BDA Commissioner, TV Ramachandra, NGT, KSPCB, Lake Expert Committee Rep
- Varthur Corporator : Pushpa Manjunath, Hagadur Coporator: Uday Kumar, Doddanekundi Corporator: Shweta , MLA: Arvind Limbavali
- Citizens: Whitefield Rising, KK English School
8 Actions underway
- DPR for Dredging and Desilting underway
- Dewatering and Diverting sewage to get the lake ready for desalting
- BDA has started Dewatering the lake
- BDA is building A temporary diversion drain is divert the sewage that is coming in, to make sure the lake bed dries up so that desilting can start.
- BDA has called for expressions of Interest to rejuvenate the lake.
- 7. Timelines:
- As per the recent NGT order, BWSSB Needs to ensure no sewage enters the lake, else a 5 lakh penalty shall be levied per inlet per month. NGT has indicated this penalty will be recovered from the officers responsible currently , as well as in the past.
- The Bangalore Water Supply and Sewage Board (BWSSB) Sewage Treatment Plants (STPs) are to be ready by September 2020
9 Action History
| S.No | Action | Owner | Date | Date/Status |
|---|---|---|---|---|
| 1 | Rectify lake bed and buffer encroachmentsat Thubarhalli and Bellandur Amani Kere villages. Install fencing. | BDA | 01-May-2017 | May-12-2017:Survey markings completed.Concrete fence poles are being installed |
10 References
10.1 Disappearing Varthur Wet Lands
10.2 Varthur Lake is a source of breeding ground of mosquitoes
10.3 Media Coverage
Minor Irrigation Dept to take over city’s lakes-Bangalore Mirror(July 29th 2017)
10.4 Links
1. Rising Citizen Facebook page: https://www.facebook.com/risingcitizen
2. Soil dumping near Thubarhalli a video: https://www.facebook.com/risingcitizen/videos/vb.623094701223985/665916366941818/?type=2&theater