Lakes of Bengaluru: Restored in 2019 but entry of sewage still a problem in Devasandra lake

According to the KSPCB, the water quality index of Devasandra lake is Class D which means that propagation of wildlife and fisheries is possible. (Express photo by Jithendra M)

Local residents have been demanding a solution to the problem. In his study on the status of restored lakes in Bengaluru published in January 2020, Dr T V Ramachandra, wetland specialist, Centre for Ecological Sciences at the Indian Institute of Science (IISc), said, “This lake (Devasandra lake) though restored recently, still receives untreated sewage water through inlets. The lake water is highly turbid and green due to algal growth and suspended particles. High macrophyte (aquatic plant) and algal growth reduced nutrient contents in the lake water. Water has high organic contents.”

Ramachandra has studied the condition of 45 lakes which were claimed to have been restored by the BBMP. Among the restored waterbodies, only six lakes — Jakkur, Kempambudhi, Devasandra, Ullal, Handrahalli and Agrahara — were found to be in a decent condition compared to the 39 others.

Laying emphasis on the importance of the Devesandra lake, Ramachandra said, “The lake helps in groundwater recharge, supports diversity of birds and serves recreational purposes.”

Lake activist Balaji Raghotham said, “The lake is upstream of the Seegehalli lake. Devasandra lake receives good rainwater. While the lake is well maintained, the entry of sewage is a problem.”

While the BBMP had restored the lake, according to their own document on encroachment of the lakes, 0.85 acre of the total extent of Devasandra lake has been encroached. (Express photo by Jithendra M)

Environmentalist Dinesh M, who lives in K R Puram, said, “Industrial effluents in K R Puram enters into the Devasandra lake through the inlets. The untreated sewage also enters the lake. BBMP should address the issue.”

While the BBMP had restored the lake, according to their own document on encroachment of the lakes, 0.85 acre of the total extent of Devasandra lake has been encroached.

Amongst encroachment by the government bodies, 0.56 acre has been encroached by the railway department, 0.074 acre has been taken over by the BBMP for the construction of roads and 0.03 acre for a graveyard. Eight private encroachers have been accused by the BBMP of having either built houses or fenced portions of the lake.

However, the private encroachments were not cleared and the BBMP went ahead with the restoration of the lake. “We had restored the lake in association with NGO United Way and diversion lines for sewage were constructed. The entire lake was cleaned and restored. Today, the lake is in a good shape when compared with the condition in which it was six-seven years ago. We have fenced the lake and constructed toilets and a waste weir. Earlier, there used to be complaints of open defecation and garbage dumping in the lake,” a BBMP engineer said.

In 2017, a government-appointed ‘Koliwad Committee’ on lakes directed the revenue department to recover one acre of the Devasandra lakebed encroached by a shopping mall.