For instance, the total coliform level in Kammasandra Lake is 240 million MPN/100ml; in Seegehalli Lake, it is 2.4 million MPN/100ml; in Varthur Lake, it is found to be 17 million MPN/100ml; and in Kammagondanahalli Lake it is 2.2 million MPN/100ml. Groundwater experts say while the lake water is not directly being used for drinking purposes, it can contaminate shallow water aquifers in the area, rendering them unfit for drinking too.
From Electronic City, the lake stream starts from the Shikaripalya Lake to Maragondanahalli Lake and connects to Tirupalya Lake, Hebbagodi, Kammasandra Lake, Bommasandra Lake, Heelalige Lake, Chandapura, Muthanallur, Bidaraguppe from where it then goes to Dakshina Pinakini or Penne river.