Ibalur Lake Case Study

Lakes are relatively small to large water bodies surrounded by land on all sides sustaining an ecosystem in and around them. Lakes have been an integral part of the ecological system by providing natural abode for plants, animals and microorganisms. Increase in urbanization and industrialization has led to the destruction and in the reduction of lakes in the city of Bangalore, Surviving lakes in Bangalore are reduced to cesspools due to direct discharge of industrial effluents and unregulated dumping of solid wastes (Ramchandra 2007). Water bodies like lakes readily acquire pollutants because they are complex and a fragile ecosystem and do not possess self-cleaning ability (Abida et al., 2008). Industrial activities, urban and agricultural
The lake is situated off the Sarjapura outer ring road nearing to the Sun City apartments.
The lake is enclosed by a small park for the purpose of walking and recreation, the existence of the lake is unnoticed due to developments, fast moving traffic and the fully fledged growth of exotic weeds mainly the water hyacinth and other higher plant weeds. The approximate area of the lake is about 1000 meters from the road side and the water in the lake is confined to a centralized basin of around 600 meters.

1. Sampling method
a. Physico-chemical and microbiological
The parameters like pH, calcium, hardness and total alkalinity exceeded the permissible limits of WHO; whereas parameters like magnesium, sodium, nitrates, chlorine and sulphates were found to be within the permissible value. The content of Dissolved oxygen found to be present in the lake water was found to be nil, hence the values of biological oxygen demand and the chemical oxygen demand were also found to be zero. This proves that water quality of Ibalur Lake does not sustain aquatic life. Bacteriological examination of water performed through most probable number analysis showed that MPN index per 100ml of the water sample were found to be maximum, presence of coliform bacteria was confirmed using EMB and nutrient agar medium which clearly indicates that the water could not be used for domestic and agricultural purposes. Eco toxicological studies done on the invertebrate system zebra fish showed deleterious effects which is depicted in table-2. The zebra fish embryos could not survive in the undiluted water sample but when diluted to 10-6 times drastic changes were observed with respect to heart beats which decreased tremendously, complete change in the morphology of the embryo. A severe change was noticed in the spinal cord region of the fish. The changes could be the same or even with a large magnitude in higher animals if the lake water is used. This is