‘Car service effluents pollute surface water bodies’

A study has found that waste water from automobile service stations pollute the water bodies as much as industrial effluent.

Two students pursuing Bachelors in Science held the study under the supervision of Vivekananda degree college chemistry department HOD Prof Sripathi L.

They visited over 30 service stations in Basaveshwarnagar, Mahalakshmi Layout, Vijayanagar, Malleshwaram, and Rajajinagar Industrial suburb.

The study is titled, “Survey of surface water bodies’ pollution due to waste water discharge from unorganised automobile service stations location in residential sector of Rajajinagar”. One of the students who did the study, Gowtham Raghavendra CK, said Rajajinagar has the highest number of service stations due to its vehicle density. “Each of these stations service not less than 30 vehicles a day. The waste water is either allowed on to the streets or released into the storm water drains,” he added.

Nithin C V, another student who took part in the studies, said the effluent water pollutes fruit-bearing trees
in the area, besides the water bodies. Depending on their sizes, the vehicles washed in the service stations take 161.4 to 227.4 liters of water.

This means the waste water released by the stations is far larger.

Analysis done on the effluent water revealed that it has five times more Biochemical Oxygen Demand (BOD) than the Bureau of Indian Standards (BIS) values for tolerance limits. Similarly the waste water has seven times more chemical oxygen demand (COD), 107 times more oil and grease, twice more than the limits set for iron and settable solids.

Mixing with fresh water, the oil and grease depletes dissolved oxygen and impairs photosynthesis fatal for aquatic life, besides which it also dangerously contaminates the water source.