Taste for waste
Chennai Metro Water claims that no less than 98.6 per cent of the city is connected to the sewerage. If the rainfall (and consequently the water supply) is normal in Chennai, it generates 300 million litres per day (MLD) of sewage. It has a treatment capacity of 262 MLD, but the treatment is only up to the secondary level. Of this 27 MLD is sold to industrial units in Manali, where it is further treated and processed for use. 262 MLD of sewage is treated in four major and one small treatment plant. The major plants are: Koyembedu (treats 34 MLD, Nesapakkam (23 MLD), Perungudi (45 MLD) and Kodungaiyur (160 MLD). Four waterways traverse the city. They are: Buckingham canal, Otteri Nallah, and Adayar and Cooum rivers. These are all eyesores at present. They have been reduced to conduits of sewage and industrial effluents.
The flat rate of Rs 50 that Metro Water charges domestic consumers includes water supply and sewage disposal charges. "In addition, a water supply and sewerage tax is collected once in two years. It comes to about 7 per cent of the rental value of the property,' says Madhavan Murthy, the utility's chief engineer.
Metro Water claims only 17 per cent of the city's sewage is untreated. One visit to the waterways nails their lie. Even the Central Pollution Control Board points out the level of biological oxygen demand (and indicator of pollution) in the Cooum river is 480 milligramme per litre (mg/l) as against the maximum permissible limit of 3 mg/l. Why does Metro Water lie? Well, it doesn't know for sure the amount of water Chennai uses. How will it calculate the amount of sewage?
Chennai has 4.46 million people. If it is assumed that the water consumption is 200 litres per capita daily, the amount of sewage can be estimated at 700 MLD. The amount of untreated sewage, hence, is 448 MLD, which is 63 per cent of the total sewage