New sewage treatment technologies to be adopted
They will be cost effective and require less land.TWAD Board to implement schemes in 18 district headquarters.Local bodies to execute schemes in six areas.Sewer network in Chennai almost complete.Conscious of the growing demand for land, authorities have decided that new technologies, requiring less land, will be adopted for execution of underground sewerage schemes (UGSS).In the past, the waste stabilisation pond technology was used for establishing sewage treatment plants in some areas. For treating one million litres of sewage a day, 2.5-3 acres was required.Now new technologies requiring less land such as fluid aerobic bioreactor, sequencing batch reactor and modified activated sludge process have emerged.
They are cost effective, according to a member of the experts' committee, which has been entrusted by the State Government with the task of identifying and recommending technology options for urban local bodies.The expert says the panel gives its advice to each local body, depending upon the requirements and suitability. A mix of technologies has been recommended in some local bodies. At present, plans for 21 district headquarters have been finalised. Perambalur and Tiruvallur received Government approval last week.
While local bodies will execute underground sewerage schemes in six district headquarters, the Tamil Nadu Water Supply and Drainage (TWAD) Board will take care of the remaining 15 district headquarters.Three more — Nagapattinam, Nagercoil and Theni — will be the Board's responsibility and Government approval is awaited. Sources say the orders will be issued next month.(Five district headquarters — Tiruchi, Madurai, Tirunelveli, Thanjavur and Karur — were covered under the National River Conservation Project seven years ago. Trial run of the network is under progress in Tiruneveli and Karur while the schemes will be completed in the remaining areas by September).
In addition to the district headquarters, the Government has sanctioned implementation of the UGSS in 10 municipalities — Komarapalayam, Rasipuram, Chinnamanur, Paramakudi, Sankarankoil, Tenkasi, Mettur, Sathyamangalam Gobichettipalayam and Maraimalai Nagar.Except Coimbatore and extended areas of Madurai, all others will receive assistance from the Tamil Nadu Urban Development Fund. The Jawaharlal Nehru National Urban Renewal Mission will cover the textile city and part of Madurai.
