Buoyed by the success of a ‘natural sewage treatment plant (STP)’, the state government is planning at least 16 more such units to treat sewage flowing into the Yamuna.
The natural STP in the heart of Bawana industrial area was installed in July last year. It uses natural material such as pebbles and aquatic plants to clean sewage flowing through the Ghoga drain that starts from the Ghoga village and joins the Bawana escape drain.
At least 10 lakh litres of sewage is treated every day this way.
“The results have been very encouraging. The Biological Oxygen Demand (BOD), which is a measure of organic pollution, has come down from more than 300 to around 30 – 35. Other pollutants such as Total Suspended Solids (TSS) and Ammonical Nitrogen have also dropped drastically,” said a senior official in-charge of three districts.
The STP, which is around 300m long and around 5m wide with concrete walls, comprises of a sedimentation tank where the sewage is allowed to stand for the total suspended solids to settle down. Water is then passed through four chambers and multiple compartments, which have beds of pebbles of various sizes. This stage filters the sewage.
Read more of this in a report by Joydeep Thakur published in Hindustan Times...
