Model STP all set to stop pollution of Kollidam

TRICHY: Trichy corporation has successfully completed a test run on the city’s first decentralised sewage treatment plant (STP) on Kollidam flood bank road near Yatri Nivas in Srirangam. The model plant with a capacity to treat 2MLD (million litres per day) of wastewater excluding sewage, will remove pollutants and contaminants from the water discharged by houses and commercial properties to prevent pollution in the Kollidam river passing through Srirangam.

Though the core areas of Srirangam falling under wards 1 to 4 were covered by underground drainage (UGD) network in 2002-03, grey water (wastewater from kitchens and bathrooms) was not connected to the network. Only sewage outlets from toilets were linked to the UGD network in Srirangam. Around 6,000 properties in Chithirai, Uthirai and Adayavalanjan streets near Srirangam temple were discharging their grey water into stormwater drains. Eventually, the drains let the wastewater into the flood carrier Kollidam river where Trichy city’s six major drinking water sources are located. The massive borewells in the riverbed address about 60% of the city’s drinking water needs.

Dozens of washerman families in the city rely on the Kollidam for their livelihood too. Realising the need to safeguard the river, Trichy corporation had proposed the decentralised STP for Srirangam last year and sanctioned Rs 1.3 crore for it in two instalments. The construction work of the STP was completed and a successful trial run held recently. The plant which works on advanced oxidation process technology will use chemical coagulants such as aluminium sulphate to treat the wastewater.

Sprawling over 11,000 square feet between STEM park and Yatri Nivas, the STP has three massive tanks for collection and flocculation to remove suspended waste, pollutants and sludge as well as to perform oxidation in the water treatment process. “The treated water is odourless and colourless, fit to be used for cleaning and gardening. Washerman families relying on Kollidam river will benefit the most as the poor water quality of the river was affecting their livelihood,” a corporation official told TOI.

The local body added that the pH (acidity-basicity levels) of the treated water was around 7, which was neutral on pH scale. Trichy corporation plans to install new pipelines to discharge the retreated water, which conforms to Tamil Nadu Pollution Control Board (TNPCB) standards, into Kollidam riverbank abutting Srirangam helipad complex. The facility will be commissioned after the Lok Sabha election model code of conduct is withdrawn.