River Periyar in Kerala is again witnessing decolourisation.
Details:
- The decolourisation of River Periyar which provides drinking water to Kochi city and adjoining areas has become the cause of worry for the people and government of Kerala.
- The water turned pitch black in one stream, it was milky near the Pathalam regulator-cum-bridge.
Cause of the change in colour- Eutrophication
- The pollution control Board (PCB) has attributed the change in colour to the poor quality of water as a result of eutrophication.
- PCB has stated that huge quantities of organic load in the form of sewage from nearby townships are regularly reaching the river system.
- This is contributing to the eutrophication, resulting in the change of colour.
About River Periyar:
- River Periyar flows in the state of Kerala.
- It originates in the Western Ghats and flows north for a short distance to Periyar Lake.
- Periyar Lake is an artificial reservoir created by Mullaperiyar Dam across the river.
- From the Periyar Lake, a tunnel carries water through mountains to the Vaigai River in Tamil Nadu, where it is used for irrigation.
- Further downstream Idukki dam is constructed across the river.
- The river descending out of the mountains into the coastal plain, empties into the Arabian Sea.