The Maharashtra Pollution Control Board (MPCB) has released a report stating that seawater as well as quality of water in Mumbai and Thane districts is deteriorating. The report also shows that samples of seawater collected from the two cities have consistently recorded a drop in the Water Quality Index (WQI) from bad to very bad.
The report, 'Water Quality Status of Maharashtra' for 2018-19, also shows that the seawater at Mumbai beaches falls in the range of medium to bad.
Human settlements and industrial establishments around the creeks and places near Mumbai seashore are mainly held responsible for the deplorable condition of water.
The report reveals how untreated and semi-treated sewage water generated from industrial areas of the two cities and human waste get mixed with water, thereby, causing quality of water to drop drastically.
WQI is calculated using 43 parameters. Out of this, pH level, dissolved oxygen, biochemical oxygen demand (BOD) and faecal coliform are core parameters.
A WQI of above 63 indicates "good to excellent" surface water quality, while WQI of 38 and less indicates "bad to very bad" water quality or heavily polluted. This is non-drinkable.
Ten saline water stations monitoring Mumbai sea water showed levels of faecal coliform content and biochemical oxygen demand has shot up 9 times than the safety levels, says the report which was prepared with the help of The Energy and Resource Institute (TERI).
Saline water quality monitoring takes place at 36 locations. It represented four districts along the Maharashtra coastline whereas 10 saline water quality management are installed in Mumbai district while Thane, Raigad and Ratnagiri districts have 19, three and four saline WQMS installed respectively.
Mithi River near Mumbai's Mahim bridge has the worst WQI, an average of 30, which is not suitable for drinking while seawater near Gateway of India averages 49, which means it is very bad quality. And overall Mumbai water samples, is at an average of 50.