Tapi river turns bright green to the horror of residents in Surat

Surat (Gujarat): Tapi river, which is a lifeline for the residents, industries and farmers in Surat, has changed from appearing blue to appearing bright green, indicating the serious presence of sediments and algae, likely caused by anthropogenic activities, according to the study.

Tapi river has changed its colour to ‘Green’ in the upstream at the weir-cum-causeway—a lone source for the Surat Municipal Corporation (SMC) to draw river water through its huge intake wells and quench the thirst of the 55 lakh population.

MHS Shaikh, president of the Brackish Water Research Centre (BWRC) visited the spot to find the waters of the Tapi river changed colour from blue to green. Shaikh collected the water samples and after testing found that the water was highly polluted due to anthropogenic activities.

Shaikh was surprised when he came across the wastewater flowing directly into the weir-cum-causeway from the SMC’s Sewage Treatment Plant (STP) at Kosad, instead of its original disposal point in the Tena creek connected to the Arabian sea.

“The combination of sewage degraded water, industrial wastewater, fertilizer waste from the agricultural fields in the upstream etc. contribute heavily to the water pollution and ultimately on the health of the residents in Surat,” said Shaikh. “It is shocking as to how the Kosad STP is releasing wastewater upstream of Tapi river when the water is supposed to be disposed of in the Tena creek?”

According to Shaikh, phosphate, sulphur, and nitrate are the nutrients that help the algae grow. The nutrients can also come from agricultural land and sewage. Such highly polluted water is life-threatening for lakhs of people getting tapped water supplied by the SMC. . The green colour appears when there are large amounts of algae due to fertiliser runoff from farms, sewage and industrial waste.

The residents, meanwhile, claim that this is the first time that the Tapi has turned ‘so green’.

Shailesh Manek, a resident of Singanpore, which is located close to the weir-cum-causeway said, “I was surprised to find the waters in Tapi river have turned bright green. A couple of days back the watercolour was blue. I have been living in this area for the last two decades and this is the first time that the river has changed its colour”