Ganga being cleared of algal bloom near famous Varanasi ghats
River Ganga’s stretch between famous Dashashwamedh and Assi ghats in Varanasi was sprayed with chemicals on Sunday to clear it of algal bloom, which was discharged from a sewage treatment plant in Mirzapur and spread rapidly due to presence of nitrogen and phosphorus in river waters, traced to untapped drains in the Varanasi district, officials said.
The algal bloom was removed using 3000 liters of bioremediation solution made with 7.5 kg chemical powder. Another 3000 liters will be sprayed in the affected stretches on Monday and the efficacy of the exercise will be assessed on Tuesday by carrying out spot inspection, the team involved in the cleaning exercise said.
The team was headed by Neeraj Gahlawat, project officer-technical, National Mission for Clean Ganga (NMCG), NMCG Varanasi convener Rajesh Shukla and city health officer Dr NP Singh.
Shukla said the spray solution helped clear algal deposits from the stretch within hours by Sunday afternoon.
Varanasi district magistrate Kaushal Raj Sharma said the algal bloom was first detected in Ganga over 20 days ago but it disappeared briefly around a week ago. A team of experts, constituted on June 7 after its reappearance, collected water samples, which were tested by UP pollution control board’s laboratory. It was found that the algae strains came from a STP in Mirzapur.
“The algae strains drained into the river Ganga from Mirzapur district’s Chunar oxidation pond and STP. This algae flourished in Varanasi stretch of River Ganga due to presence of nitrogen and phosphorous (though mild) which mainly come in the river water from untapped drains,” UPPCB scientific officer Dr TN Singh said, referring to two untapped drains supplying nitrogen and phosphorous for the algae to bloom. One of these drains with 50 MLD capacity discharges into the river in Asi area, while the second one with 10 MLD capacity drains into the river in Ramnagar area of the district, he said.