A repercussion of COVID-19 lockdown on water quality along the east coast of India.

The COVID-19 pandemic and subsequent lockdown measures significantly impacted various sectors, including coastal environments. While restrictions led to temporary improvements in air quality, their effects on coastal waters remained understudy. This research conducted four cruises along the east coast of India during pre- and post-COVID-19 lockdown to assess the water quality changes. Results show a significant increase in Chl-a (31.8%), DO (28.1%), and SDD (7.7%), while reductions in NO3 (34.7%), PO4 (51.7%), SiO4 (16.2%), TSM (25.4%), TC (72.3%), and FC (83.3%) were observed. Multivariate analysis identified land-based pollution as the primary source of pollution in coastal waters. Overall, the findings suggest improved coastal water quality during the lockdown. However, for the sustainability of coastal waters, it is proposed that raw sewage, wastewater, and atmospheric fluxes affecting coastal water quality must be regulated.