Effects of Covid–19 Pandemic on Surface Water Quality: A Case Study in Hong–Thai Binh River, Vietnam

The Covid-19 epidemic that appeared and broke out from the end of 2019 until now has contributed to limiting human production and emissions. As a result, the quality of the global environment tends to be good, including the water environment. The impact of the Covid-19 epidemic on the water environment has been studied by us in the Hong-Thai Binh river of Vietnam. Data at 30 water monitoring points on the Hong-Thai Binh in the period of 2018 - 2021 were used to calculate water pollution indexes including: Comprehensive Polluted Index (CPI), Organic Pollution Index (OPI) and Trace Metal Pollution Index (TPI). The results show that the average values of all three indicators CPI, OPI, TPI on the Hong-Thai Binh river in the period of during the Covid-19 (from 2020 to 2021) were higher than their values before (from 2018 to 2019). This implies that the blockade and social distancing activities implemented during Vietnam's Covid-19 epidemic have disrupted production activities and reduced the amount of waste discharged into the Hong-Thai Binh river. As a result the river water quality has been improved. To protect the water quality of the Hong-Thai Binh river in particular and the quality of the water environment in general, measures to strictly control waste sources and transform the economy from linear to circular are recommended solutions for Vietnamese government in the post-Covid-19.