Goa’s Mandovi river was cleaner during lockdown months, study confirms
The water quality of Goa’s Mandovi river showed significant improvement during the Covid-19 lockdown in 2020 thanks to a steep reduction in human activity, a National Institute of Oceanography study has found. The midstream sections of the river that usually show a high proportion of coloured dissolved organic matter (CDOM) were found to be clearer by almost two folds, it added.
“The concentration of dissolved nutrients in 2020 was also low compared to the previous reports. There was a complete standstill of anthropogenic activities such as operating pleasure cruises, water transport systems like barges, shipbuilding activities, and commercial establishments following the government-imposed lockdown, which might have reduced the CDOM and nutrients in the estuary,” the research said.
The lockdown provided the first-ever opportunity to study the water column characteristics of Mandovi Estuary when most of the anthropogenic activities were either stopped or reduced drastically. The water quality of the Mandovi is known to be poor because of bacterial presence and dissolved oxygen.
The presence of CDMO is one of the parameters to examine water quality.
The researchers carried out sampling in the Mandovi Estuary in early May 2020 during the phased lockdown opening to compare the CDOM absorption during the spring inter-monsoon (March–May) of 2014–2018 with that of 2020 when the anthropogenic activities were minimal.
The 81-kilometre long Mandovi river originates in Karnataka and along with its tributaries irrigates over half of Goa’s cultivable area.