Countries around the world have implemented lockdowns to contain the spread of COVID-19 infection. The impact of lockdown on actual people’s mobility and the physical, chemical, biological quality of water have never been analyzed simultaneously. This study aimed to address this gap by monitoring water quality on the Siak River, one of the deepest rivers in Indonesia, characterized by the highest dissolved organic carbon recorded globally due to the contributing peat soils. Human mobility before and after the implementation of nationwide lockdown was quantified using social media data. Sampling was carried out on the Siak River in 2018, 2019, and 2020 at sixteen monitoring locations. The samples were analyzed for physical, chemical, heavy metals, biological quality. Nutrients and heavy metals concentrations indicated that Siak River was medium to heavily contaminated. Lockdown presents an immediate reduction in movement, people’s mobility on average was reduced by 33%, to improvements in water quality in terms of NH₄⁺, NO₃⁻ concentrations with a 14% reduction compared to the pre COVID-19 values, and a 30% reduction in heavy metals contamination. The reduction was attributed to decrease farming activities and farm supplies. This was because the Siak River was heavily influenced by dissolved organic carbon from peatland.

This paper presents an assessment of groundwater quality and quantum in the command areas of two secondary canals in lower Sindh, the southern province of Pakistan. These canals off-take from Rohri main canal of Sukkur barrage in the Indus basin system. The scarcity of canal water is due to climate change, population growth and increased water demands. The farming community uses groundwater to meet the needs and improve their livelihood. The fresh groundwater in Sindh is only 22 percent, which is available in shallow aquifers underlain by salty groundwater of marine nature. The groundwater quality was assessed using electrical resistivity survey (ERS), which portrayed groundwater zones through 1D inversion software (IX1D) and geospatial tool inverse distance weighted (IDW). Four classes (fresh, marginal fresh, marginal saline, and highly saline) have been delineated at different depths from 25 to 150 m below ground surface. The groundwater aquifers are identified, and their quantum is estimated. The ERS results were also compared with the quality of collected water samples at various depths. The ERS results have identified fresh groundwater up to 40 m depth. The marginal quality groundwater could be utilized to increase crop productivity through conjunctive use with the canal water.