Surface Water Quality Variation Under the Influence of COVID-19 Quarantine on the Example of the Yamuna River (Delhi)

During the current COVID-19 pandemic, various forms of lockdown have been adopted, globally. This study evaluated the contamination changes (pre, post and during the lockdown) in the Yamuna River following the nationwide COVID-19 lockdown from 25 March–30 May (India). Samples of the surface water were taken from 9 sampling points to determine the physico-chemical, and biological concentration changes in surface water. The investigation showed the fluctuating results of the parameters. The peak saturation of physico-chemical parameters were observed prior to lockdown, followed by the post and during lockdown phases. The BOD and COD concentrations declined by 66% and 39.25%, respectively, compared to the pre-lockdown phase, while Faecal Coliform declined by over 40%. The improvement shown in this period indicates that it is possible for the Yamuna River to be cleaned up easily if people and the government come together.

Assessment of Surface Water Quality using Indices and Geographic Information System in the Sebou River Basin, Morocco

The aim of this study is to access the quality of monitored rivers and to map the polluted river sections in the Sebou basin using Geographic Information System (GIS). The potential causes of water quality variation will also be added for suitable measures to be taken. A Water Quality Index (WQI) which developed in Morocco was applied to 17 river water quality monitoring stations with data on 6 parameters (Dissolved oxygen (DO), ammonium ion (NH4 + ), 5-day biochemical oxygen demand (BOD5), chemical oxygen demand (COD), fecal coliforms (FC) and total phosphorus (TP)) collected twice during the wet and dry season over 1990-2017 period. The result shows that river water quality is classified as bad, very bad and medium at 59% of the monitoring stations, while 41% are considered as good to excellent. Interpolation of mean values of overall WQI of the 17 river water quality monitoring stations, revealed evidence of quality degradation along several kilometers of most river sections in the Sebou basin. The correlation matrix between the sub-indices of water quality parameters and the overall WQI showed high positive correlation coefficients and highlights the contribution to water quality degradation as follows: TP (𝑟 = +0.96 ) ≥ NH4 + (𝑟 = +0.96 ) > BOD5 (𝑟 = +0.94) > COD (𝑟 = +0.86) > FC (𝑟 = +0.83) > DO (𝑟 = +0.79). The sections of Fès, Innaounene Rivers, and an extended stretch of Tizguit River must no longer be used for irrigation. River water quality is overall of better quality in the wet season compared to the dry season. Simple linear regressions between the seasonal water quality variation and the overall WQI showed higher coefficients of determination R 2 (0.67 and 0.60) between dry season WQI and the overall WQI and between wet season WQI and the overall WQI respectively. It is clear that discharges of industrial and domestic wastewater during the dry season and agricultural activities are most likely to be the causes of the degradation of river water quality.

Assessment of Water Quality of Odor River, Anambra State

Aim: This study examined the physicochemical and bacteriological parameters of Odor River in Orumba North, Anambra State. The parameters considered were pH, turbidity, temperature, Dissolved Oxygen (DO), Alkalinity, total hardness, Sulphate ( ), Chloride, Calcium ( ) hardness, Magnesium ( ) hardness, Iron (Fe), Nitrate (NO3-), Conductivity, Total Dissolved Solids (TDS), Total coliform and Escherichia coli (E. coli). The objectives of the study were to assess the similarities that exist amongst the physicochemical and bacteriological parameters of Odor River in Orumba North, Anambra State. Also, to test whether water from Odor river is safe for drinking by the people of Orumba North and its environs. Methodology: The Cluster analysis and the one-sample T-test method were used to analyze the data obtained for this study. Results: The findings of the study revealed that the parameters can be grouped in two groups as follows: group A consists of pH, turbidity, temperature, Dissolved Oxygen (DO), Alkalinity, total hardness, Sulphate ( ), Chloride, Calcium ( ) hardness, Magnesium ( ) hardness, Iron (Fe), Nitrate (NO3-), and Conductivity while group B consists of Total Dissolved Solids (TDS), Total coliform and E.coli. The physicochemical parameters were found to impact significantly on the variation of the water quality at 5% significant level and their measures did not exceed the World Health Organization (WHO) standard. Further findings revealed that the bacteriological parameters such as the Escherichia Coli and Total Coliform do not significantly impact on the water quality variation of the river and their measures do not exceed the WHO standard. Conclusion: The physicochemical and bacteriological parameters of Odor River were found to be within the WHO Standard. However, the physicochemical parameters were found to impact on the water quality variation of the river while the bacteriological parameters do not impact on the variation of the water quality of the river. The implication of the physicochemical and bacteriological parameters not exceeding the WHO standard indicates no risk for the users of the river. Hence, water from Odor River is safe for human consumption and agricultural purposes.