Positive and Negative Repercussions on Global Water Systems
When the World Health Organization declared COVID-19 a global pandemic in March 2020, governments worldwide implemented unprecedented lockdown measures that dramatically altered patterns of daily life. As industries ground to a halt, streets emptied of traffic, and tourism ceased almost entirely, an unexpected environmental story began to unfold beneath the surface of our waterways. From the suddenly-clear canals of Venice to the improving water quality of India's Ganges River, the natural world responded rapidly to this sudden reduction in human activity 6 .
The dramatic reduction in industrial activity, transportation, and tourism during lockdown periods created an unexpected environmental benefit—significantly improved water quality in many regions around the world.
The water in the canals turned remarkably clear due to the absence of boat traffic that would normally stir up sediments from the bottom 6 .
Improved Clarity40-50% substantial upgrade of water quality based on measurements of dissolved oxygen, biochemical oxygen demand, and total coliforms 6 .
40-50% ImprovementSuspended particulate matter decreased by 15.9% on average during lockdown, with some areas showing reductions up to 36.4% 3 .
15.9% ReductionSurge in medical and plastic waste, including masks and gloves that frequently found their way into water bodies in Hong Kong, Canada, and other regions 6 .
Plastic PollutionHeightened focus on hygiene led to elevated levels of surfactants in wastewater, affecting organic matter structure and bacterial communities in treatment systems 9 .
Chemical ImpactDomestic water use increased by 20-30% in India and up to 40% in Jordan, placing additional stress on water resources and treatment infrastructure 2 .
Resource StrainMedications used to treat COVID-19 consist of "persistent, bioaccumulative and dangerous substances to aquatic organisms," and they are considered emerging pollutants that conventional wastewater treatment cannot completely eliminate 6 . The increased use of disinfectants—both institutional and household—introduced new chemicals into wastewater systems, presenting new challenges for wastewater management 9 .
A landmark study focused on Vembanad Lake in India demonstrated the power of remote sensing technology 3 . Researchers utilized Landsat-8 Operational Land Imager (OLI) imagery from April 2013 to April 2020 to track changes in suspended particulate matter (SPM), a key indicator of water pollution.
The dramatic improvements demonstrated the remarkable resilience of aquatic ecosystems when given respite from constant human pressure, offering hope that effective intervention can yield relatively quick benefits.
The expansion of wastewater-based epidemiology and successful use of remote sensing technologies demonstrated powerful new applications for water monitoring that will benefit public health beyond the pandemic 1 .
As we move forward, the lessons from this period should inform more resilient and sustainable approaches to water management. By recognizing both the positive and negative impacts revealed during this extraordinary time, we can work toward water protection strategies that preserve both human and environmental health in the face of future challenges.