The quality of freshwater worldwide is deteriorating, raising serious concerns about the health of rivers, lakes and groundwater. Despite the severity of the issue, a significant lack of data from many countries is complicating efforts to fully understand and address the problem.
Around 3.7 billion people live in areas that contribute less than 3 percent of global water quality data. This data gap is particularly concerning, as it hampers the ability to manage critical issues such as droughts, floods and pollution, a recent UN Environment report found.
Fewer than 4,500 lake quality measurements are available out of nearly 250,000 needed, highlighting the extent of the data shortage.
Recent years have seen widespread degradation of freshwater ecosystems.
Between 2015 and 2019, 61 percent of countries reported that at least one type of freshwater ecosystem was in a degraded state.
Although this figure decreased to 31 percent between 2017 and 2021, newly available data suggests that the proportion of countries with degraded ecosystems may still be around 50 percent, the UN said.
Monitoring programmes
This environmental damage is affecting 90 countries, particularly in Africa, Central Asia and Southeast Asia.
Key contributors to the decline include pollution, dam construction, land conversion, over-extraction of water and the impacts of climate change.
Addressing the decline in freshwater quality requires improved data collection and monitoring.
To help fill the data gap, UN experts recommend the expansion of government-funded monitoring programmes and suggests leveraging satellite-based Earth observation technologies and projection models to enhance data accuracy.
In France, recent issues highlight the urgency of addressing water quality.
Traces of banned pesticides have been detected in drinking water, and a quarter of French towns and cities are reported to have undrinkable tap water.
