Opening the first major UN meeting on water resources in nearly half a century, Secretary-General, Antonio Guterres told nearly 6.500 participants, including a hundred ministers and a dozen heads of state and government, that humanity has "broken the water cycle, destroyed ecosystems and contaminated groundwater".
The world is "blindly travelling a dangerous path" as "unsustainable water use, pollution and unchecked global warming are draining humanity's lifeblood," UN Secretary General Guterres said ahead of the start of a UN water conference in New York on 22 March.
The conference is expected to address the needs of billions of people at risk from an "imminent" global water crisis, according to a report by UN-Water and Unesco published on Tuesday, the day before World Water Day.
Richard Connor, lead author of the report, explained that the impact of the "world water crisis" will be a "matter of scenarios."
"If nothing is done, it will be a business-as-usual scenario - it will keep on being between 40 and 50 percent of the population of the world that does not have access to sanitation and roughly 20-25 percent of the world will not have access to safe water supply."
With the global population increasing every day, "in absolute numbers, there'll be more and more people that don't have access to these services," he said.
Water action agenda
At the UN conference, governments and actors in the public and private sectors are invited to present proposals for a so-called water action agenda to reverse that trend and help meet the development goal, set in 2015, of ensuring "access to water and sanitation for all by 2030."
The last conference at this high level on the issue, which lacks a global treaty or a dedicated UN agency, was held in 1977 in Mar del Plata, Argentina.
Some observers have already voiced concerns about the scope of these commitments and the availability of funding to implement them.
"There is much to do and time is not on our side," said Gilbert Houngbo, chair of UN-Water, a forum for coordinating work on the topic.
'Water scarcity is becoming endemic'
The report, published by UN-Water and Unesco, warns that "scarcity is becoming endemic" due to overconsumption and pollution, while global warming will increase seasonal water shortages in areas with abundant water as well as those already strained.
"About 10 percent of the world's population lives in a country where water stress has reached a high or critical level," the report says.
According to the most recent UN climate report, published Monday by the IPCC expert panel, "roughly half of the world's population currently experience severe water scarcity for at least part of the year."
Those shortages have the most significant impact on the poor, Connor said.
"No matter where you are, if you are rich enough, you will manage to get water," he added.
The report notes the particular impact of existing water supplies becoming contaminated due to underperforming or nonexistent sanitation systems.
No safe drinking water for billions
"At least 2 billion people use a drinking water source contaminated with feces, putting them at risk of contracting cholera, dysentery, typhoid and polio," the report notes.
That estimation does not take into account pollution from pharmaceuticals, chemicals, pesticides, microplastics and nanomaterials.
To ensure access to safe drinking water for all by 2030, current levels of investment would have to be tripled, the report says.
Freshwater ecosystems - which in addition to drinking water, provide life-sustaining economic resources and help combat global warming - "are among the most threatened in the world," the report warns.
"We have to act now because water insecurity is undermining food security, health security, energy security or urban development and societal issues," said Henk Ovink, the Dutch special envoy for water.
"It's now or never as we say - a once in a generation opportunity."