An Indian boy drinks water from a tap on the roadside in Amritsar on March 22, 2013, World Water Day. Eighty percent of sewage in India is untreated and flows directly into the nation's rivers, polluting the main sources of drinking water.

"Water holds the key to sustainable development," said UN Secretary General Ban Ki Moon in a video address today for World Water Day. "We must work together to protect and carefully manage this fragile finite resource."

It's the 20th anniversary of the United Nations holiday, but even after years of attempting to call attention to the severe lack of clean water in areas all over the world, millions still don't have access to clean drinking water or functional sanitation systems.

The UN estimates over 783 million people (one in ten of the world's population) do not have access to clean water, while 2.5 billion do not have access to adequate sanitation or a toilet. Meanwhile, thousands of children die daily from waterborne illnesses like cholera and dysentery.

That said, the numbers have improved over the years, according to WaterAid chief Barbara Frost, who wrote an editorial today for CNN.

Frost says that 2 billion people have gained access to clean water in the past two decades of work, and that if all goes according to plan, the problem could be alleviated by 2030.

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"The difficulty will be that those who currently don't have access to this essential resource are the most difficult to reach, the most marginalized, the poorest, and the most politically disenfranchised," writes Frost. "But that is also why getting water to those without is so important. Access to clean water has always been the foundation of human development, and it continues to this day, but thankfully, most of us can now take this for granted."

But as optimistic as this sounds, ending the world's water problems can't just be up to the NGOs and international agencies partnering with the United Nations to achieve the Millennium Development Goals, one of which is cutting in half those who don't have access to clean water.

At the rate it's going, the water target may be reached by 2075, according to an Al Jazeera report.

Countries, too, must step up to the plate and do the right thing to ensure access to safe water, part of the initiative by the UN this year, under the theme "cooperation."

Israel, for example, withholds access to an aquifer from Palestinians in the West Bank. Although Ramallah gets more annual rainfall than London, there is a devastating shortage of clean water for residents of the Occupied Territories.

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"Since 1967, Israel has not allowed Palestinians to dig wells in the Western Aquifer, the largest and most productive source of water in the West Bank," says Thirsting for Justice, a water-advocacy group in Occupied Palestine. "In Gaza, 90 to 95 percent of the Coastal Aquifer, on which Gaza inhabitants are dependent for water, is contaminated due to over extraction and sewage contamination, making it unfit for human consumption."

In Haiti, a lack of clean water and adequate sewage has made it impossible to quell a cholera epidemic that has been raging for over a year, but political instability and uneasy resources only exacerbate the issue in a country known for squandering international aid money.

Improving access to clean water and sanitation, however, is a lynchpin issue that will get the ball rolling on reaching the other MDGs, such as maternal health, child development, and overall poverty, says UN Deputy Secretary General Jan Eliasson.

This year's World Water Day is devoted to promoting the idea of "cooperation" between governments and their people, between neighboring countries, and between humans themselves, to begin focusing with renewed energy on fighting for water rights.

"If we do water and sanitation right, we can have a great improvement on other goals," Eliasson said to the Associated Press.

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