"These deaths are an affront to our common humanity and undermine the efforts of many countries to achieve their development potential," he said yesterday.
In a message to mark the 2010 World Water Day event celebrated on March 22, Moon said clean water had become scarce and would become even scarcer with the onset of climate change.
He said with the scarcity of water, the poor continued to suffer first and foremost from pollution, water shortages and the lack of adequate sanitation.
"Our indispensable water resources have proved themselves to be greatly resilient, but they are increasingly vulnerable and threatened."
"Our population's need water for food, raw materials and energy is increasingly competing with nature's own demands for water to sustain already imperiled ecosystems and the services on which we depend," the UN head said.
The day, being celebrated on the theme "Clean Water for a Healthy World" emphasises that both the quality and the quantity of water resources are at risk.