A United Nations report to be released this week will reveal that half of the world’s 500 biggest rivers are seriously depleted.

The Nile and Indus are greatly reduced by the time they reach the sea; the Colorado and Yellow River rarely reach the ocean at all; the Jordan and Rio-Grade are dry for much of their length.

This week’s UN report will officially warn the world’s governments of an “alarming deterioration” in the planet’s rivers,lakes and other freshwater systems, a “disaster in the making” according to the report.