Rivers in trouble around the world

Rivers in trouble

The world’s rivers are in trouble. That’s according to a new study published in September 2010 in the journal Nature that analyzed human impacts on rivers worldwide. The study looked at how things like chemical and agricultural pollution, and water overuse threaten rivers’ water supply. Peter McIntyre of the University of Wisconsin co-authored the study.

Peter McIntyre: What we’ve found is that 80% of the world’s population lives in areas where the threats to river systems are high.

In the U.S. and elsewhere, we rely on technological fixes – our water systems – for water that is pure enough to drink. McIntyre said these systems are giving us a false sense of security.

Peter McIntyre: You and I, we go home, we turn on our tap, we have relatively pure, healthy fresh water, all that we could want to use, so we feel we have high water security. The issue is, in the background, things on the whole are getting worse with more people and more resource use.

Meanwhile, in the developing world, nations can’t afford expensive technological fixes for their river systems. The threat there is more immediate.

Peter McIntyre: If you’re one of the folks in the world that has to draw your water directly from a river, you’re drawing from a river that’s likely to be contaminated. That’s the plight that over a billion people worldwide are in. Overall, we find that there are many areas in North America and Western Europe, and South and East Asia where threat levels are high relative to the rest of the world.

Rivers, said McIntyre, are our most important renewable source of fresh water.

Peter McIntyre: All of life depends upon water and at the same time water becomes the ultimate ground where all of the problems, all of the shifts, the changes we cause to the environment comes to roost. So if you put chemicals onto the land, they aren’t just staying on the land, they’re going into the water.

McIntyre said that in his study, the level of threats to rivers correlated with how many people live nearby – the more people, the higher the threat level. And the U.S. and Western Europe are among the most densely populated and developed places on the planet, he said.

Peter McIntyre: The U.S. and Western Europe have dramatically altered the structure and functioning of our rivers. There’s no two ways about it. We have very high density of dams, we’ve lost wetlands and flood plains on almost every river basin in those regions. We high levels of agricultural and industrial chemicals that get into our water, you need only to go to your local fishing hole and the odds are there will be a sign that says, “Don’t eat the fish.”