Why I Give a Dam a Thought

July 30, 2015

I’m fairly new to the party of people who are concerned about dams and rivers. When I explain to friends and family that I’m focusing on an effort to increase the awareness of the ‘dam’age from dams, I get some strange looks. However, I reason that if I didn’t get some strange looks, I wouldn’t need to focus on this issue.There are many reasons why I’ve come to feel passionate about the need for free-flowing rivers. At the core of my concern is protecting and restoring our earth’s natural systems for creating a habitat where wildlife and humans can prosper. What greater sustenance is there on earth than fish and fresh, clean water? Fish have been an important source of protein and other nutrients for humans throughout recorded history. According to the Food and Agriculture Organization of the United Nations, “Many of the world’s poorest people depend on fish.…Just over 100 million tons of fish are eaten world-wide each year, providing 2.5 billion people with at least 20% of their average per capita animal protein intake.”What I’ve learned is that dams have wiped out some fish species and have imperiled others by hindering their inability to spawn and causing changes in water quality. The next Let Rivers Flow newsletter will focus on this topic. Fish hatcheries which have been built, at least in part to help replenish the dwindling wild fish supply, have problems with in-breeding and disease. According to Science Daily, “Steelhead trout that are originally bred in hatcheries are so genetically impaired that, even if they survive and reproduce in the wild, their offspring will be significantly less successful at reproducing.” More on this here.

On the Coosa River, AL

And what about water quality? We can’t survive without clean, fresh water. Dams hinder the natural cleansing process of free-flowing rivers which carry sediment all the way to the ocean building beaches and delta habitats. Instead, silt backs up, many times collecting chemicals and pollutants, and can require expensive dredging to allow vessel passage. Check out this story on an Ohio dam removal where the cost of removing polluted sediment ($3.5M) is the bulk of the entire dam removal expense.

Fresh water mussels are natural cleaning machines for rivers. Mussels need flowing water to reproduce and dams can hurt the reproduction of mussels by taking away the host fish that are needed to carry the mussels’ embryos. According to the Virginia Department of Game and Inland Fisheries, over 70% of the U.S. mussel species are endangered due to pollution, dams and invasive species. Read more here. Because of the long lifespan of many mussels (upwards of 40 years), it is believed that we haven’t seen the true impact of mussel species destruction yet.

Hydropower dams do provide our world with significant amounts of electricity, (20% globally and 9% in the U.S., according to Statistic Brain) which many argue is cleaner than fossil fuel. However, the expense of maintaining dams is increasing as many dams are aging and require continual maintenance. In addition, the expense of silt management and fish hatcheries add heft to the cost of dams. More importantly, the great majority of dams have long since outlived their purpose, and are sitting idle, holding back wild, flowing rivers.

The number of free-flowing rivers is small. According to the World Wildlife Federation, ‘out of 177 rivers longer than 600 miles, there are only 64 free-flowing rivers left in the world.’ There are only 6 in the U.S.

I don’t expect to see fast changes made with dams. But, I do hope to see increased awareness of the impact dams have on us, our rivers and wildlife.

“Wild rivers are earth’s renegades, defying gravity, dancing to their own tunes, resisting the authority of humans, always chipping away, and eventually always winning.”
Richard Bangs, River Gods

Photo courtesy of Beth Young