Water Power (Hydroelectric Dams)

A short list of the detrimental effects of dams:

  • Blocks the travel of wildlife.
  • Destroys forests, agricultural land, recreation areas.
  • Alters stream flow causing disruptions in plant and animal ecology.
  • Sediment is retained behind the dam, so water scours the stream bed below the dam.

Dam Diversity

What difference does a dam make? By measuring the bug populations in the water before and after the removal of a dam on the Conestoga River in Lancaster County, Heather Calaman found that the dam was suppressing diversity. Before the dam was removed, she found 554 critters from 16 families. Afterward she found 3,783 from 30 families. Calaman believes the increase was due to the high amount of oxygen available in the faster flowing water.

-Elizabeth Monk (Research/Penn State September 2002, p 20)

Large Hydro Dams

(A good general website on dams is International Rivers Network, and you should start with their page on the problems with big dams.)

Are dams environmentally sound?

Dams Emit Greenhouse Gases

Dams, forests and people

International Rivers Network (Dams and Human Rights)

Kyoto accord signals death knell for dinosaur era fish in Canada

Canada's effort to meet the Kyoto Treaty obligation is sparking an effort to build more than 100 new hydro-electric dams in central and western parts of the country.

What organizations are helping to get rid of dams?

Northeast Megadam Resistance

Save Our Wild Salmon Coalition (Pacific Northwest US)

Glen Canyon Dam (Utah)