America deserves a clean energy future and with the continued growth of renewable energy, we are on the right track. But not all renewable energy technologies are created equal. Some, like hydropower, come with significant downsides. Though hydropower can be a low-carbon technology, it can produce outsized harm to water quality, fish, wildlife, and communities that depend on healthy rivers.
Think Hydropower is “clean and green” energy? Think again.
Hydropower plants often divert water around entire sections of river, leaving them dry, which destroys habitat as well as fishing and boating opportunities.
Hydropower dams are a significant source of water pollution. Scientists and legal scholars have long acknowledged that hydropower dams cause pollution by altering the temperature and chemical makeup of water that is impounded behind and released through dams, harming the biological integrity of river ecosystems.
Hydropower reservoirs are a significant (and largely unaccounted) source of methane, a potent greenhouse gas. Best estimates put the contribution of hydropower to climate change at roughly equivalent to that of Canada.
Rivers are public resources – they belong to all of us. It simply isn’t fair to allow hydropower companies to prioritize private profits at the expense of communities and river health.
If hydropower is going to be the clean energy resource we need for the 21st century, its impacts must be taken seriously and addressed. We’ve seen improvements in siting, operation, and mitigation over the last 30 years thanks to safeguards like the Clean Water Act and the Endangered Species Act. These laws, applied through the FERC licensing process, have made hydropower cleaner and our rivers healthier.
But we still have a long way to go and, unfortunately, some members of Congress and the hydropower industry are trying to stop this progress. We must not go back to the days when energy companies destroyed rivers with impunity. We must insist on hydropower operations that put the health of our rivers and communities first.
 Pringle, Catherine M. Mary C. Freeman, and Byron J. Freeman (2000). Regional effects of hydrologic alterations on riverine macrobiota in the new world: Tropical-temperate Comparison, BioScience, Vol. 50 No. 9, pp. 807-823.
 National Marine Fisheries Service (yr) Status of Sacramento River Winterrun Chinook Salmon, 59.
 Richter, Brian D., Ruth Mathews, David L. Harrison, and Robert Wigington (2003) Ecologically Sustainable Water Management: Managing River Flows for Ecological Integrity, Ecological Applications, Vol. 13, No. 1, pp. 206-207.
 Abell R. (1994) San Juan River Basin Water Quality and Contaminants Review, 78- 79.
 EPA (1989) Dam Water Quality Study: Report To Congress.
 Deemer, 2016