Last updated on: 10/27/2009 | Author:

Should the US Build More Hydropower Dams?

General Reference (not clearly pro or con)

Glenn F. Cada, PhD, Researcher at the Oak Ridge National Laboratory Environmental Sciences Division, et al., stated the following in their April 2007 article “Potential Impacts of Hydrokinetic and Wave Energy Conversion Technologies on Aquatic Environments,” published in the journal Fisheries:

“Conventional hydroelectric projects, with dams and reservoirs, are used all over the world to produce renewable energy. In the United States, conventional hydropower supplies 7% of the nation’s electricity. The value of hydropower and other renewable energy sources is seen in renewed appreciation in light of increasing concerns about the effects of fossil fuel and biomass combustion on carbon dioxide levels in the atmosphere and global climate change. However, the ability of conventional hydropower to meet our increasing energy demands is limited, owing to a variety of environmental concerns, including degradation of fish passage, water quality, and aquatic and terrestrial habitats.”

Apr. 2007

The US Environmental Protection Agency (EPA) stated the following on its webpage “Hydroelectricity,” available at (accessed Oct. 14, 2009):

“The movement of water as it flows downstream creates kinetic energy that can be converted into electricity. A hydroelectric power plant converts this energy into electricity by forcing water, often held at a dam, through a hydraulic turbine that is connected to a generator. The water exits the turbine and is returned to a stream or riverbed below the dam…

Currently, facilities in the U.S. can generate enough hydropower to supply electricity to 28 million households, which is equivalent to about 500 million barrels of oil. In 2003, total hydropower capacity in the United States was 96,000 MW. The undeveloped capacity for the United States is approximately 30,000 MW.”

Oct. 14, 2009

PRO (yes)


Lew Tagliaferre, retired Executive Director of the Electrical Contracting Foundation, stated the following in his July 2008 article “Renewing Interest in Hydropower,” available at the Buildings website:

“In addition to its extremely high efficiency (up to 93 percent), hydropower also provides many other social and environmental benefits. Too often, hydropower is overlooked by policymakers and the public in debates on energy and environmental policy…

One myth that continues about hydropower is that it’s a tapped-out resource…

To demonstrate this, currently pending before the Federal Energy Regulatory Commission (FERC) are license applications for 430 megawatts of conventional hydropower capacity and 900 megawatts of new pumped-storage capacity. Another 448 megawatts of conventional hydropower and 2,783 megawatts of pumped storage are before the commission in the pre-filing stage, before a license application is submitted…

Electricity generated by conventional hydropower and new ocean, tidal, and in-stream hydrokinetic resources reduces the need for additional generation from fossil fuels and avoids the emissions associated with those resources…

By expanding the support for hydropower resources, power consumers could obtain energy and environmental benefits of existing hydropower projects and infrastructure, as well as the emerging suite of new waterpower technologies.”

July 2008


The National Hydropower Association (NHA) provided the following testimony, in a June 6, 2007 statement delivered by Tim Culbertson, to the US Senate Committee on Energy and Natural Resources Subcommittee on Water and Power hearing titled “Impact of Climate Change on Water Supply and Availability in the United States,” available at the NHA website:

“Beyond the fact that it is renewable, climate friendly, and domestic, hydropower offers some advantages over other resource options. Hydropower provides significant generation, peaking capacity, and ancillary services to bolster the reliability, stability, and resilience of the nation’s transmission system…

Today, hydropower accounts for approximately 77% of the actual renewable electricity generation and 83% of the nation’s renewable energy capacity. As robust a resource as hydropower is today, there remains tremendous growth potential for the industry…

If the U.S. is serious about its response to the effects of climate change, then federal support for the development of this untapped potential is necessary.”

June 6, 2007


The National Rural Electric Cooperative Association provided the following testimony during the June 12, 2008 US House Natural Resources Committee Subcommittee on Water and Power oversight hearing “Hydropower: Providing 75 Percent of America’s Renewable Energy and Exploring Its Role as a Continued Source of Clean, Renewable Energy for the Future,” available at the House Committee on Natural Resources website:

“Some have called for the breaching of our federal dams. This would be completely counter to the long-standing federal hydropower commitment and policy. This is not the time to create additional energy challenges for this country… We must invest in our federal hydropower infrastructure and reverse the ‘break-down’ maintenance practice that has put the federal hydroelectric infrastructure in such a dire state of disrepair.

NRECA [National Rural Electric Cooperative Association] urges Congress and future Administrations – Republican or Democrat – to take all steps necessary to maximize the reliability and efficiency of the existing federal hydropower assets and to identify and pursue all opportunities to expand these facilities. These assets are an essential part of the national strategy for addressing global climate change and ensuring that consumers have enough electricity.”

June 12, 2008

CON (no)


American Rivers, a non-profit river conservation organization, stated the following in its article “Hydropower Dams in an Era of Global Warming,” available at its website (accessed Oct. 13, 2009):

“Hydropower dams will continue to play a role in our nation’s energy portfolio. But we cannot responsibly meet our nation’s 21st century energy needs by damming new rivers or by weakening environmental protections designed to protect rivers from harmful dam operations…

Low-power dams (many of which are physically quite large, despite insistence by developers that they are ‘small’) harm streams in the same ways as dams that produce more power. Multiple low-power dams scattered on multiple streams add up to major environmental impacts that can be greater than that of a single large dam…

Dams disrupt flows, degrade water quality, block the movement of a river’s vital nutrients and sediment, destroy fish and wildlife habitat, impede migration of fish and other aquatic species, and eliminate recreational opportunities. Reservoirs slow and broaden rivers, making them warmer. The environmental, economic, and societal footprint of a dam and reservoir may extend well beyond the immediate area, impacting drinking water, recreation, fisheries, wildlife, and wastewater disposal.”

Oct. 13, 2009


Cheryl Nenn, MS, Great Lakes Regional Representative of the Waterkeeper Alliance, stated the following in an Apr. 23, 2009 article titled “Why Hydropower Is Not a Feasible Option for Estabrook Dam,” available at Milwaukee Riverkeeper website:

“All dams disrupt stream flows, degrade water quality, impede migration of fish, damage fish and wildlife habitat, and diminish or eliminate recreational opportunities. Dams cause physical and chemical changes to our waterways, including altering flow regimes and sediment transport for miles beyond the actual dam site…

Most of the viable hydropower sites in the US have already been constructed; sites that are left provide marginal power while putting tremendous strain on aquatic resources.

Most hydropower dams licensed by FERC produce very little energy; 80% of dams produce less than 50 MW of power, which is enough electricity to power 50,000 homes. New hydropower facilities are functionally obsolete due to increasing strides in energy efficiency, creation of more promising renewable energy technologies including solar and wind power, and negative environmental impacts of hydropower.

Even ‘small’ hydropower units cause serious environmental damage…

The costs of building new hydropower dams far outweigh the benefits. Building new dams in the name of ‘renewable energy’ is not justifiable.”

Apr. 23, 2009


International Rivers, a non-profit river conservation organization, stated the following in its July 2008 fact sheet “Dammed Rivers, Damned Lives: The Case Against Large Dams,” availible at its website:

“Millions have lost land and homes to the canals, roads and other infrastructure associated with dams. Many more have lost access to clean water, fish, grazing land and other resources…

Sixty percent of the world’s major rivers have been fragmented by dams and diversions. Large dam and diversion schemes have stopped some of the world’s major rivers, such as the Indus, the Nile and the Colorado, from reaching the sea. In the early 1900s, the Colorado River delta supported a rich array of egrets, jaguars and other wildlife. However, the heavily plumbed river now only reaches the delta in rare flood years and wildlife populations have plummeted.The number of indigenous people who once fished and farmed the delta has also declined…

Dams and diversions are the main reason why one-third of the world’s freshwater fish species are extinct, endangered or vulnerable. Many shellfish, amphibians, plant and bird species that depend on freshwater habitats are also extinct or at risk…

Viable alternatives to dams do exist, and are frequently more sustainable and cheaper.”

July 2008