The Nature Conservancy does not advocate the building of dams or other large water-related infrastructure projects. However, we recognize that despite the threats they pose to natural systems, more dams and diversions will be built to meet humanity’s needs. 
 
Because this development poses significant risks to the world’s freshwater ecosystems, the Conservancy believes that it is important to engage with those responsible for this growth in an effort to minimize the environmental and social threats posed by these projects. 
 
Read the Frequently Asked Questions below to see how we help ensure that new dams and large diversions and water withdrawals are located, built and operated in ways that promote a more sustainable future for freshwater ecosystems and the people who depend on them.

Why doesn't the Conservancy oppose all new dam building?

Conservation organizations have historically fought against the construction of dams that can be harmful to the plants, animals, and natural systems we seek to protect. However, today governments and industry are racing to provide power to the more than two billion people who lack electricity for heating, lighting their homes and refrigerating their food and serve the needs of over one billion people that lack access to clean drinking water. 

Increasingly, new hydropower and water supply projects are considered as potential sources for meeting current and projected future needs. The Nature Conservancy seeks to give nature a seat at the table so that the ecological implications of developing a river’s hydropower and water supply potential are fully understood. Where projects are already moving forward, we seek to integrate ecological health into decisions affecting the placement, design and operation of future dams.   

Will the Conservancy ever directly oppose a project?

Yes. There are cases where a proposed water development project is so poorly conceived and would cause such significant environmental and social harm that the Conservancy would oppose the project. Generally speaking, however, the Conservancy invests its time, energy and resources in trying to influence the location, design and operation of projects. 

We strongly encourage governments and development agencies to:

• Conduct comprehensive water and energy development plans to realistically evaluate water and energy needs;
• Consider a full range of options for meeting those needs; and
• Select projects that are as environmentally benign as possible within both the local and regional context.  

I’ve heard hydropower described as a clean energy source that doesn’t exacerbate climate change.  If so, isn’t this the kind of energy source that a conservation organization should be promoting over other more polluting options?

As our energy demands increase, we will need more energy from the rivers of the world as well as from other sources. However, we should carefully evaluate the costs of each choice and each project. Although hydropower produces much less pollution than coal, fuel, or oil, and does not emit greenhouse gases directly, it is not environmentally benign. 

The Nature Conservancy believes that most hydropower projects can be designed and operated in a more ecologically sustainable manner, thereby reducing the harm they cause to the environment. Our work toward this goal is guided by science and in partnership with industry, governmental agencies, scientists, local communities, non-governmental organizations, and others. Technological innovations, efficiency gains, and the expansion of other, more environmentally benign, energy sources must also be part of a more ecologically sustainable energy future.     

Haven’t dam managers always considered ecological health in their operations?

No. Until now, dams have been designed to supply water (primarily for irrigation and municipal uses), control floods, generate electricity, and create reservoirs for recreation. The goal of “minimizing ecological impacts” has seldom been taken seriously. The Nature Conservancy has developed a scientific approach to quantifying the water flows and other habitat conditions needed to support ecological health and can help dam builders and managers integrate this information into dam design and operations.  

Doesn't your work to improve the ecological sustainability of dams allow dam builders to deflect criticism about the environmental harms caused by their projects? 

No.  We are not a regulatory agency and we have no financial stake in these projects.  Because we have no means to enforce our viewpoint, responsible parties may choose to incorporate or ignore the guidance we provide.  Our involvement does not make approval of a dam project or its operational guidelines by relevant government agencies or international lending institutions more likely. 

When appropriate, to ensure that our involvement with a dam builder or responsible party is not misconstrued, we develop specific agreements that clearly state that our involvement does not signify our support for the dam or approval of its environmental performance.  

Do you have experience working with dam builders or water management agencies?

Yes. We are reinvigorating many degraded rivers by improving dam operations through partnerships with water agencies — such as our work with the U.S. Army Corps of Engineers in nine river basins in the United States. 

In China and Honduras we are working with energy agencies that are planning new dams to help them avoid or minimize ecological damage. In other cases, such as the Penobscot River in Maine, or the Neversink River in New York, we are working with dam owners and regulators to remove dams to restore natural flows and historic fish migration patterns to rivers.

What are the social impacts of dams?

New dams are often proposed in areas where people live and use rivers to meet their subsistence or other livelihood needs. Hydropower projects generally result in the flooding of large areas by creating a reservoir behind the dam, potentially displacing farms and villages. A dam also substantially changes the character of water flow, temperature, and chemical quality below the dam, potentially affecting a community’s ability to farm or fish, travel and trade between settlements, or conduct other necessary activities. 

History is full of examples of dams built without adequate analysis of environmental and social impacts and where the local communities and inhabitants were not adequately consulted, engaged, or fairly compensated for their losses. As stated previously, the Conservancy believes the parties responsible for building new dams must be engaged and encouraged to minimize the environmental and social threats posed by these projects. The Conservancy strives to provide not only a seat for nature at the table but also an opportunity for local communities and inhabitants to influence a project. Through this engagement, we can help ensure that new dams are located, built and operated in ways that will promote a more sustainable future for freshwater ecosystems and the people who depend on those systems.

Nature picture credits (top to bottom, left to right): Photo © George Schuler (Neversink River Dam, New York); Photo © Mark Godfrey (The Stevens Creek dam and rocky shoals on the Savannah River northeast of Augusta, Georgia).