Environmental Impacts of Hydroelectric Power Contents Land Use Wildlife Impacts Life-cycle Global Warming Emissions Contents Land Use Wildlife Impacts Life-cycle Global Warming Emissions Hydroelectric power includes both massive hydroelectric dams and small run-of-the-river plants. Large-scale hydroelectric dams continue to be built in many parts of the world (including China and Brazil), but it is unlikely that new facilities will be added to the existing U.S. fleet in the future. Instead, the future of hydroelectric power in the United States will likely involve increased capacity at current dams and new run-of-the-river projects. There are environmental impacts at both types of plants. Learn more: How Hydroelectric Energy Works For more on the benefits of hydroelectric power and other renewable energy technologies, see Benefits of Renewable Energy Use. Land Use The size of the reservoir created by a hydroelectric project can vary widely, depending largely on the size of the hydroelectric generators and the topography of the land. Hydroelectric plants in flat areas tend to require much more land than those in hilly areas or canyons where deeper reservoirs can hold more volume of water in a smaller space. At one extreme, the large Balbina hydroelectric plant, which was built in a flat area of Brazil, flooded 2,360 square kilometers—an area the size of Delaware—and it http://www.ucsusa.org/clean_energy/our-energy-choices/renewable-energy/environmental-impacts-hydroelectric-power.html#bf-toc-0 http://www.ucsusa.org/clean_energy/our-energy-choices/renewable-energy/environmental-impacts-hydroelectric-power.html#bf-toc-1 http://www.ucsusa.org/clean_energy/our-energy-choices/renewable-energy/environmental-impacts-hydroelectric-power.html#bf-toc-2 http://www.ucsusa.org/clean_energy/our-energy-choices/renewable-energy/environmental-impacts-hydroelectric-power.html#bf-toc-0 http://www.ucsusa.org/clean_energy/our-energy-choices/renewable-energy/environmental-impacts-hydroelectric-power.html#bf-toc-1 http://www.ucsusa.org/clean_energy/our-energy-choices/renewable-energy/environmental-impacts-hydroelectric-power.html#bf-toc-2 http://www.ucsusa.org/clean_energy/our-energy-choices/renewable-energy/how-hydroelectric-energy.html http://www.ucsusa.org/clean_energy/our-energy-choices/renewable-energy/public-benefits-of-renewable.html only provides 250 MW of power generating capacity (equal to more than 2,000 acres per MW) [1]. In contrast, a small 10 MW run-of-the-rive plant in a hilly location can use as little 2.5 acres (equal to a quarter of an acre per MW) [2]. Flooding land for a hydroelectric reservoir has an extreme environmental impact: it destroys forest, wildlife habitat, agricultural land, and scenic lands. In many instances, such as the Three Gorges Dam in China, entire communities have also had to be relocated to make way for reservoirs [3]. Wildlife Impacts Dammed reservoirs are used for multiple purposes, such as agricultural ...

1. Environmental Impacts of Hydroelectric Power
Contents
Land Use
Wildlife Impacts
Life-cycle Global Warming Emissions
Contents
Land Use
Wildlife Impacts
Life-cycle Global Warming Emissions
Hydroelectric power includes both massive hydroelectric dams
and small run-of-the-river plants.
Large-scale hydroelectric dams continue to be built in many
parts of the world (including China and
Brazil), but it is unlikely that new facilities will be added to the
existing U.S. fleet in the future.
Instead, the future of hydroelectric power in the United States
will likely involve increased capacity at
current dams and new run-of-the-river projects. There are
environmental impacts at both types of
plants.
Learn more: How Hydroelectric Energy Works
For more on the benefits of hydroelectric power and other
renewable energy technologies, see
Benefits of Renewable Energy Use.
Land Use

2. The size of the reservoir created by a hydroelectric
project can vary widely, depending largely on the size of
the hydroelectric generators and the topography of the
land. Hydroelectric plants in flat areas tend to require
much more land than those in hilly areas or canyons
where deeper reservoirs can hold more volume of water
in a smaller space.
At one extreme, the large Balbina hydroelectric plant,
which was built in a flat area of Brazil, flooded 2,360
square kilometers—an area the size of Delaware—and it
http://www.ucsusa.org/clean_energy/our-energy-
choices/renewable-energy/environmental-impacts-hydroelectric-
power.html#bf-toc-0
http://www.ucsusa.org/clean_energy/our-energy-
choices/renewable-energy/environmental-impacts-hydroelectric-
power.html#bf-toc-1
http://www.ucsusa.org/clean_energy/our-energy-
choices/renewable-energy/environmental-impacts-hydroelectric-
power.html#bf-toc-2
http://www.ucsusa.org/clean_energy/our-energy-
choices/renewable-energy/environmental-impacts-hydroelectric-
power.html#bf-toc-0
http://www.ucsusa.org/clean_energy/our-energy-
choices/renewable-energy/environmental-impacts-hydroelectric-
power.html#bf-toc-1
http://www.ucsusa.org/clean_energy/our-energy-
choices/renewable-energy/environmental-impacts-hydroelectric-
power.html#bf-toc-2
http://www.ucsusa.org/clean_energy/our-energy-
choices/renewable-energy/how-hydroelectric-energy.html
http://www.ucsusa.org/clean_energy/our-energy-
choices/renewable-energy/public-benefits-of-renewable.html

3. only provides 250 MW of power generating capacity (equal to
more than 2,000 acres per MW) [1].
In contrast, a small 10 MW run-of-the-rive plant in a hilly
location can use as little 2.5 acres (equal to
a quarter of an acre per MW) [2].
Flooding land for a hydroelectric reservoir has an extreme
environmental impact: it destroys forest,
wildlife habitat, agricultural land, and scenic lands. In many
instances, such as the Three Gorges
Dam in China, entire communities have also had to be relocated
to make way for reservoirs [3].
Wildlife Impacts
Dammed reservoirs are used for multiple purposes, such as
agricultural irrigation, flood control, and
recreation, so not all wildlife impacts associated with dams can
be directly attributed to hydroelectric
power. However, hydroelectric facilities can still have a major
impact on aquatic ecosystems. For
example, though there are a variety of methods to minimize the
impact (including fish ladders and in-
take screens), fish and other organisms can be injured and killed
by turbine blades.
Apart from direct contact, there can also be wildlife impacts
both within the dammed reservoirs and
downstream from the facility. Reservoir water is usually more
stagnant than normal river water. As a
result, the reservoir will have higher than normal amounts of
sediments and nutrients, which can
cultivate an excess of algae and other aquatic weeds. These
weeds can crowd out other river animal
and plant-life, and they must be controlled through manual

4. harvesting or by introducing fish that eat
these plants [4]. In addition, water is lost through evaporation
in dammed reservoirs at a much
higher rate than in flowing rivers.
In addition, if too much water is stored behind the reservoir,
segments of the river downstream from
the reservoir can dry out. Thus, most hydroelectric operators are
required to release a minimum
amount of water at certain times of year. If not released
appropriately, water levels downstream will
drop and animal and plant life can be harmed. In addition,
reservoir water is typically low in
dissolved oxygen and colder than normal river water. When this
water is released, it could have
negative impacts on downstream plants and animals. To
mitigate these impacts, aerating turbines can
be installed to increase dissolved oxygen and multi-level water
intakes can help ensure that water
released from the reservoir comes from all levels of the
reservoir, rather than just the bottom (which
is the coldest and has the lowest dissolved oxygen).
Life-cycle Global Warming Emissions
Global warming emissions are produced during the installation
and dismantling of hydroelectric
power plants, but recent research suggests that emissions during
a facility’s operation can also be
significant. Such emissions vary greatly depending on the size
of the reservoir and the nature of the
land that was flooded by the reservoir.
http://www.ucsusa.org/clean_energy/our-energy-
choices/renewable-energy/environmental-impacts-hydroelectric-
power.html#references

5. http://www.ucsusa.org/clean_energy/our-energy-
choices/renewable-energy/environmental-impacts-hydroelectric-
power.html#references
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choices/renewable-energy/environmental-impacts-hydroelectric-
power.html#references
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choices/renewable-energy/environmental-impacts-hydroelectric-
power.html#references
Small run-of-the-river plants emit between 0.01 and 0.03
pounds of carbon dioxide equivalent per kilowatt-hour.
Life-cycle emissions from large-scale hydroelectric plants
built in semi-arid regions are also modest: approximately
0.06 pounds of carbon dioxide equivalent per kilowatt-
hour. However, estimates for life-cycle global warming
emissions from hydroelectric plants built in tropical areas
or temperate peatlands are much higher. After the area is
flooded, the vegetation and soil in these areas
decomposes and releases both carbon dioxide and
methane. The exact amount of emissions depends greatly on
site-specific characteristics. However,
current estimates suggest that life-cycle emissions can be over
0.5 pounds of carbon dioxide
equivalent per kilowatt-hour [5,6].
To put this into context, estimates of life-cycle global warming
emissions for natural gas generated
electricity are between 0.6 and 2 pounds of carbon dioxide
equivalent per kilowatt-hour and
estimates for coal-generated electricity are 1.4 and 3.6 pounds
of carbon dioxide equivalent per
kilowatt-hour [7].
References:

6. [1] Fearnside, Phillip M. 1989. Brazil's Balbina Dam:
Environment versus the legacy of the Pharaohs
in Amazonia. Environmental Management, July/Aug 1989,
Volume 13, Issue 4, pp 401-423.
[2] National Renewable Energy Laboratory (NREL). 2012.
Renewable Electricity Futures Study. Hand,
M.M.; Baldwin, S.; DeMeo, E.; Reilly, J.M.; Mai, T.; Arent, D.;
Porro, G.; Meshek, M.; Sandor, D. eds.
4 vols. NREL/TP-6A20-52409. Golden, CO: National
Renewable Energy Laboratory.
[3] Yardley, Jim. November 19, 2007. Chinese Dam Projects
Criticized for Their Human Costs. New
York Times.
[4] National Renewable Energy Laboratory (NREL). 2012.
Renewable Electricity Futures Study.
[5] IPCC, 2011: IPCC Special Report on Renewable Energy
Sources and Climate Change Mitigation.
Prepared by Working Group III of the Intergovernmental Panel
on Climate Change [O. Edenhofer, R.
Pichs-Madruga, Y. Sokona, K. Seyboth, P. Matschoss, S.
Kadner, T. Zwickel, P. Eickemeier, G.
Hansen, S. Schlömer, C. von Stechow (eds)]. Cambridge
University Press, Cambridge, United
Kingdom and New York, NY, USA, 1075 pp. (Chapter 5 & 9).
[6] National Academy of Sciences. 2010. Electricity from
Renewable Resources: Status, Prospects,
and Impediments. Washington, DC: The National Academies
Press. Online at
http://www.nap.edu/openbook.php?record_id=12619

7. [7] IPCC, 2011: IPCC Special Report on Renewable Energy
Sources and Climate Change Mitigation.
http://www.ucsusa.org/clean_energy/our-energy-
choices/renewable-energy/environmental-impacts-hydroelectric-
power.html#references
http://www.ucsusa.org/clean_energy/our-energy-
choices/renewable-energy/environmental-impacts-hydroelectric-
power.html#references
http://www.ucsusa.org/clean_energy/our-energy-
choices/renewable-energy/environmental-impacts-hydroelectric-
power.html#references
http://www.springerlink.com/content/l0504508pv1632u2/fulltex
t.pdf
http://www.nrel.gov/analysis/re_futures/
http://www.nytimes.com/2007/11/19/world/asia/19dam.html?pa
gewanted=all
http://www.nrel.gov/analysis/re_futures/
http://srren.ipcc-wg3.de/report/
http://srren.ipcc-wg3.de/report/
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Week 6 Due Aug 11
Select one of the schizophrenic or dissociative identity
disorders from the Film List.
Choose one and watch youtube on films on demand
· Schizophrenia
· Dissociative identity disorder
Use the Research Analysis Job Aid to complete this assignment.
Prepare a 1,050- to 1,500-word paper that discusses research-
based interventions to treat psychopathology.
Review and differentiate the characteristics of the selected
disorder and discuss the research about intervention strategies
for the disorder by completing the following:
· Evaluate three peer reviewed research studies using the
Research Analysis.
· Conceptualize the disorder using the biopsychosocial or
diathesis-stress models.
· Discuss the treatments or interventions that have been shown
to be the most effective for your selected disorder. Why?
Cite at least five peer-reviewed sources.
Format your paper consistent with APA guidelines.