There are tens of thousands of dams around the country that no longer serve the purpose they were built to provide and whose removal could eliminate the cost and liability associated with owning a dam. Unless they are well maintained, their condition only gets worse every year. The most cost-effective and permanent way to deal with obsolete, unsafe dams is to remove them

1. Hydroelectric dams: the
good, the bad and the ugly
Kella Randolph
Copyright 2019

2. Water for Electricity
• This form of electricity uses the flow of water to turn a
turbine and generate electricity. As the human population
continues to grow, the need for electricity is going to grow as
well. Building a hydroelectric dam can be a great way to
provide this electricity for an area.
http://3.bp.blogspot.com/-kf6j2UJP8wI/T_cZEbKkfCI/AAAAAAAAD1w/4wWgOv_dLDc/s1600/hydro.jpeg https://upload.wikimedia.org/wikipedia/commons/a/a9/Hydroelectric_power_plant_Glendo_Sp.JPG

3. What’s good about
hydroelectric dams?
• 1. provides a clean (renewable) energy resource
• 2. provides a reservoir of water upstream that can be used
for drinking or recreation
• 3. can control flooding downstream
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https://upload.wikimedia.org/wikipedia/commons/thumb/6/6e/Ren2008.svg/800px-Ren2008.svg.png

4. What’s bad about
hydroelectric dams?
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f3d1b99a743ffa4142d9d7f1978d9686.ssl.cf2.rackcdn.com/files/22173/width754/2bhnjn4s-1365397320.jpg
1. slows the flow of water
downstream, which can limit
water for irrigation
2. habitats upstream are
destroyed (including some
towns)
3. reducing the amount of
water downstream can
destroy other habitats and
damage them so much that
animals die
https://www.internationalrivers.org/sites/default/files/sty
les/left/public/images/blog_entry/aviva_imhof/dead_fish.
jpg?itok=EXV0hIwV

5. Some dams have outlived their usefulness. Restore
the river to its wild state so that wildlife can benefit
from natural habitat.
• There are tens of thousands of dams around the
country that no longer serve the purpose they were
built to provide and whose removal could eliminate
the cost and liability associated with owning a dam.
Unless they are well maintained, their condition only
gets worse every year. The most cost-effective and
permanent way to deal with obsolete, unsafe dams is
to remove them. Just recently, Hurricane Matthew
caused widespread flooding and more than 20 dam
failures in North and South Carolina. Text from an article in
American Rivers Jessie Thomas-Blate | October 19, 2016
https://www.americanrivers.org/2016/10/removing-dams-can-save-lives/
https://www.yesmagazine.org/issues/water-
solutions/issue-54-images/beaver-photo-by-barbara-
hansen/image_mini
https://www.internationalrivers.org/sites/default/files/images/blog_e
ntry/Sarah%20Bardeen/livingrivershpf.jpg
https://upload.wikimedia.org/wikipedia/commons/thumb/b/bc/Wilson_Creek-27527-1.jpg/1200px-Wilson_Creek-27527-1.jpg

6. Undo the damage when you can:
restore the wild river.
• Often a dam is removed in order to undo the multiple detrimental
impacts it has on the environment and biodiversity. Dams divert water
from rivers for power, reducing the supply of water available to keep
downstream ecosystems healthy. Dams obstruct the migration of fish
and wildlife; for example, the U.S. Fish and Wildlife Service estimates
that 91% of the migratory fish habitat in northern New England is
blocked by dams. Dams also prevent nutrient rich sediments and woody
debris needed for habitats from flowing downstream. Dams slow the flow
of rivers, which allows sediment to collect on the river bottom and bury
spawning habitat. The slowed flow also disorients fish species whose
lifecycles evolved to take advantage of the swiftness and natural
seasonal variations of a river’s flow. The warmer temperature of
reservoir water sitting behind a dam may discourage cool-water fish
species from reaching their upstream spawning habitat. Water that is
released from the bottom of the reservoir is much colder and contains
less oxygen than river water, which can affect the reproductive
processes of some fish species; and when water with decreased oxygen
is released, it can kill downstream fish. In addition, the creation of
reservoir lakes favors species better suited to lake-like conditions,
which often harm native fish species. The sediment and silt trapped by
dams can accumulate heavy metals and pollutants. And turbines at
hydropower dams may injure fish.
https://blogs.ei.columbia.edu/wp-content/uploads/2011/08/Elwha_River_5144-300x200.jpg
https://blogs.ei.columbia.edu/wp-content/uploads/2011/08/Briggsville_Green-MA-600x450.jpg

7. Removing Dams
• Dams can age and begin to be
structurally unsound. That makes them
dangerous to all of the people, farms and
animals downstream.
• In some areas, new sources of power
such as solar and wind power make the
dam unnecessary and it can be removed.
• Removing the dam can allow new
habitats to establish along the new river
boundaries and wetlands.
https://upload.wikimedia.org/wikipedia/commons/b/b3/Dam_removal.jpg https://www.internationalrivers.org/sites/default/files/images/resourc
e/candace_lazarou/glines_smaller.jpg
https://www.internationalrivers.org/sites/default/files/images/campai
gn/admin-old/000107.jpg
https://natureconservancy-
h.assetsadobe.com/is/image/content/dam/tnc/nature/en/photos/3G8A
2160_4000x2200.jpg?crop=0,0,4000,2200&wid=4000&hei=2200&scl=1.0

8. Hydroelectric dam
• A dam is any retaining structure, built across a river to stop or regulate its
flow, and to raise the water level. Once a dam is built, water accumulates
behind it to form a lake or dam reservoir. Thus it also includes containment
structures for a large or small body of impounded water.
• While dams are built to stop flooding and facilitate shipping, they may
also be intended to generate electricity, and these are called hydroelectric
dams. Such a structure is an essential part of a hydroelectric project.
https://www.azocleantech.com/article.aspx?ArticleID=737
https://www.appropedia.org/File:Typicalplant.gifhttps://en.wikipedia.org/wiki/Hydropower#/media/File:The_Dam_(2890371280).jpg

9. Reservoir
• A reservoir is an artificial lake
where water is stored. Most
reservoirs are formed by constructing
dams across rivers. A reservoir can
also be formed from a natural lake
whose outlet has been dammed to
control the water level. The dam
controls the amount of water that
flows out of the reservoir.
(source: http://www.visitlakenorman.org/things-to-do/)
https://en.m.wikipedia.org/wiki/Cowans_Ford_Hydroelectric_Station#/media/File%3ADuke_Power'
s_Cowans_Ford_Dam.jpg

10. Dams help with flood
control downriver
• Hydroelectric plants can be put into
operation quickly. Their power output is
easily adjusted. Their operation remains
efficient whether for a short or long
period. Construction costs are low for
small or medium-sized dams compared
with other hydropower plants. A dam
produces electricity without burning fossil
fuels and is thus considered a source of
clean energy.
https://www.azocleantech.com/article.as
px?ArticleID=737
https://upload.wikimedia.org/wikipedia/commons/thumb/0/08/French
_Broad_River_flood_plain_as_viewed_from_Asheville_-_NARA_-
_281084.tif/lossy-page1-220px-
French_Broad_River_flood_plain_as_viewed_from_Asheville_-_NARA_-
_281084.tif.jpg
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tt_Jordan_Lake_Map.png/220px-B._Everett_Jordan_Lake_Map.png
https://upload.wikimedia.org/wikipedia/commons/thumb/c/c4/Cata
wbaRiver.jpg/300px-CatawbaRiver.jpg
https://upload.wikimedia.org/wikipedia/commons/thumb/6/63/Little_T
ennessee_River_%285149475130%29.jpg/512px-
Little_Tennessee_River_%285149475130%29.jpg

11. River Habitats in
North Carolina
• Wetlands are wet areas commonly referred
to as swamps, lowlands, marshes, bottomlands,
and sloughs (sounds like ‘slews’) and are the
most abundant coastal habitat type in North
Carolina. These areas have plants
and animals that are adapted to live parts of
their lives in water.
http://portal.ncdenr.org/web/mf/habitat/wetlands
https://www.tinrooflife.com/wp-
content/uploads/2018/05/Smoky-Mountains-Crabtree-Waterfall-
North-Carolina-1160x653.jpg
https://farm1.staticflickr.com/220/1517935010_899e8000fb_z.jpg
http://www.telapost.com/wp-content/uploads/2014/03/watauga1.jpg
https://upload.wikimedia.org/wikipedia/commons/thumb/c/c6/North_Caroli
na_River.jpg/170px-North_Carolina_River.jpg

12. River Habitat Residents
• Top left: a queen snake
• Top right: deer
• Bottom left: a North Carolina river
• Bottom right: a red wolf
https://upload.wikimedia.org/wikipedia/commons/thumb/c/c6/N
orth_Carolina_River.jpg/170px-North_Carolina_River.jpg
https://upload.wikimedia.org/wikipedia/commons/e/e4/NC_Deer.jpg
https://c1.staticflickr.com/1/26/98907978_cf91b8d244
.jpg
https://upload.wikimedia.org/wikipedia/commons/a/ac/07-03-
23RedWolfAlbanyGAChehaw.jpg

13. Use less water
• Water for domestic uses such as
flushing toilets, washing clothes, and
washing dishes can also be reduced by
certain conservation efforts. By installing
low - flow toilets and shower heads as
well as using washing machines and
dishwashers with water saving features,
humans can conserve water
http://4.bp.blogspot.com/-WjAtxld-
5G4/UKMGlnvAwnI/AAAAAAAANs8/vI7ZagaTPZs/s1600/Water
Savers%2BLogo.jpg
https://www.onecommunityglobal.org/wp-
content/uploads/2013/10/Nexus-Shower-Head-by-
Toto.png
http://2.bp.blogspot.com/-
v9h4JcQggIU/UETi4oFJWVI/AAAAAAABNE8/x41AIu65CoU/s
http://www.rootsimple.com/wp-
content/uploads/2015/06/Screen-shot-2015-06-03-at-
7.10.24-PM1.png

14. Conservation of Water
Resources
• As the human population grows, there will be a
greater need for clean water.
• Most water for drinking comes from surface or
groundwater freshwater resources, but with the growing
population, the need for drinking water is
increasing. Because of this many areas are looking into
the idea of desalination. This is the process of removing
the salt from saltwater resources, such as the ocean, so
that it can be used for drinking. Although most of the
water on Earth is saltwater, this process can be expensive
and it causes some pollution issues as well.
https://www.e-education.psu.edu/earth111/sites/www.e-
education.psu.edu.earth111/files/Module10/TampaBayDesalinationPlantProcess_HR.jpe
g
https://s3-us-west-2.amazonaws.com/courses-images-archive-read-only/wp-
content/uploads/sites/459/2015/06/21062634/Fig_12_3_2_5.jpg

15. Taking fresh water from the sea? What? How? Image left: Desalination plant
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70008832578/master/w_2560%2Cc_limit/SCIENC
E_Desalination_TA-486355798.jpg
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c0008301af7/master/w_1600%2Cc_limit/asset1-
Desalination-Facilities-and-Capacity_1-s2.0-
S0048969718349167-gr3_lrg_FINAL_web.jpg
There are two types of desalination—thermal, which heats up
water and then captures the condensation, and reverse osmosis,
which forces sea water through the pores of a membrane that are
many times smaller than the diameter of a human hair. This traps
salt molecules, but allows the smaller water molecules to go
through. Both require a great deal of energy, and greenhouse gas
emissions created by the power needed—especially in the Middle
East, where fossil fuels generate electricity—are a significant
contributor to global warming.
There are ecological impacts as well. It takes two gallons of
sea water to make a gallon of fresh water, which means the
gallon left behind is briny. It is disposed of by returning it to
the ocean and—if not done properly by diffusing it over
large areas—can deplete the ocean of oxygen and have
negative impacts on sea life.
A study by the UN Institute for Water, Environment and
Health published earlier this year contends that the problem
of brine waste has been underestimated by 50 percent and
that, when mixed with the chemicals meant to keep systems
from fouling, the brine is toxic and causes serious pollution.
Another problem comes from the sucking in of sea water for
processing. When a fish or other large organism gets stuck
on the intake screen, it dies or is injured; in addition, fish
larvae, eggs and plankton get sucked into the system and
are killed.
Wired: IM ROBBINS, SCIENCE 06.27.2019 09:00 AM
https://www.wired.com/story/desalination-is-booming-as-cities-
run-out-of-water/

16. Waste not want not
• Imagine that you are going to hike for a whole
summer day. You know that there are streams you will
pass, but that the water is famously polluted and
dangerous to drink. You must avoid becoming
dehydrated, so you carry a canteen that holds just
enough water for a person of your size, for one day. Do
you:
• Drink a little at a time throughout the entire hike
being careful not to spill any water.
• Guzzle as much as you like until the water runs out
and then just do without.
• Run out of water due to overuse and then take a
chance on drinking polluted water.
• Carry a water purifying kit and hope that it works on
the polluted water if you drink it.
https://upload.wikimedia.org/wikipedia/commons/5/55/McKinley_and_a_hiker.jpg
https://www.publicdomainpictures.net/pictures/240000/velka/water-canteen.jpg

17. Gulf coastal waters once were a fisherman’s
paradise, but now there are Dead Zones
https://oceantoday.noaa.gov/happennowdeadzone2011/otkn_409_happnow_deadzone_web_1280.jpg
According to NOAA, the Mississippi River
receives runoff from much of the nation and
that flows south to the Gulf of Mexico. But it
is this agricultural run-off combined with
urban run-off that brings excessive amounts
of nutrients into the Mississippi River and
starts a chain of events in the Gulf that ends
deadly. These nutrients fuel large algal
blooms that then sink, decompose, and
deplete the water of oxygen. This is Hypoxia
– when oxygen in the water is so low it can
no longer sustain marine life in bottom or
near bottom waters – literally a dead zone.
When the water reaches this hypoxic state,
fish and shrimp leave the area and anything
that can’t escape like crabs, snails, and
starfish die. So, the very fertilizers that are
helping our crops are disrupting the food
chain and devastating our food sources in the
ocean. ( HAPPENING NOW: DEAD ZONE IN THE GULF 2011:
https://oceantoday.noaa.gov/happennowdeadzone2011/)
https://images.app.goo.gl/a1inwbyo3x6LGNou5

18. Choices
• We humans are increasing our population rapidly. We
have plenty of space and resources, but much of what was
once pristine and healthful water for our use has been
carelessly damaged to the point of being dangerous to our
health.
• Now, before it is too late, we must do two things, in order
to ensure a steady supply of safe water for ourselves and
future generations.
• First: stop all polluting activities individually.
• Second: become politically active and insist that our
legislators implement stronger runoff regulations for
agriculture and stop allowing big, rich corporations to inject
toxic wastes from their manufacturing into the ground,
where it poisons the water in the water table and in rivers
and the oceans.
https://c1.staticflickr.com/9/8243/8634377621_16c451c
215_z.jpg
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SaveOurWaterLogo.png
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mons/f/f8/Usstamp-save-our.jpg