Masai Mara
• http://www.cbsnews.com/videos/the-greatmigration-2/
GLOBAL WATER CRISIS
• Water - the essential ingredient for life on this planet – is becoming
an increasingly scarce resource. According to the World Bank and
World Health Organization, 2 billion people lack access to clean
water and 1 billion people do not have enough to even meet their
daily needs.
• Every day an increasing amount of pollution seeps into rivers and
lakes making them toxic to humans, and underground aquifers –
our most significant sources of water – are being depleted at an
alarming rate.
• By 2050 the number of people on the planet is projected to exceed
9 billion, and if current trends continue more and more useable
water will be lost. Making an adequate supply of water available to
everyone alive today is a monumental task, and ensuring that there
is enough water for all future generations will require
an unprecedented level of international cooperation and
compassion…
This picture shows the size of a sphere that would contain all of Earth's water in
comparison to the size of the Earth. The blue sphere sitting on the United States,
reaching from about Salt Lake City, Utah to Topeka, Kansas, has a diameter of
about 860 miles (about 1,385 kilometers) , with a volume of about 332,500,000
cubic miles (1,386,000,000 cubic kilometers). The sphere includes all the water in
the oceans, seas, ice caps, lakes and rivers as well as groundwater, atmospheric
water, and even the water in you, your dog, and your tomato plant.
Water’s Importance, Availability and
Renewal
Our liquid planet glows like a soft blue sapphire in the
hard-edged darkness of space. There is nothing else like it
in the solar system. It is because of water.
John Todd
https://www.youtube.com/watch?v=Q54a4PCV9Ac
https://www.youtube.com/watch?v=VIaw5mCjHPI
Why is water so important-lifeblood of ecosystem
Many Properties Related to
Polarity-Strong Hydrogen Bonding
Aquifer: groundwater exists in the multitude of small spaces
found within permeable layers of rock and sediment.
Unconfined: water can flow in and out
Confined: impermeable layer of rock or clay impedes water
flow to or from the aquifer
Water Table: uppermost level of ground water; dynamic
Groundwater withdraw/mining: removal of water for
agriculture and municipal use.
Wells-Cone of Depression: drilling to aquifer to tap water
supply; if overpumped can cause near by wells to go dry.
Recharge: water from precipitation can percolate through soil
and replace water that has been withdrawn.
• To reach an aquifer, surface water must travel down through permeable
layers of soil and rock. Water cannot reach an aquifer from places
where the aquifer is covered by impermeable materials.
• The recharge zone is an area in which water travels downward to
become part of an aquifer.
• Recharge zones are environmentally sensitive areas because any
pollution in the recharge zone can also enter the aquifer.
• The size of an aquifer’s recharge zone is affected by the permeability of
the surface above the aquifer.
• Structures such as buildings and parking lots can act as impermeable
layers and reduce the amount of water entering an aquifer.
• Communities should carefully manage recharge zones, because surface
water can take a very long time to refill an aquifer, even tens of
thousands of years.
 We do not know much about ground water pollution
because it is difficult to track and test aquifer water quality.
Groundwater cannot cleanse itself well (moves slowly/less
oxygen/colder)
 Underground leaking tanks are biggest threat
 MTBE-methyl tertiary butyl ether-a gasoline additive, not
used since 1979 is still present in groundwater plumes that
move through aquifers.
 Pharmaceuticals: prescription medicines and personal care
products (hormone replacement, painkillers, chemotherapy
drugs) are flushed or land-filled and leach into groundwater
 Arsenic
 Saltwater intrusion
 Groundwater contamination must be prevented
Diseases Transmitted through Contaminated Drinking
Water
Type of Organism
Disease
Effects
Bacteria
Typhoid Fever, Cholera
Diarrhea, vomiting,
dehydration, fatal if
untreated
Viruses
Hepatitis B
Fever, Headache,
abdominal pain,
jaundice, enlarged liver
Parasitic Protozoa
Amoebic dysentery,
giardiasis,
Severe diarrhea,
headache, abdominal
pain, could be fatal
Parasitic worms
Schistosomiasis
Abdominal pain, rash,
fatigue, ill health
•
Causes/Problems: Developed Countries
Ex. Cuyahahoga River in Ohio
http://www.youtube.com/watch?v=tZA9OX2joUc
• Developing Countries
Ex. Ganges River in India
http://www.youtube.com/watch?v=wb_yDBmRgm
U
https://www.youtube.com/watch?v=B8nMr0GZWp
A
Central China
EPA’s definition
• Nonpoint source pollution generally results from land runoff, precipitation,
atmospheric deposition, drainage, seepage or hydrologic modification.
The term "nonpoint source" is defined to mean any source of water
pollution that does not meet the legal definition of "point source" in
section 502(14) of the Clean Water Act. That definition states:
• The term "point source" means any discernible, confined and discrete
conveyance, including but not limited to any pipe, ditch, channel, tunnel,
conduit, well, discrete fissure, container, rolling stock, concentrated animal
feeding operation, or vessel or other floating craft, from which pollutants
are or may be discharged. This term does not include agricultural storm
water discharges and return flows from irrigated agriculture.
• Unlike pollution from industrial and sewage treatment plants, nonpoint
source (NPS) pollution comes from many diffuse sources. NPS pollution is
caused by rainfall or snowmelt moving over and through the ground. As
the runoff moves, it picks up and carries away natural and human-made
pollutants, finally depositing them into lakes, rivers, wetlands, coastal
waters and ground waters.
• Ocean water is also polluted by accidental oil
spills. Each year, about 37 million gallons of oil
from tanker accidents are spilled into the ocean.
• Such oil spills have dramatic effects, but they are
responsible for only about 5 percent of oil
pollution in the oceans. Most of the oil that
pollutes the oceans comes from cities and towns.
• Limiting these nonpoint-sources of pollution
would go a long way toward keeping the oceans
clean.
• Water pollution can cause immediate damage to
an ecosystem, but the effects can be far reaching
as some pollutants build up in the environment
because they do not decompose quickly.
• Biomagnification is the accumulation of
pollutants at successive levels of the food chain.
• Biomagnification has alarming consequences for
organisms at the top of the food chain, and is one
reason why U.S. states limit the amount of fish
people can eat from certain bodies of water.
• The Clean Water Act of 1972 was to designed to
“restore and maintain the chemical, physical, and
biological integrity of the nation’s waters.”
• The goal-making all surface water clean enough
for fishing and swimming by 1983 was never
achieved, but much progress has been made
since the act was passed.
• The percentage of lakes that are fit for swimming
has increased by 30 percent, and many states
have passed stricter water-quality standards.
Most water must first be made potable.
Potable means suitable for drinking.
Water treatment removes elements such as mercury, arsenic,
and lead, which are poisonous to humans even in low
concentrations.
These elements are found in polluted water, but they can also
occur naturally in groundwater.
A pathogen is a virus, microorganism, or other substance that
causes disease.
Pathogens are found in water contaminated by sewage or
animal feces, but can be removed with water treatment.
There are several methods of treating water to make it
potable. A common method includes both physical and
chemical treatment.
• The problem of sewage sludge disposal has
prompted many communities to look for
new uses for this waste.
• If the toxicity of sludge can be reduced to
safe levels, it can be used as a fertilizer.
• In another process, sludge is combined
with clay to make bricks that can be used
in buildings.
City of Woodburn-Oregon
•
The wastewater treatment plant provides primary, secondary, and tertiary
treatment along with effluent reuse. Treated effluent is either discharged to the
Pudding River or irrigated to a poplar tree reuse system. The City provides
secondary wastewater treatment from November 1 to April 30 and tertiary
treatment with reuse from May 1 to October 31, depending on receiving stream
flow.
Combined Sewer Overflows (CSO)
• http://water.epa.gov/polwaste/npdes/cso/ind
ex.cfm
• Agriculture accounts for 67 percent of the
water used in the world. Plants require a lot of
water to grow, and as much as 80 percent of
the water used in agriculture evaporates.
• To supply dry regions with water, all or part of a
river can be diverted into canals that carry water
across great distances.
• The Colorado River begins as a glacial stream in
the Rocky Mountains and quickly grows larger as
other streams feed into it. As the river flows
south, it is divided to meet the needs of 7 states.
• So much of the river’s water is diverted for
irrigation and drinking water that the river runs
dry before it reaches the Gulf of California.
The river provides water to irrigate crops (pistachio trees in Arizona seen in this photo);
70% of the river is drawn off to irrigate 3.5 million acres of cropland.
• http://www.npr.org/2014/05/06/309101579/
drought-stricken-texas-town-turns-to-toiletsfor-water
• As water sources become depleted, water becomes more expensive.
• This is because wells must be dug deeper, water must be piped greater
distances, and polluted water must be cleaned up before it can be used.
• Water Conservation is one way that we can help ensure that everyone will
have enough water at a reasonable price.
•
Desalination is the process of removing salt from ocean water.
• Some countries in drier parts of the world, such as the Middle East, have
built desalination plants to provide fresh water. Most desalination plants
heat salt water and collect the fresh water that evaporates.
• Because desalination consumes a lot of energy, the process is too
expensive for many nations to consider.
What makes water saline?
What is meant by "saline water?" Water that is saline contains
significant amounts (referred to as "concentrations") of dissolved salts.
In this case, the concentration is the amount (by weight) of salt in
water, as expressed in "parts per million" (ppm). If water has a
concentration of 10,000 ppm of dissolved salts, then one percent of
the weight of the water comes from dissolved salts.
Here are parameters for saline water:
• Fresh water - Less than 1,000 ppm
• Slightly saline water - From 1,000 ppm to 3,000 ppm
• Moderately saline water - From 3,000 ppm to 10,000 ppm
• Highly saline water - From 10,000 ppm to 35,000 ppm
• By the way, ocean water contains about 35,000 ppm of salt.
Your own personal desalination plant
https://www.youtube.com/watch?v=qZ5ut_4zKug