August 2014
Environmental Science Ch # 15
WATER MANAGEMENT
Water Issues
Potable Water
Hydrologic Cycle
Storage (map)
Aquifers/ Aquiclude/ Aquitard/ Artesian Water
Human’s Impact on the Hydrologic Cycle.
Types of Water Use
Domestic , Problems/ Treatment
Agricultural, Irrigation/ costs
In Stream, Drawbacks
Industrial, Clean Water Act 1977,81, 87, 93.
Types of and sources of Water Pollution
Toxic, Bioaccumulate
Decaying Organic Material, Anaerobic Bacteria
Nutrients, excessive growth.
Sources of Water Pollution- Point vs non-point
Municipal , Es cheri chia coli/ Cryptosporidian
Agricultural, surface waters/ conservation buffer
Industrial
Thermal
Marine oil pollution. 50% Biodegradable; 20% evaporate; 14% recovered; 12%
settles, 3% move shoreward.
Ground Water Pollution Sources – Ag products, fuel tanks, septic tanks.
Water Use Planning
Problems with water Diversion, wild life disruption
Waste water Treatment. – Primary, Secondary and Tertiary/Ozone
Preserving Scenic Water Areas and Wild life habitats. US Fed Wild life and
Scenic Act 1968
Salinization
GW Mining
Salt water intrusion.
Global Prospectives
The Everglades/ Aral Sea/ Garden City, Kansas/ the Mediterranean/ Lake
Victoria
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WATER MANAGEMENT
15 – 1. Global Water Challenge
Rising Demands
Climate Change
No subsitutes
15 – 2. The Water Issue
Organisms can exist only where there is access to water.
Properties – Unique due to its molecules being Di- Polar. It causes other molecules to
separate. This makes it a solvent. It also has the ability to store heat. It heats and cools
more slowly than other substances. As a result its presence modifies the local climate.
70% of the planet’s surface is covered with water, of which 3% is potable - free of
dissolved salt, plant and animal wastes and bacterial contamination. Previously
believed to be inexhaustible.
UN reports that within this decade, all will experience water shortages, due to:
Droughts/ floods
Pollution
Increasing population demand.
30% of the world’s population does not have access to safe drinking water.
15 – 3. Hydrologic Cycle
All the water on earth is locked into a constant recycling process, due to energy
movement. Recycling called the Hydrologic cycle.
Evaporation – energy added
Precipitation as rain, snow or sleet - energy lost
Infiltration to the GW table or run-off.
Evapo-Transpiration - plant absorption and release
Water is stored in glaciers and aquifers naturally.
Unconfined aquifers are overlain by aquitards and WT. It is replenished by rain. The
Vadose zone/ zone of aeration/unsaturated zone lie above the aquitard.
Confined aquifers lie on an aquiclude. Replenished through recharge zones. Artesian
wells draw their water from confined aquifers, a function of pressure.
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15 – 4. Human Influence on the Hydrologic Cycle
Major impact -Land use – Irrigation/ Dam construction/ Cooling cause evaporation
Urban development affects run off.
Timber harvesting decreases evapo-transpiration
Cloud seeding causes precipitation.
15 – 5. Kinds of Water Use
Water use is measured by the amount of water withdrawn from the source, but not all
withdrawn water is consumed.
The water that is incorporated into a product or lost to evaporation is considered
consumed.
Water usage is classified into 4 categories:
 Domestic – source is private wells in the rural areas, and Purification facilities
in cities. 37% of the latter water comes from well.
o Uses- as a solvent and drink. Approx. 100 to 140 gals/day/person.
o Problems – demands exceed supply. Waste is 4X consumption.
o Public attitude is: a limitless resource. Can be corrected by increasing
cost.
Treatment involves filtering through sand and charcoal to remove
particles.
chemicals are added to remove dissolved matter.
It is disinfected (chlorine) to remove any organisms.
Ozone or UV radiation is used to remove any left over organisms
Desalinization is an option
* Cost is anticipated to increase due to greater population and the cost of
cleaning, distribution and education.

Agricultural – irrigation. GW supplies 40%, surface 60%. Irrigation makes
up 80% of the water consumed in the US. The amount used depends on cost/
crops/ product demand/ technology/ government policy. The types of
irrigation varies:
o Trickle – directly to roots
o Furrow – surface or flood
o Spray – overhead
o Sub irrigation – under ground pipes, which are also used to drain away
water
Drawback: Expensive, besides having a major impact on land values. Increase cost will
lead to conservation.
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
Industrial use – (accounts for >50% withdrawals in the US), for heat
exchange or to dissipate and transport waste. About 20% of the water used in
cooling is sea water.

In-stream use (water is not removed and there is no consumption.
o Hydroelectric power generation (13% of generation in the US).
Disadvantages: Construction costs, habitat destruction, nutrients trapped, evaporation,
fish migration hindrance, water quality degradation, and shoreline erosion.
Advantages: More recreation facilities
Navigation (dredging)/Transportation - requires sufficient water depth. Causes pollution.
The law prohibits discharge into surface water bodies without permit.
Federal Water Pollution Act 1948 provides funds and technical assistance to improve
water quality. Clean water Act 1977, 81, 87, & 93.
15 – 6. Kinds and Sources of Water Pollution.
Characteristics of Water Pollution.
To maintain completely unpolluted water is impossible.
Pollution occurs when something changes the natural ecosystem. Pollutants are
categorized as:
Toxic, which bio-accumulates. Unfit for human use.
Decaying organic matter causes major pollution in water because it uses up the oxygen
in the water. When O2 is used up, ANAEROBIC bacteria begin to break down waste,
produces chemicals responsible for the foul smell and bad taste.
BOD is the amount of oxygen required to decay a specific quantity of organic matter.
Nutrients are also a pollution problem. Nitrogen and phosphorus compounds, if added to
water will increase plant growth and algae. If no growth occurs, these nutrients are
limiting factors (in short supply).
Excessive growth causes eutrophication. Physical particles alter the clarity of the water.
Sources of Water pollution
Classified as: Point or non-point sources.
Municipal water pollution
Storm waters
Industrial wastes
Homes and commercial wastes: measured through the Es cheri chia Coli and
Streptococcus faecalis content. (derived from warm-blooded animals).
Detergent content is also a measure of pollution. One end of a soap molecule structure
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dissolves grease or dirt and the other end is dissolved in water.
Farm operations are the primary source of phosphates and Cryptosporidium..
Agricultural Water Pollution
Excessive fertilizer and pesticide and Agricultural chemicals pollute surface waters. The
use of a conservation buffer lessens the chances of pollution by runoff.
Industrial Water Pollution
Pollution results from organic matter and or petroleum products, toxic materials, metals,
acids, nutrients and particulates.
Industries are required to pre-treat waste before sending to the city sewage. Further more,
Point Sources are strictly regulated.
Mining waste (run off) is a unique source of pollution.
Thermal Pollution.
Returning hot water to its original source is not allowed, because it changes the habitat
conditions in the ecosystem. It can also prevent spawning, or alter the entire food web.
Industries use ponds to cool water before return, or use cooling towers, where the hot
water is sprayed into the atmosphere and is cooled by evaporation, or use Dry Towers, in
which the heated water is pumped through pipes and heat is released into the air.
Marine Oil Pollution.
Generally, 50% of oil is biodegradable, 20% evaporates, 14% is recovered, 12% settles
into the bottom sediments and 3% ends up on the shorelines.
There are many sources of pollution, but most result from:
Accidents
Runoff from streets
Improper disposal of oils
Intentional disposal of ballast
To control pollution, the following steps are normally taken:
Recycle or reprocess.
Regulations are enforced in refining and shipping operations
Ground Water Pollution Sources.
Potential sources span every aspect of social, agricultural, and industrial activity.
Agricultural products – accidental spills of pesticides, fertilizer applications and
irrigation practices.
Underground fuel storage tanks
Landfills – approximately 90% are not lined to EPA specifications
Septic tanks, which are poorly designed, contaminated by nitrate content.
Estimate > 20,000,000 are operating with about 30% improperly.
Surface impoundments (pits and ponds) >225,000 used.
Other possible sources are mining waste, road salt, open dumps, cemeteries,
radioactive waste disposal sites, feed lots and urban runoff.
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15 – 7. Water Use Planning Issues.
Metro areas provide three basic services
Supply for individual and industrial needs
Waste water collection and treatment
Storm waters collection and management.
Supply is obtained through wells and or surface bodies, which requires watershed
protection.
Major problems arise when handling storm water runoff. (Most cities must have facilities
to store the runoff until treatment is completed).
The following must be considered:
Increase demand, which will increase pressure for diversion projects.
Increase treatment of wastewater or Recycling existing water supply, both of
which increase costs.
Irrigation water quality, water being returned to source.
Groundwater mining
Salt water intrusion.
Increase demand for water based recreation.
Water Diversion, the physical process of transferring water from one area to another.
Examples include: Garrison Dam from the Missouri to the Red River.
Water moved from the Colorado River to LA.
Water moved from Penn. to NY.
Problems: Wildlife disruption, falling water level, Fish extinction.
Waste water treatment.
Primary: Physical - screens used to remove particles, followed by settling in
ponds.
Secondary: a biological process. Waste mixed with oxygen rich waters, held until
degraded by bacteria. Organic matter concentrates as large particles, and settles out as
sewage sludge. After dewatering, the waste is sold as fertilizer or sent to a landfill.
The discharged water is disinfected by chlorination, or chemically or with ozone or UV
light or Ultrasonic energy.
Tertiary: Chemicals used to remove dissolved pollutants such as: nitrates and
phosphates. The treated water is used to irrigate golf courses, or in wetlands.
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Salinization – Irrigation Water Quality.
An increase in salinity, resulting from salt concentration in the soil after irrigating
Example is the Colorado River is 20X more saline after irrigation up stream.
Ground water Mining.
When water is removed faster than it is replenished, the water table drops and settling
occurs. Examples include London, Mexico City, Houston, Las Vegas, San Joaquin
Valley, CA.
Saltwater intrusion results from GW mining. Example is Galveston.
Preserving Scenic water Areas and Wildlife Habitats – Increase demand for
recreation.
The US Fed Wild and Scenic Act 1968 established a system to protect from development.
Historically, wetlands were considered worthless, but recently its value as the breeding
ground and spawning areas has been recognized. Wetlands act as filters, slow and prevent
flooding and erosion.
Global Perspective.
Ganges River. Approx 300 Million live in its basin. Water is used to drink, wash,
dispose of waste, and bodies are cremated in it.
As a consequence of forest destruction, floods occur commonly. There are now health
problems, visual pollution, and snapping Turtles are introduced into the Ecosystem.
The Everglades. Originally, water drained from N- S. There was a constant flow. Park
was established in 1947. Since then land conversion to agriculture and urban
development occurred. The introduction of exotic biota and nutrients has cause additional
changes.
Congress passed a bill to restore it to its natural state at an introductory cost of $1.4 B.
Aral Sea. Located between Uzbekistan and Kazakhstan, it was once larger than all of the
Great Lakes, except Superior. Water was diverted south to Turkmenistan for cotton
production.
Since 1960, it has shrunk 75% by volume, 50% of surface area. The fishing industry was
destroyed (20 of 24 species are now extinct). Health problems resulted from the dust
(exposed beaches) erosion, water supplies are unsafe to drink and the climate has
changed.
Water is now pumped into the sea.
Garden City, Kansas. GW mining from the Ogallala fm.
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Prior to 1960, wheat was grown. It did not require much water. Corn is now grown and
there is an economic boom. Feed lots were established. WT level dropped 4 met.
Potential problems include: drop in land values, possibly another dust bowl, Diversion of
water.
Mediterranean Sea. More than 150 M live along the coastline and 300 M within the
basin. The nations have cultural differences and governments.
Findings: Hg in mammals up to 300 ppm (should be .05 ppm).
PCBs are 50X higher than acceptable limits
Pollutants include HC and pesticides.
Sea cannot purge itself due to geography quickly.
Toxic metals derived from Eastern Europe
Some cities have no wastewater treatment.
Lake Victoria. Borders Uganda, Kenya and Tanzania. It is the largest fresh water body
in Africa. It is now heavily populated with algae, and lilies. Fish population decreased
due to over fishing and introduction of exotic species. Nile perch is sold to Israel and
European nations. Bottom sediments indicate population growth is a major contributor.
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