Water Quality and Usage

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Water Quality and Usage

• Lecture 11
• GLY 120

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• Water is absolutely necessary to life and to all
  aspects of human use of the land
• As a result, water resources are probably the
  most legislated and discussed commodity in the
  area of environmental law

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Water Quality

• Water quality can be thought of as
• a measure of the suitability of water for a
  particular use
• based on selected physical, chemical, and
  biological characteristics
• Standards and guidelines are established to
  protect water for designated uses such as
• Drinking
• Recreation
• Agricultural irrigation
• Protection and maintenance of aquatic life
• Standards for drinking-water quality ensure that
  public drinking-water supplies are as safe as
  possible

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Water Quality Criteria

• Water quality criteria are developed by
  scientists and provide basic scientific
  information about the effects of water pollutants
  on a specific water use
• Are based on variables that characterize
• the quality of water
• and/or the quality of
• the suspended particulate matter
• the bottom sediment
• and the biota

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• Many water quality criteria set a maximum level
  for the concentration of a substance in a
  particular medium (i.e. water, sediment, or
  biota) which will not be harmful when the
  specific medium is used continuously for a
  single, specific purpose
• For some other water quality variables, such as
  dissolved oxygen, water quality criteria are set
  at the minimum acceptable concentration to ensure
  the maintenance of biological functions

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• Water quality criteria often serve as a baseline
  for establishing water quality objectives in
  conjunction with information on water uses and
  site-specific factors
• Water quality objectives aim at
• supporting and protecting designated uses of
  freshwater
• while supporting and maintaining aquatic life
  and/or the functioning of aquatic ecosystems

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• The establishment of water quality objectives is
  not a scientific task but rather a political
  process that requires a critical assessment of
  national priorities.
• Such an assessment is based on
• economic considerations
• present and future water uses
• forecasts for
• industrial progress
• the development of agriculture
• many other socio-economic factors

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• Targets to improve water quality are usually set
  at two levels.
• The first represents the ultimate goal at which
• no adverse effects on the considered human uses
  of the water would occur
• the functions of the aquatic ecosystems would be
  maintained and/or protected

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• A second level is defined as a water quality
  target that should be reached within a fixed
  period of time.
• This level is a result of a balance between
• what is desirable from an environmental point of
  view
• what is feasible from an economic and technical
  point of view.
• This second level allows for a step-by-step
  approach that finally leads to the first level

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• Natural water quality varies from place to place,
  with the seasons, with climate, and with the
  types of soils and rocks through which water
  moves
• When water from rain or snow moves over the land
  and through the ground, the water may
• dissolve minerals in rocks and soil
• percolate through organic material such as roots
  and leaves
• react with algae, bacteria, and other microscopic
  organisms

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• When water evaporates from lakes and streams,
  dissolved minerals are more concentrated in the
  water that remains.
• Each of these natural processes changes the water
  quality and potentially the water use.
• In general, the common constituents are not
  considered harmful to human health
• although some constituents can affect the taste,
  smell, or clarity of water

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What is naturally in the water?

• The most common dissolved substances in water are
  minerals or salts that, as a group, are referred
  to as dissolved solids
• Dissolved solids include
• common constituents such as
• Calcium
• Sodium
• Bicarbonate
• Chloride
• plant nutrients such as
• Nitrogen
• Phosphorus
• trace elements such as
• Selenium
• Chromium
• Arsenic

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• Earths waters range widely in composition and in
  suitability for human usage
• The most pure spring or rainwaters may have as
  little as 30 ppm (0.003) of minerals
• Most saline waters may have nearly 300,000 ppm
  (30) dissolved substances
• In general, waters with more than 500 ppm (0.05)
  dissolved salts are unsuitable for human
  consumption
• Waters with more than 2000 ppm (0.2) dissolved
  solids are unsuitable for most other human uses

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Federal Water Legislation

• The federal government has long recognized the
  need to protect water resources from pollution
• The ultimate goal of the legislation is to
  protect our water supply as well as the natural
  environment

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• Significant federal legislation includes
• Federal Water and Pollution Control Act of 1956
• This legislation had the objective of
• enhancing the quality of water resources
• and preventing, controlling, and abating water
  pollution
• Water Quality Improvement Act of 1970
• This legislation
• expanded the power of the 1956 Act through
  control of oil pollution and hazardous pollutants
• established research and development to eliminate
  acid mine drainage and pollution in the Great
  Lakes

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• Federal Water Pollution Control Act Amendments of
  1972
• Also known as the Clean Water Act
• The primary purpose of this legislation was to
  clean up the nations waters
• Provided billions of dollars in federal grants
  for sewage treatment plants while encouraging
  innovative technology including alternative water
  treatment methods
• Has resulted in tremendous improvement of water
  quality in the US

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• Comprehensive Environmental Response,
  Compensation, and Liability Act of 1980
• Established the so-called Superfund to clean up
  hazardous waste disposal sites, reducing
  groundwater pollution
• Hazardous and Solid Waste Amendments to the
  Resource Conservation and Recovery Act of 1984
• Regulates underground storage tanks, thus
  reducing potential for gasoline and other liquid
  pollutants to damage groundwater resources

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Water Use
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Surface Water Laws

• Riparian Doctrine
• Prior Appropriation Doctrine

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• Riparian Doctrine
• Prevailing water law in most states prior to 1850
• Still used in most of the eastern half of the US
• Riparian rights to water are restricted for the
  most part to owners of the land adjoining a
  stream or body of standing water

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• It is important to understand that a water right
  is not a legal title to the water
• It is simply the legal right to use water in a
  manner dictated by law
• Under the Riparian Doctrine, the right to use
  water is considered real property
• But, the water itself does not belong to the
  property owner

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• Riparian water rights are considered property
  that enters into the value of the land and may be
  transferred, sold, or granted to other people
• Landowners have the right to
• make reasonable use of water on their land,
  provided the water is returned to its natural
  stream before it leaves the property
• receive full flow of the stream undiminished in
  quantity and quality
• But the property owner is not entitled to make
  withdrawals of water that infringe upon the
  rights of other riparian owners

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• Prior Appropriation Doctrine
• Holds that prior usage is a significant factor
• That is, the first person to divert water and use
  water from a surface water supply has the primary
  right and this may be passed on to successive
  owners
• Furthermore, the right to use water is separate
  from other property rights
• Appropriation water law is common in the western
  part of the US

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Groundwater Law

• Absolute Ownership Doctrine
• Reasonable Use Doctrine
• Correlative Rights Doctrine

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Groundwater Law

• Absolute Ownership Doctrine
• In the US, laws governing groundwater use go back
  to the right of absolute ownership of the water
  beneath a particular persons land
• Under this doctrine landowners could pump at will
  and take as much water as they wished
• Even though that water was shared in a common
  groundwater aquifer with adjacent landowners

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• This type of arrangement works pretty well in a
  region with a wet, humid climate such as the
  eastern US, where there is usually plenty of
  water
• However, even in these areas, problems may arise
  during drought conditions

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• Reasonable Use Doctrine
• The amount of groundwater withdrawn is based upon
  the reasonable and beneficial purposes the water
  is used for on the land above the aquifer
• Used mainly in the western US
• Problems arise from
• Establishing what is reasonable
• The fact that the doctrine is applied through a
  system of laws regulating the issuing of pumping
  permits

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• Correlative Rights Doctrine
• Developed in California
• Recognizes a landowners right to use water
  beneath the land
• Limits these rights by making provisions for
  other landowners whose property overlies a common
  groundwater source
• All of the landowners have equal or correlative
  rights to a reasonable amount of groundwater when
  the water is applied to beneficial use of the
  land over the groundwater aquifer

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• Water is more widely used and more essential than
  any other resource
• The amount consumed per capita varies widely as a
  function of each societys lifestyle and standard
  of living

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Water Use

• Water is more widely used and more essential than
  any other resource
• The amount consumed per capita varies widely as a
  function of each societys lifestyle and standard
  of living

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• Definition of water usage terms
• Withdrawal
• The water physically extracted from its sources
• Consumption
• The withdrawn water that is no longer available
  because it has been
• evaporated,
• transpired,
• incorporated into products or crops,
• consumed by humans or livestock,
• or otherwise held from returning to its source

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• Offstream uses
• Remove or divert water from its source
• Examples include water for
• Irrigation
• Livestock
• Thermoelectric power generation
• Industrial processes
• Public supply
• Consumptive use is an offstream use

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• Instream uses
• Relates to the water that is used but not
  withdrawn from its source
• Examples include use of river water for
• Navigation
• Hydroelectric power generation
• Fish and wildlife habitat
• Recreation

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• Total water usage in the US
• In 2000, the total water usage was 5481 L (1448
  gal) per person per day for all usages
• Total water use in the US has been declining
  since 1975
• Due to
• Efficiency and conservation efforts
• Technological and economic changes

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• But the bad news is that pumping of groundwater
  has increased.
• In too many places the underground aquifers are
  already over stressed.
• Although groundwater is an important source of
  water
• It is not unlimited
• And it is not being used responsibly

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• Movement of Water to People
• In our modern civilization, water is often moved
  vast distances from areas with abundant rainfall
  to areas of high usage
• In California, demands are being made on northern
  rivers for reservoir systems supplying the cities
  in the southern part of the state
• 2/3 of Californias runoff occurs north of San
  Francisco, where there is a surplus of water
• 2/3 of Californias water use occurs south of San
  Francisco, where there is a deficit of water

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Types of Water Usage

• Irrigation
• Agriculture is a major user of ground and surface
  water in the US
• Accounts for 80 of the nations consumptive
  water use
• Accounts for over 90 in many western states
• Irrigated agriculture remains the dominant use of
  fresh water in the US
• although irrigations share of total consumptive
  use has declined since 1970

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• Water management is an important element of
  irrigated crop production
• Efficient irrigation systems and water management
  practices can
• help maintain farm profitability
• reduce the impact of irrigated production of
  offsite water quantity and quality

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• Industry and Mining
• Water is said to be the lifeblood of industry
• It is used as
• a raw material
• as a coolant
• a solvent
• a transport agent
• and as a source of energy
• For example, an automobile coming off the
  assembly line will have used at least 120,000 L
  of water
• 80,000 L to produce the steel
• 40,000 L more for the actual fabrication process
• Many thousands more liters of water are involved
  in the manufacture of its plastic, glass, and
  fabric components

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• Industrial water use includes water for such
  purposes as processing, washing, and cooling in
  facilities that manufacture products
• Major water-using industries include, but are not
  limited to
• Steel
• Chemical and allied products
• Paper and allied products
• Petroleum refining

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• For the year 2000, withdrawals were an estimated
  19,700 Mgal/d
• Industrial withdrawals were about 5 of total
  withdrawals
• Surface water was the source for 82 of total
  industrial withdrawals

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• Mining
• Mining water use is classified as water used for
  extraction of minerals that may be in the form of
• Solids such as coal, iron, and gravel
• Liquids such as crude petroleum
• Gases such as natural gas
• For 2000, withdrawals were an estimated 3,490
  Mgal/d
• Mining withdrawals were nearly 1 of total
  withdrawals
• Groundwater was the source of 58 of total
  withdrawals for mining

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• Thermoelectric Power
• Water for thermoelectric power is used in
  generating electricity with steam-driven turbine
  generators
• The total quantity of water withdrawn for
  thermoelectric power in 2000 was an estimated
  195,000 Mgal/d
• Thermoelectric power withdrawals accounted for
  48 of total water use
• Surface water was the source for more than 99 of
  total thermoelectric power withdrawals

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• Hydroelectric Power
• Hydroelectric energy is produced by the force of
  falling water
• A dam holds back water, creating a reservoir of
  potential power
• On the upper side of the dam, a gate is opened to
  let water surge through a tunnel leading to
  turbines
• The water turns the turbines which in turn spin
  generators to generate electricity
• The electricity is carried through cables to
  wherever its needed
• Water uses for hydroelectric purposes in 2000
  were 3,290,000 Mgal/d
• Hydroelectric power uses water instream is not
  included in total water withdrawal data

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• Trends in Water Use
• Instream surface water use far exceeds offstream
  uses
• A tremendous amount of water is used in the
  stream environment to
• Generate electricity
• Provide for navigation and recreation
• Ensure fish and wildlife habitat

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• Both instream and offstream water uses increased
  until approximately 1975, and since then these
  uses have leveled off
• Better water management and conservation has
  happened over the last 30 years

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• Irrigation needs and the thermoelectric industry
  are the big users of fresh water
• Use of water by the public has increased steadily
  through the period
• A trend presumably related to the steady increase
  in population of the country
• The use of water by agriculture for irrigation
  leveled off in 1975 and has decreased slightly
  since then
• Presumably related to efforts in water
  conservation

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• Industry, since 1980, has used significantly less
  fresh water
• This is due, in part, to
• New technologies that require less water
• Improved plant efficiencies and increased water
  recycling

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• Trends from 1950-20000 for freshwater withdrawals
  by water-use category

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Water Conservation

• What can be done to use water more efficiently
  and reduce withdrawal and consumption?
• Improved agricultural irrigation could reduce
  withdrawals by between 20-30
• Such improvements include
• Lined and covered canals that reduce seepage and
  evaporation
• Computer monitoring and scheduling of water
  releases from canals
• A more integrated use of surface water and
  groundwater
• Not irrigating during the heat of the day
• Improved irrigation systems
• Better land preparation for water application

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• Withdrawal of water for domestic use may be
  substantially reduced at a relatively small cost
  with
• More efficient bathroom and sink fixtures
• Not watering lawns during the heat of the day
• Drip irrigation systems for domestic plants

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• How people perceive the water supply is important
  in determining how water is used
• People in Tucson, AZ, perceive the area as a
  desert
• Cultivate many native plants such as cactus in
  their yards
• Water use is 605 L (160 gal) per person per day
• People in Phoenix, AZ, have been accused of
  having an oasis mentality
• Have large lawns, mulberry trees, and high hedges
• Use as much as 3780 L (1000 gal) per person per
  day

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• Water rates also make a difference
• People in Tucson pay 75 more for water than do
  people in Phoenix, where the water supply is
  drawn from the Salt River rather than from
  groundwater (as it is in Tucson)
• Water removal for steam generation of electricity
  could be reduced as much as 25-30 by using
  cooling towers designed to use less or no water
• Manufacturing and industry might curb water
  withdrawals by
• Increasing in-plant treatment and recycling water
• Developing new equipment and processes that
  require less water

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• Groundwater is among the nations most important
  natural resources
• It is the source of drinking water to more than
  140 million residents
• or about half of the nations population
• It is the primary source of drinking water for
• nearly all of the rural populations
• as well as for some of our largest metropolitan
  areas

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• Nearly 50 billion gallons of groundwater are used
  each day in support of the nations agricultural
  economy
• The increasing hydrologic stresses and competing
  demands on our groundwater resources are making
  groundwater management increasingly complex

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• Water resource management needs a new philosophy
  that
• considers geologic, geographic, and climatic
  factors
• and utilizes creative alternatives