Water Resources and Management

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Water Resources and Management

• GEOG 4350
• Instructor Michael Lee Ph.D.

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A Key Resource

• Water is essential for cities, for irrigation,
  for industry, for recreational use, and for our
  environment.
• There isn't enough water for everyone - it
  doesn't occur universally in the quantity and
  quality that everyone needs.
• Water delivery systems are often prohibitively
  expensive, and access to water sources is
  becoming increasingly difficult for millions.

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Global Water

• Some 315,000,000 cubic miles (95) is seawater
• Some 9,000,000 cubic miles (2.5) is in aquifers
  deep below the earth's surface
• Some 7,000,000 cubic miles (2) is frozen in
  polar ice caps
• Potentially exploitable surface freshwater
  resources make up about 0.027 of all the water
  on our planet.

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Water, Water Everywhere

• The global abundance of water is very unevenly
  distributed, often available at the wrong time,
  or in the wrong place, or with the wrong quality.
• Water can be as much a hazard to health and
  property as it is a useful resource floods and
  droughts are major catastrophes.

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Extremes Are Common
Floods cause economic, social and environmental
disasters
Droughts wreak havoc on farmers and cause urban
shortages.
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Key H20 Characteristics

• Water is the prime constituent of all living
  organisms.
• Water moves easily - from one physical state to
  another, and from one place to another.
• Water is a superior solvent.

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Importance of Water Properties
Chemical spills, excess nutrients acids
dissolved in H20 can lead to massive die offs.
Lack of access to clean water supplies can
quickly lead to dehydration and death.
Running water can quickly erode topsoil rendering
farmland infertile and streams contaminated.
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Managing Water

• Water resource development is characterized by
  lumpy investments.
• Long term planning horizons and massive periodic
  funding sources are required.
• Water is highly interdependent with other
  resource management issues, and a range of
  geographical and environmental factors.

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A Lumpy Investment
The 450 million Los Vaqueros Project, completed
at the end of 1997, was the largest capital
project in Contra Costa Water District's 63-year
history. It may yet be expanded 10 fold as part
of the Bay Delta process to serve Southern CA
storage needs.
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SupplySide Management

• Water management in the United States and
  elsewhere has traditionally focused on the
  "supply-side management" approach.
• Water has been developed for users wherever and
  whenever they have needed it and been a catalyst
  for settlement and growth.
• Increasing costs and environmental problems
  require a new approach be adopted.
• This will involve better environmental management
  and water conservation and an emphasis on
  demand-side solutions.

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The Supply Side
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The Demand Side
Use drip irrigation instead of sprinklers or
flooding.
Install drought tolerant landscaping called
xeriscape, not English gardens.
Junk those old guzzling 7gpf toilets for the
1.6gpf ULFTs
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The Changing Situation

• Urban populations are expanding at a tremendous
  rate, placing growing demands on overburdened
  water supply systems.
• The lowest cost and most reliable sources of
  water for large cities have already been
  developed.
• Worldwide, the average cost of most new water
  projects is expected to be two to three times
  that of existing investments.

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Water as a Right

• The UN declared that "all peoples, whatever their
  stage of development and their social and
  economic conditions, have the right to have
  access to drinking water in quantities and of a
  quality equal to their basic needs".
• There are currently around 240 million urban
  dwellers and 840 million rural dwellers in the
  world without access to safe drinking water -a
  total of 1.1 billion people.

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Water as an Aesthetic
The image in this picture is skewed - not just by
the photographer- but for what it
represents. How many of us drink bottled water?
Why? And at what cost?
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How Lucky We Are

• In developing countries, fully 80 of diseases
  and over 33 of deaths are related to the
  consumption of contaminated water.
• It is said that an average of 10 of each persons
  productive time is sacrificed to the debilitating
  impacts of water-related illness.
• In countries like Zaire, only 30-40 of the urban
  population may have safe drinking water and only
  20-30 sanitation.

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How the Other Half Lives
Even simple pit latrines are missing from
millions of homes in the less developed world.
Water-borne diseases like guinea worm
(dracunculiasis) could be avoided with simple
filtering.
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Water Resources Management

• The application of structural and nonstructural
  measures to control natural and built water
  resources systems.
• Measures - the range of tools and techniques used
  by water managers technologies, laws and
  regulations, pricing, public education, etc.
• Control - all actions that result in water
  storage, allocation, conveyance, use, treatment,
  etc.
• Systems - a combination of water control
  facilities and environmental elements working
  together to achieve water management goals.

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Water Resources Systems

• Water control facilities - built infrastructure
  for managing water quality and quantity for
  supply, drainage, flood control, navigation, etc.
• Environmental elements - the natural components
  of the hydrological cycle - the atmosphere,
  watersheds, stream channels, aquifers and
  groundwater systems, lakes, estuaries, seas,
  oceans, etc.

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Control Facilities
The sinuous California Aqueduct wheeling water
down south.
Dams like the Glen Canyon and Lake Powell
Reverse osmosis systems for desalination
Water treatment plants taking out harmful
impurities.
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Environmental Elements
The atmosphere is a key element in our water
systems
Snowpack provides summer runoff
Rivers collect and transport surface water.
Aquifers are fed by infiltrating surface water
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Water Sources

• Water sources are the physical stores and flows
  of water on the earth (water bodies).
• Natural stores include rivers, streams, lakes,
  aquifers (and snow packs).
• Natural stores are augmented by dams and
  reservoirs, artificial recharge systems, and
  other human modifications.
• Water flows naturally between stores and is moved
  from source to source by conveyance systems such
  as aqueducts and canals.

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Water Source Considerations

• The best water sources are cheap to access,
  predictable in yield, of the highest natural
  water quality, and of least risk from
  environmental changes.
• Which water resource a community exploits is a
  function of many factors including history,
  economics, geography, leadership, environmental
  context, among others.
• Many water users rely on multiple sources of
  water to meet their needs.

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The Hydrological Cycle

• The hydrological cycle takes place within the
  hydrological unit called the watershed.
• The watershed is basically the area of land from
  which water drains to a particular water body.
• The geological, geomorphological, vegetative, and
  human character of the watershed determines the
  pathways that water takes following its input as
  precipitation.

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The Watershed
The form of this high mountain watershed can be
seen, draining the steep bowl like headwaters
into the steeply cut steam canyon.
The topographic contours clearly delineate this
urban watershed from its adjacent neighbors.
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The H2O Cycle and its Pathways
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Exploiting the H2O Cycle

• Humans modify the hydrological cycle by slowing
  down, speeding up or bypassing important elements
  of it to meet our own needs.
• The ways we modify the hydrological cycle are a
  major element of water resources management.

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The Watershed

• Streams and rivers converge down through the
  watershed towards a common base level.
• Water that falls in the headwater reaches will
  eventually move downward above or below ground
  until it reaches this base level.

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Managing Watersheds

• Any characteristics the water has or attains
  within the headwaters or middle reaches of the
  watershed will be transmitted to the lower
  reaches of the watershed.
• To manage the quantity and quality of a water
  resource, we must thus manage the conditions
  within the whole watershed.

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Balancing Interests

• Communities upstream have little interest in what
  happens to water as it moves downstream in a
  watershed
• Downstream water users are critically dependent
  upon the actions of those living and working
  upstream.
• Water resources management frequently seeks to
  balance/protect these interests.

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Do You Know?

• Where does your water come from?
• What are the environmental characteristics of
  your source area?
• What is done to your water by those who
  distribute it to you?
• What are you actually paying for and how much do
  you pay?
• Where does it go when you are finished with it?
• How reliable is your supply now and in the future?

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Know Thy Source

• To exploit a water source efficiently we need to
  understand it.
• This requires hydrological measurement and
  monitoring to quantify volumes, rates/yields,
  quality, and variations.
• Important tools in water resources management are
  the water balance of a watershed and the
  hydrological model.

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The Basic Water Balance

• The law of continuity InputOutput
  ? ?Storage
• PQE??SMS??GWS??DS?GWO
• P total precipitation input
• Q total streamflow
• E total evapotranspiration loss
• ?SMS change in soil moisture storage
• ?GWS change in groundwater storage
• ?DS change in depression and snowpack (surface)
  storage
• GWO groundwater outflow at depth