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Water Use

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... pipes, leaking valves, leaking faucets, bleeding toilet tanks. ... the Sacramento-San Joaquin River Delta and SF Bay ecosystems for fish and wildlife. ... – PowerPoint PPT presentation

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Title: Water Use


1
Water Use
Source PBS Television (http//www.kteh.org/cadill
acdesert/episode4d.html)
2
Water Use
  • Water should always be allocated to the highest
    and best beneficial use.
  • There are always allocation choices, and what is
    the most beneficial use for a given unit of water
    is a subjective issue.

3
Water Use
  • What do we mean by use? It depends on the
    semantic context.
  • Writers commonly interchange use, demand and
    consumption, sometimes confusingly.
  • Use as in demand the volume of water withdrawn
    from a water delivery system or directly from a
    natural source by a particular entity in a
    particular unit of time.

4
Consumption
  • Consumption in the personal sense - as in volume
    of drinking water (e.g. 2 l per day).
  • Consumption in the household (etc.) sense - as in
    volume of water recorded daily on a household
    meter(e.g. 1600 l per day).
  • Consumption in the hydrological sense - as in
    volume withdrawn from a water body that is not
    returned to that body.

5
Consumptive uses and withdrawals
  • Hydrologists talk of consumptive and
    non-consumptive uses of water.
  • Hydrologists also talk of withdrawals and
    in-stream uses.
  • Consumptive uses require withdrawals, but not all
    withdrawals are consumptive.
  • In-stream uses are non-consumptive and require
    the water to be used in-situ within the water
    body.
  • A special class of in-stream uses are often
    termed environmental water demand.

6
In-stream uses
  • In-stream uses are those that utilize water
    in-situ as it resides in or moves through the
    water body itself.
  • Examples include navigation, wildlife protection,
    scenic values, recreation (e.g. rafting), waste
    dilution and assimilation.
  • In many water bodies, minimum in-stream
    requirements are specified which may have highest
    (inalienable) priority within the water rights
    system.

7
Waste disposal
  • Waste disposal is a significant and common use to
    which rivers, streams and aquifers are put.
  • How much waste can be safely handled depends on
    many factors including water body ambient quality
    and capacity to dilute/neutralize, as well as on
    waste volume and concentration.

8
Non-consumptive withdrawals
  • Some water uses merely borrow the water for its
    mechanical or thermal properties and release it
    back to the body close to the point of
    abstraction.
  • Hydropower is the classic example of a
    non-consumptive withdrawal.
  • Many cooling systems return only part of the
    water withdrawn due to evaporative losses.

9
Temporary withdrawals
  • Although not consumed, temporary withdrawal may
    physically or chemically alter the water in the
    process (temperature, contamination).
  • The rerouting of water may create major
    environmental changes.
  • The returning water may have different properties
    as a result of its withdrawal.

10
Hydropower withdrawals
  • Example Hydropower generation
  • Water is usually dammed then rerouted through a
    tunnel and turbine.
  • Damming changes water quality (temperature,
    oxygen, sediment load).
  • The dam is a physical barrier to fish,
    navigation, etc.

11
Consumptive withdrawals
  • Water is withdrawn for uses which ultimately
    result in its evaporation and return to the
    beginning of the water cycle as atmospheric vapor
    (classic example is irrigation water).
  • Water is withdrawn and transferred to a different
    water body via a variety of mechanisms (e.g. in a
    bottle, in a product, via a pipeline, through
    seepage, etc.).
  • Not all consumptive withdrawals are actually
    evaporated and are partially returned to the
    originating body somewhere in the system.

12
Complicating Factors
  • Transferred water that is not evaporated must be
    added to the water balance of the water body into
    whos system it is released.
  • Many withdrawals are intra-watershed with respect
    to a given water body and any unevaporated water
    released back into the system must be accounted
    for (these are called return flows).
  • Classic return flows include irrigation water
    seepage losses and runoff and sewage effluent
    discharge.

13
Understanding water use
  • Disaggregated data is very useful to water
    planners.
  • Effective demand forecasting, drought management
    and water conservation planning require
    comprehensive information on how customers
    actually use their water.
  • Such information is also a key element of billing
    wastewater treatment fees.

14
Accounting for water use
  • Measuring demand requires using pipeline meters,
    flow sensors or pumping data.
  • In urban areas, water meters allow providers to
    bill users based on volume.
  • Assigning codes to accounts allow providers to
    aggregate demand by type of user.
  • Further disaggregation of demand by type of use
    requires more detailed information that requires
    some form of audit study.

15
Urban demand for water
  • Depends on the character and relative number of
    customers in different classes, and their water
    use habits.
  • Urban customer classes are usually industrial,
    commercial, governmental, residential (single
    family, multi-family), landscape.
  • A key concern in many urban areas is the
    proportion of demand uselessly lost during
    delivery as opposed to used productively.

16
Unaccounted for Water
  • Distribution system losses evaporation, seepage,
    leakage from mains upstream of customer meters
    (ruptures, breaks), leaks from valves, hydrants
    and meters, leakage and overflow from tanks and
    reservoirs, backwash, etc. from treatment plants.
  • Metering and other losses source meter errors,
    supply meter errors, unauthorized consumption
    (illegal connections, illegal bypasses),
    meter-reading errors (temporary,
    self-correcting), unmetered flushing and
    fire-fighting use.

17
Accounted for losses
  • Customer losses (note that these will be billed
    as legitimate uses where meters are installed)
    broken pipes, leaking valves, leaking faucets,
    bleeding toilet tanks.
  • Customer inefficiencies (note that these will be
    billed as legitimate uses where meters are
    installed) unnecessary or inefficient water use
    practices (e.g. irrigating in a rainstorm).

18
Residential water uses
  • Generally landscaping (33), interior use (66).
  • Interior uses - toilets (36), bathing (28),
    laundry (20), misc. faucet use (13),
    dishwashing (3).
  • California average is around 120 gallons per
    capita per day (gcd), 80 gcd inside, 40 gcd
    outside.

19
Industrial and commercial
  • Indoor process (industry-dependent), HVAC
    (boiler make-up, evaporative cooling),
    sanitation, worker hygiene, janitorial, fire
    control, catering.
  • Outdoor irrigation, dust-suppression,
    hosing-down, fire control.
  • Industrial demand is highly skewed and
    frequently, 90 of the total use will be
    accounted for by around 10 of the users within a
    given distribution system.

20
Agricultural and Public Sector
  • Agricultural Irrigation, processing (sluicing,
    grading, washing, etc.), hosing-down, livestock
    watering, worker and animal hygiene, pesticide
    applications, etc.
  • Public Industrial and commercial-type uses (as
    appropriate), irrigation (parks, dividers, etc.),
    water main and sewer main flushing,
    fire-fighting, swimming pools, water feature
    make-up, etc.

21
Agricultural demand for water
  • The demand for agriculture is principally a
    function of area of land cultivated, crop types,
    type of farming system, irrigation technology,
    irrigation efficiency, climate and soil type.
  • In CA, around 9 of irrigated agriculture is by
    drip, 24 sprinkler and 77 furrow or flooding.

22
Environmental water demand
  • Wild and scenic river requirements
  • Fishery and wildlife preservation
    (freshwater-saline water balances, temperature
    regimes, turbidity levels, flooding patterns, and
    current velocities and directions)
  • Recreational needs.

23
Demand variations
  • Demand can vary by time of day, day of the week,
    season, and over a period of years in response to
    trends in water use, population, etc.
  • Agricultural demand is highest during the day in
    the summer growing period.
  • Urban demand is highest during the day on summer
    weekdays.

24
Demand variations
  • Environmental water demand is generally very site
    specific.
  • For example, in California it is highest during
    the Fall, coinciding with the Chinook Salmon run.
  • It depends on when the critical conditions occur
    for endangered species life-cycles and habitat
    preservation.

25
Conflicts over water
  • In-stream v Consumptive withdrawals e.g. over
    Sacramento/San Joaquin salmon v irrigated farm
    production.
  • Consumptive upstream v. consumptive downstream
    e.g. Guadalupe River, TX., Jordan River, Tigris
    Euphrates.
  • Instream v Non-consumptive withdrawals e.g. CA
    hydroelectric dams v migrating fish.

26
More irrigation
  • Currently, irrigated agriculture produces around
    40 of the worlds food supply and uses about 70
    of water supplies.
  • World food production will only keep pace with
    population growth if more irrigation occurs, thus
    requiring more water to be allocated to
    agriculture.

27
Growing cities
  • By 2025, the number of world cities with over 1 m
    people will double to over 600.
  • The vastly increased demand for high quality
    water for domestic, commercial and industrial use
    will cause even greater allocation conflicts
    between farmers and the cities and
    environmentalists.

28
Water ownership
  • Water laws and regulations have grown out of
    complex water use situations such as the conflict
    over water during gold rush times in the Sierra
    Nevada.

29
Who owns water?
  • Water in nature is generally usufructuary -
    individuals only have the right to use it, not to
    own it.
  • In most cases, water is owned by the nation or
    the state, which recognizes or assigns an
    individuals rights to beneficially use the
    water.

30
Riparian rights
  • These are the rights to use water as a result of
    the ownership of property that abuts a natural
    water body.
  • The riparian water right is said to be part and
    parcel of the land, unless expressly and legally
    excluded from the land title.

31
Riparian rights considerations
  • All riparian rights are considered equal.
  • Riparian rights are often unadjudicated (they are
    not quantified).
  • Riparian rights are usually superior to all other
    water rights.
  • Sub-division of riparian lands or acquisition of
    adjacent non-riparian lands creates tricky legal
    issues.

32
Riparian rights example
  • Which lands are riparian lands?
  • ____________
  • Which lands are non-riparian lands?
  • ____________
  • Could Farmer B take more water if she acquired
    land D?

A
River Blue
C
E
B
G
D
F
33
Appropriative rights
  • These are the rights to divert and use a specific
    quantity of water for reasonable beneficial use
    in a specific non-riparian location.
  • They are governed by the first-in-time,
    first-in-right doctrine.
  • Most appropriative rights systems use the use-it
    or lose-it principle.

34
Appropriative rights adjudication
  • In theory, in times of scarcity, senior rights
    holders get priority for available water
    supplies.
  • In practice, courts have used the public trust
    doctrine to give junior rights holders an equal
    share during drought years.

35
Appropriative rights history (Ca)
  • The CA. Supreme Court codified the appropriative
    rights doctrine in 1855 in the case of Irwin v
    Phillips, protecting the sources of water of the
    early miners from Johnny-come-latelies.
  • All appropriative rights granted after 1914
    received a permit listing the location of the
    diversion, the place of use and the quantity to
    be diverted.

36
Correlative rights
  • These are the groundwater equivalent to riparian
    rights.
  • If there is water below your land, it is yours to
    use.
  • If the groundwater basin is adjudicated, you will
    be limited to a specific share of the aquifers
    sustainable yield. If not, you can take all you
    want.
  • Lack of adjudication can lead to many conflicts.

37
California water rights
  • Article X, Section 2 of the California
    Constitution applies to all water rights,
    prohibits waste of water, and requires
    reasonableness of use.
  • The State Water Resources Control Board grants
    permits, and adjudicates water rights and water
    rights disputes.
  • Water rights disputes are common and complex
    (Twain - whiskey is for drinkin, water is for
    fightin)

38
Water regulations
  • In most countries, there is usually a complex set
    of federal, regional (state) and local
    regulations concerning water.
  • Different legislative branches that have
    responsibility for different sectors - the
    environment, public health, forestry, transport,
    mining, etc. - set policy and draft laws that
    affect water resources.

39
US regulations - CWA
  • Clean Water Act of 1977. Developed out of the
    Federal Water Pollution Control Act of 1972, it
    prevents pollution of surface water sources from
    point pollutants and, more recently, from
    non-point pollutants found in stormwater.

40
US regulations - SDWA, WSRA
  • Safe Drinking Water Act of 1974 prevents the
    supply of contaminated drinking water to the
    American Public.
  • Wild Scenic Rivers Act of 1968 maintains the
    natural beauty, biology and wildness of American
    rivers threatened by the construction of dams,
    diversions, canalization, etc.

41
US regulations - ESA
  • Endangered Species Act of 1973 prevents the
    extinction of mostly native animals and plants
    through the destruction of important habitat,
    particularly aquatic habitat (hence has key role
    in water resource management).

42
US regulations- NEPA
  • National Environmental Policy Act of 1970
    mandates requirements for efficient resource use
    that avoids general degradation, risk to health
    and safety, or other negative consequences of
    development, and requires the performance of
    Environmental Impact Statements (CA equivalent is
    CEQA).

43
Regulations at the State level
  • In many cases, laws enacted at the federal level
    are delegated to the States whos own
    authorities, such as the CA State Water Resources
    Control Board, are responsible for
    implementation, e.g. the Clean Water Act in CA is
    enforced through the CA Porter-Cologne Water
    Quality Control Act of 1969.

44
California water regulations
  • In CA, water use and supply are controlled under
    a complex system of intermeshing federal and
    state laws, common case laws, federal and state
    statutes, constitutional amendments, court
    rulings and contract agreements that in some way
    govern and regulate how water is developed,
    allocated or used.

45
CA sources of information
  • CA has perhaps more water legislation on the
    books than any other State.
  • A complete summary of water laws can be seen in
    Volume 1, Chapter 2 of the CA Water Plan (160-94)
    with more recent updates tackled in Volume 1,
    Chapter 2 of the (160-98) Plan.
  • Information can also be obtained on the web at
    various sites such as http//ceres.ca.gov/topic/e
    nv_law/water/
  • An excellent book on the subject is California
    Water by Littleworth and Garner, 1995.

46
Important federal agencies
  • The primary federal agencies for water resources
    development and protection include Environmental
    Protection Agency, US Army Corps of Engineers, US
    Bureau of Reclamation, US Geological Survey, US
    Department of Agriculture and the US Fish and
    Wildlife Service.

47
Important CA agencies
  • Important CA State agencies for setting or
    enforcing water-related regulations include the
    CA State Legislature, CA Supreme Court, State
    Water Resources Control Board, CA Resources
    Agency (esp. CA Dept. of Fish and Game CA Dept.
    of Water Resources), and the CA Dept. of Health
    Services,

48
Important CA govt. agencies
  • An interesting and important new player in CA is
    the CAL-FED Program.
  • A state-federal partnership, its role is to
    develop a comprehensive solution to provide more
    reliable water supplies while stabilizing the
    Sacramento-San Joaquin River Delta and SF Bay
    ecosystems for fish and wildlife.
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