Water Issues

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Water Issues

• Where is the Water?
• Hydrologic Cycle
• Water Under Foot (Soil Water, Ground Water,
  Aquifers, Water Tables, Wells)
• Water Quality
• Dams and River Regulation
• California Water Distribution

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Hydrologic Cycle

• Evapotranspiration
• Surface Water streams, lakes
• Soil Water used by plants
• Ground water depends on soil porosity
• Springs and wells artesian and subartesian

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Water Under Foot
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• POLLUTANTS IN WATER toxins (cause damage to
  human body, often kidneys or liver, or cause
  disease or cancer)
• Natural selenium, arsenic (Bangladesh), others
• Anthropogenic (human-caused)
• Point Source
• Industry heavy metals (mercury, cadmium,
  thalium, others), polychlorinated biphenyls
  (PCBs), mercury - from coal burning harms infants
  and pregnant women, others
• Agriculture animal waste encourages toxic
  bacteria growth, fertilizer causes excess
  nitrogen/eutrophication, dioxins (from
  herbicides), hormones, antibiotics
• Sewage leaks, overflows

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Water Quality

• Non-point source
• Urban Storm Run-Off Oil Changes, Anti-Freeze,
  Detergents, Lawn Fertilizers become lodged in
  river and marsh sediments, endangering wildlife
  and plants.

Eutrophication
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Ocean Dead Zones

• Click Map for MSNBC Video

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Dams and Global River Degradation
Shasta Dam, CA
AswanDam, Egypt Lake Nasser
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The Geography of Large Dams

• Over 39,000 large dams by 1986

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The Impact of Dams

• Northern third of the world 77 overall impacted
  by dams and river regulation. (Dynesius and
  Nilsson, 1994)
• Industrialized counties - more impact
• USA 98 (Escheverria et. al., 1989)

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Upstream Impact of Dams

• Environment
• Loss of terrestrial/riparian habitat and species
• Creation of artificial lacustrine (lakes) system
• exotic species introductions
• Reservoir/storage for contaminants

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Upstream Impact of Dams

• Cultural / social
• Loss of cultural resources
• Displacement of families
  (villages, regions)
• Water quality hazard
• Economic
• Shift in land use / economy
• Water loss via evaporation
• Water loss via seepage
• Aesthetic
• landscape inundated

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Upstream Impact of Dams

• Built 1956-1966.
• Aesthetics Glen Canyon, Colorado River

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DownstreamImpacts of Dams

• Altered hydrology - no seasonality
• Altered water quality/character
• Modify nutrient cycling
• Reduce sediment supply
• Channel adjustments
• Habitat modification
• Species impacts
• River fragmentation

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The Dam Balance

• Some dam removal (small dams) or operational
  changes (larger dams)
• Bruce Babbit (Secretary of the Interior) oversaw
  the creative destruction of two California dams
  in 2000 (Saelzer Dam on Clear Creek near Redding,
  for Salmon, and Matilija Dam in SoCal).
• Dams continue to be built until good sites are
  gone, or it is not economic to build them.
• Global numbers? We do not know.

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Three Gorges Dam

• World's largest hydroelectric dam, Three Gorges,
  on Yangtze River.
• 1.2 - 1.9 million will be displaced.
• Power creation roughly equal to 18 nuclear
  plants.
• The entire project is to be completed in 2009.

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Californias Water System

• Californias Water Projects
• Los Angeles Aqueduct
• Salton Sea
• Colorado Aqueduct
• Mono Lake Decisions

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California Hydrography
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Native Water Issues
Distribution of surface water 70 is in 20 of
state, mostly in north. Population is mainly in
south and central. Sacramento River System 1/4
of total flow - 1/3 of this water is from the
northwestern tributaries. Only 1/10 from San
Joaquin. Seasonal Variation Dry summer water
arrives when farmers least need it. Irrigation
and storage are necessities. Winter flooding In
1840s the only way to get to Sacramento from the
west was by skiff, not horse. Seasonal floods and
native streams provide habitat for spawning fish,
including steelhead trout and salmon. Threatened
by damns and water control.
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California Aqueducts
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California Dams and Reservoirs
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Los Angeles Aqueduct (DWP)Eastern Sierra

• Started in 1908 by William Mulholland
• appropriated water feeding Owens Valley
• taps surface flow from Eastern Sierra south
• 250 miles, cost 25,000,000 and took five years
• pipe and flume, tunnel, and trench
• gravity feed, no pumping
• generates hydroelectric power
• L.A. purchased riparian land, used appropriation
  rights to get away with this. Ranchers in Owens
  Valley fought back with dynamite and guns -
  Californias only range war.

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Mono Lake

• In 1941, L.A. DWP started diverting Mono Basin
  streams to add to L.A. Aqueduct.
• Mono Lakes volume halved while salinity doubled.
  The simple ecosystem began to fail and threatened
  migrating birds and nesting gulls.
• The state and courts now mandate raising the
  level of the lake 17 feet. It will take about 20
  years.

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The Salton Sea

• Man-made by accident in 1905.
• Irrigation in Imperial Valley had flooded an
  ancient overflow channel of the Colorado River.
• Unusually heavy spring runoff and lack of control
  gates caused a two-year flood into the Salton
  Sink.
• The Southern Pacific Railroad had to move its
  tracks five times that season to higher ground.
• Eventually the S.P.R.R. took control and put the
  river back but by then the Salton Sea was
  created.
• Hoover Dam now controls Colorado and prevents
  delivery of sediment to Yuma and the delta.

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