Environmental Science ENSC 2800

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Environmental Science ENSC 2800

• Spring 2002
• Class 5
• Historical perspective the origin of some
  Bay-Delta problems.
• Invasive species
• Sediment infilling
• Water diversions/reduced flows
• Urbanization and pollution
• Agriculture and chemical runoff

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Invasive Species Origins

• Explorers and trading ships began visiting
  northern California in the 1500's in the first
  five years of the gold rush more than 4500 ships
  sailed into the Bay.
• The barnacle, Balanas improvisus, living on
  ships hulls, was first recorded in 1853.
• Organisms had to survive transport from the
  Atlantic ports by way of Cape Horn which required
  3-4 months.
• The Atlantic Oyster was farmed in the bay from
  1869 to 1930 and brought in as juveniles from the
  east coast.
• The completion of the transcontinental railroad
  in 1869 reduced the transit time coast to coast
  to about 20 days.
• 135 Striped Bass were shipped by railcar from the
  Atlantic Coast in 1879.

(Source USGS poster - see this .pdf file Click
Here)
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Technology changes brings ballast water

• Steamship travel with steel-hulled ships in the
  1920-1930's resulted in the conversion to liquid
  ballast.
• The Japanese Oyster was transplanted in 1932-39
  and again in the late 1950's along with at least
  two"hitchhiking" species.
• The Bay became home to many merchant and military
  ships arriving from all over the world during and
  after World War II.
• Exotic species arrived in 1940-50 from an
  increasing number of countries as shipping
  expanded (USGS poster).

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Accelerating introductions

• Dedicated ballast tanks, supertankers, and short
  (2 week) transoceanic transit times have resulted
  in a higher survival rate of organisms in ballast
  water.
• Exotic species can be large (Atlantic Green crab
  and Asian clam) or small (amphipods).
• Live shellfish and other organisms can be shipped
  by air from all over the world in less than a
  day.
• Seaweed used to pack the Atlantic Lobster and
  commercial bait worms harbored and released at
  least one species of snail.
• People sometimes dump aquarium animals and
  potential food resources into local waters.
• The rate of species introductions has increased
  since 1960. There were 212 confirmed and 123
  suspected exotic species by 1996 (USGS poster).

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Sediment causes and effects (SFEP 1995)

• In the late 1700s, early Spanish explorers found
  a vast tidal marshland covered in tules.
• Trappers exploited otters and seals and seagoing
  ships navigated the Sacramento and San Joaquin
  rivers transporting supplies in and tallow and
  furs out.
• Agriculture developed and reclaimed land by
  draining marshes, making levees and burning the
  tules, eliminating filters/sinks.
• In the late 1800s, hydraulic gold mining in the
  Sierra Nevada started to fill in the delta,
  altering the navigability of river channels,
  hindering shipping activities, exacerbating
  flooding and causing water quality problems.
• To maintain shipping access, channels had to be
  dredged, the material being used to build levees
  to protect farmland from flooding and fill
  wetlands to create new farms.
• Eventually, the majority of the mudflats and
  marshes were filled in more than 95 are gone
  today.

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Changing Delta Morphology

• Between 1867 and 1887, approximately 115 million
  cubic meters of sediment was deposited in the
  Suisun Bay area.
• This is equivalent to about 2.5 cm/yr (1 inch)
  accumulation over all of Suisun Bay. Almost
  two-thirds of Suisun Bay was depositional during
  this period. Most of this is debris from
  hydraulic gold mining in the Sierra Nevada, and
  is likely contaminated with mercury which was
  used to extract gold from tailings. (USGS).
• Hydraulic mining ceased in 1884, while water
  distribution and flood control projects increased
  during the 20th century. These factors decreased
  the input of sediment to the Bay, and from 1887
  to 1990 Suisun Bay was erosional (USGS) hungry
  waters.
• This sediment was thus shunted into the San
  Francisco Bay, much of it accumulating and some
  washing out under the Golden Gate.

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Hydraulic Mining Had Vast Impacts
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USGS studies show past elevation changes along
the Delta
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Recent changes show scouring and subsidence now
dominate the Delta
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Construction of Dams and Aqueducts Divert Fresh
Flows

• Changes in the quantity, timing, and quality of
  fresh water flowing into the Delta and Bay have
  occurred as a result of damming for flood
  control, hydropower and carryover storage.
• Moreover, diversion via pumps within the Delta,
  is implicated in declines of fish species both
  because of physical removal of young fish by the
  pumps as well as habitat changes resulting from
  changing flow patterns and salinity distributions
  (USGS 2002).
• Sediment transport dynamics have been changed in
  complex ways and water quality is highly
  modified, due to reduced dilution capabilities
  and reduced flushing and counter-balance to tidal
  inflow.

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Some Dam and Diversion Milestones

• 1850 Republic of California established and
  Office of Surveyor General begins water planning
  operations.
• 1860 Levee and reclamation districts
  established to prevent flooding and drain
  wetlands for farming/settlements.
• 1908 SF begins Hetch Hetchy project (completed
  1923).
• 1931 First CA State Water Plan published
  oriented toward conservation (as defined as
  putting water to use, not drainage to ocean).
• 1930s Many major federal dams begun by Army
  Corps of Engineers.
• 1933 Federal CVP Act passed and work begun on
  the system.
• 1951 CA authorizes beginning of SWP.
• 1950s Many major state dams begun to go with
  state water project.
• 1966 New Melones Dam begins construction last
  major project before environmental movement
  kicked in.

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A Plumbers Paradise
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Population Trends by County 1860-1920 (ABAG)
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Population Trends by County 1930-1980 (ABAG)
Recent Trends and Forecasts (ABAG)
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(No Transcript)
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Urbanization and the Bay

• Urbanization has increased pressures on the
  Bay-Delta but has also focused attention on its
  functions and value.
• Oil refineries, industrial facilities, city
  streets and freeways, and wastewater plants
  provide sources and pathways for pollutants to
  the Bay.
• Urban point-source pollution (untreated sewage,
  undiluted industrial waste) was routinely
  discharged to the Bay-Delta until the late 1970s
  when CWA, etc. legislation kicked in.
• Unlined landfills for municipal and industrial
  garbage ringed the bay (e.g. Berkeley Marina
  area).
• Most of these types of problems, barring
  accidents, have now been eliminated.
• Non-point source pollution through urban runoff
  continues to be a big source of water quality
  deterioration

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This USGS map shows the location of the large
point source pollution dischargers to the
Bay-Delta and potential sources of historical
toxic runoff or groundwater inflow.
http//sfbay.wr.usgs.gov/access/WP-Intro.html
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California Agricultural Acreage in Production
(DWR 1994)
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Little pesticide data exists prior to 1990,
however we know (from CA DPR) that.

• Number of different pesticide products registered
  for sale in CA
• Number of acres treated with pesticides by aerial
  spraying in CA
• In 2000, official statistics say CA used 188
  million pounds of pesticides (active
  ingredients), up from 132 million pounds in 1990
  (unofficial say 200 million).
• Note detailed data on pesticide use can be
  gotten officially from the Dept. of Pesticide
  Regulation at http//www.cdpr.ca.gov/index.htm
  and unofficially from the Pesticide Action
  Network http//www.pesticideinfo.org/Search_Use.ht
  ml or Californians for Pesticide Reform
  http//www.igc.org/cpr/

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AGRICULTURAL CHEMCIALS CREATED TOXIC IMPACTS AND
LEGACIESDDT first appeared around 1950. Maximum
use of DDT occurred around 1970. Concentrations
of DDT declined following the ban on DDT in
1972.See Historical and Recent Inputs of
Anthropogenic Organic Compounds to San Francisco
Bay Prospects for the Future. USGS 1998.
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This PAN map clearly shows how the central valley
part of the Bay-Delta watershed still experiences
the heaviest reported use of pesticides in the
State.