Download Stream Assessment

Unit 1 - Assessment of a Stream
I. Importance of Water
Water Properties
 Polarity (adhesion, cohesion, capillary action, surface tension, group nonpolar
substances)
 Universal Solvent
 Expands when Freezes
 High Specific Heat
Water Statistics
 The earth is made up of 65-75 % of water
 97.2% of that water is saltwater
 2.2% is locked up as ice
 0.6% is ground water
 .001% is lakes
 .0001% is rivers
 Bottom Line- fresh water is a valuable and limited resource
 Not only the quantity of water is important, but the quality as well.
 Of that small amount of freshwater we do have a lot of it is of poor quality
 We will be measuring the water quality streams from Jackson Pass to Rexburg (Teton
Watershed)
II. Water Pathways
A. Surface Water
 Hydrological Cycle
 Watersheds
 Rain and snow falls and runs
downstream from mountain
springs- creeks - small river - large
rivers –ocean (hydrological cycle)
Teton-Snake-Columbia Watershed
B. Ground Water
 Most of the available freshwater is in the form of groundwater ¾ of this ground water does
takes centuries to recharge
 There is a relationship between ground water and surface water
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Snake River Aquifer
III. Parts of a Stream
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Run
Riffle (riff)
Bed
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Pool
Flood Plain
Wetted
perimeter
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Headwater
IV. Monitoring Water Quality
Biological - Macro-invertebrates (indicator species)-presences indicates health of stream
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Plecoptera (stonefly)
Trichoptera (Caddisfly)
Ephemeroptera (mayfly)
Plecoptera
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Stonefly nymph
Six legs
Unusually two tailed
Swims in side to side
Very sensitive and will only be found in high quality water
Good indicator species
Trichoptera
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Caddiesflies
Caterpillar-like body; abdomen usually enclosed in a case made of stones, leaves, twigs, or
other natural materials.
Head capsule well-developed with chewing mouthparts
Thread-like abdominal gills usually present in case-makers
One pair of hooked prolegs often present at tip of abdomen
Ephemoptera
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Mayfly
Six legs
Usually three tailed
Up and down swimming motion
Others
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Anything besides these three category we record as others and high number of others will
indicate an unhealthy stream.
Chemicals
Temperature
Nitrates
Turbidity
Hardness
Dissolved
Oxygen
Phosphates
Total Dissolved
Solid
Alkalinity
Sulfates
pH
Turbidity - This is a general measurement of how cloudy the water is.
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This measurement is
important to look at the
following:
o Erosion
o Stable or Not
o Algae blooms
o Other problems
Turbidity in water is
caused by suspended
matter such as clay, silt,
and organic matter and by
plankton and other
microscopic organisms
that interfere with the passage of light through the water
Turbidity itself is not a major health concern, but high turbidity can interfere with disinfection
and provide a medium for microbial growth.
Factors that Influence Turbidity
o High Flow Rates
o Decaying Plants and Animals
o Soil Erosion
o Bottom-Feeding Fish
o Urban Runoff
o Algal Blooms
o Wastewater and Septic System
o Flooding
Effluent
It is measured using a turbimeter and will record in NTU (nephalometric turbidity units).
Testing Methods
Titration
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Measures unknown amount of a chemical by reacting it with a known amount of
another chemical
Dissolved Oxygen, Alkalinity, and Hardness are measured using this technique
Dissolved Oxygen
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Oxygen enters the water by absorption directly from the atmosphere or by aquatic plant
and algae photosynthesis. Oxygen is removed from the water by respiration and
decomposition of organic matter.
Factors influencing DO
o Volume and velocity of water flowing in the water body
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Climate/Season
The type and number of organisms in the water body
Dissolved or suspended solids
Amount of nutrients in the water
Alkalinity
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Alkalinity is a measure of the buffering capacity of water, or the capacity of bases to
neutralize acids. Alkalinity does not refer to pH, but instead refers to the ability of water to
resist change in pH. The presence of buffering materials help neutralize acids as they are
added to the water.
Factors:
o Geology and Soils
o Changes in pH
o Sewage Outflow
o Hardness
Hardness - is measure of polyvalent cat ions (ions with a charge greater than +1) in water. Hardness
generally represents the concentration of calcium (Ca2+) and magnesium (Mg2+) ions. Other ions,
such as iron (Fe2+) and manganese (Mn2+), may also contribute to the hardness of water, but are
generally present in much lower concentrations. Waters with high hardness values are referred to as
"hard," while those with low hardness values are "soft".
Factors Affecting Hardness
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Geology
Mining
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Industrial Discharge
Sewage Outflow
Spectrophotometer (DR2400)
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Measures concentration of an element by measuring amounts of light absorbed or
transmitted through sample
Wavelength of light determines type of chemical in solution
Amount of light absorbed or transmitted determines concentration of chemical in
solution
Nitrate, Phosphate, and Sulfate will be measured with the DR2400
Nitrate
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Inorganic forms include nitrate (NO3), nitrite (NO2), ammonia (NH3), and nitrogen gas (N2).
Organic nitrogen is found in the cells of all living things and is a component of proteins,
peptides, and amino acids. Nitrogen is most abundant in Earth’s environment as N2 gas,
which makes up about 78 percent of the air we breathe.
methemoglobinemia or "blue baby" syndrome (because the nose and tips of ears can
appear blue from lack of oxygen
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"brown blood disease" in fish
Factors for Nitrate
o Wastewater and Septic
System Effluent
o Fertilizer Runoff
o Animal Waste
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Fossil Fuels
Industrial Discharge
Eutrophication
Phosphorus
Phosphorus - is a natural element found in rocks, soils and organic material. Phosphorus clings
tightly to soil particles and is used by plants, so its concentrations in clean waters is generally very
low.
Factors:
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Wastewater and Septic System
Detergents
Fertilizers
Animal Waste
Development/Paved Surfaces
Temperature
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Measures average kinetic energy of a substance
Measured in Celsius, Fahrenheit, or Kalvin
Measured using a thermometer
pH
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Measure of acid or base
Acid - dissolved hydrogen H+ ions in solution
Base - dissolved hydroxide OH- ions in solution
Measured with pH meter
pH scale
o Below 7 = acid (lower = more acidic)
o Above 7 = base (higher = more basic)
o 7 = neutral
Factors Affecting pH:
o The concentration of carbon dioxide in the water
o Geology and Soils of the watershed
o Drainage from Mine Sites
o Air Pollution
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Industrial Discharge
Phosphate Mining
Forest Fires
Synthetic Materials
TDS
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This is a general measurement of the concentration of all dissolved metals within a sample
Use a TDS meter to calculate
Factors:
o High Flow Rates
o Wastewater and Septic System
o Soil Erosion
Effluent
o Urban Runoff
o Decaying Plants and Animals
o Bottom-Feeding Fish
V. Expected Range for Teton Watershed
 Turbidity: less than 5 NTU
 Nitrate: 0.5-4.5 mg/L
 Phosphate: less than 1 mg/L
 Sulfate: 1-18 mg/L
 pH: 8-9
Physical Assessment
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DO: 9-13 mg/L
Hardness: 90-175 mg/L
Alkalinity: 75-155 mg/L
TDS: 90-160 mg/L
Shape, volume, substrate, and vegetation
Scientific Process-Record and Analysis of Tests
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Computer
o Excel-Ms. Ross will teach you
 make sure all numbers are entered correctly
 Use graph to analyze
 Use statistical test to analyze
 Computer is only as useful as the person entering the data
What does all this mean??
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A healthy stream needs to have a chemical balance to support its ecosystem and the need of us humans
Because fresh water is such a limited resource it is important to monitor its quality and support measures to
keep the streams healthier for all