testing for water quality. ph why test? changes in ph indicate the presence of contaminants...
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Testing for Water Quality
pH
• Why Test? Changes in pH indicate
the presence of contaminants
• Comments Healthy aquatic
organisms prefer a pH range of 6.0-8.0
Less than 7 = Acidic 7 = Neutral Greater than 7 = Basic
Dissolved Oxygen (DO)
• Why Test? Low DO levels
indicate wastes in the water; unhealthy
• Comments High DO indicates
healthy, well-aerated water
Less than 3 ppm = bad for fish
5-6 ppm needed for growth of fish
Coliform Bacteria
• Why Test? If present, disease-
causing organisms are probably there as well.
• Comments This is a key first
test for water safety.
Not purple = presence of bacteria, bad
Nitrates
• Why test? High nitrates are
harmful to humans; can cause eutrophication
• Comments Nitrates come from
fertilizer, wastewater, and runoff (agricultural).
Less than 4 ppm = good
Greater than 40 ppm = unsafe to drink
Phosphates
• Why test? High phosphate
levels cause eutrophication
• Comments Phosphates come
from agricultural and lawn runoff and detergents.
Greater than 0.03 ppm will encourage algae growth
Total Alkalinity
• Why Test? Measures water’s
ability to neutralize acids
• Comments Loss of buffering
capacity can affect pH
100-200 ppm will stabilize pH
Total Hardness
• Why Test? Excess amounts of
Calcium and Magnesium
• Comments Affects plant and
animal growth rates, hard water can leave deposits and decrease soap suds
Levels 60-120 ppm is medium range
Ammonia
• Why Test? Comes from
bacterial decomposition
• Comments Can be toxic to fish
and is found in areas with a lot of decaying materials
Levels 5-10 ppm are too high
Chloride
• Why Test? Major component of
water and sewage, gives a salty taste
• Comments Salt can affect
plants and animal life
Drinking water should be less than 250 ppm
Chromium
• Why Test? A toxic chemical
from industrial waste
• Comments Can cause cancer in
drinking water Over 0.5 ppm is
untreated waste water
Free & Total Chlorine
• Why Test? Only present in
chlorinated water (sterilized and
disinfected water)
• Comments Swimming pools = 1 to
3 ppm Drinking water = 0.5
ppm Too high is fatal to
plants and fish
Iron (II)
• Why Test? Small amounts is
natural Acid mine drainage
can increase levels
• Comments Greater than 0.2
ppm is generally unacceptable
Copper (I, II)
• Why Test? Small amounts is
natural Industry or pipes
can elevate levels
• Comments Greater than 1.0
ppm will give a bitter taste
Drinking water is usually below 0.03 ppm
Total Nitrite as Nitrogen
• Why Test? High nitrites are
harmful to humans; can cause eutrophication
• Comments Greater than 1 ppm
increased plant growth