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• Follow the test kit manufacturers’ directions specifically. Do not alter
the procedure to suit your needs or take shortcuts; this risks skewed re-
sults.
• Do not intermix different manufacturers’ reagents, particularity colori-
metric ones, unless they are the exact same concentration.
RESEARCH WORK
24. Choose one of the water quality parameters described in the text be-
low; choose a water source. Test a sample from the source for the chosen
parameter. If the test is not available find data about it.
Write a short report.
COMMON WATER QUALITY TERMS/PARAMETERS
Aesthetic Objective (AO) – levels of substances or characteristics of
water that can affect its acceptance by consumers or interfere with practices
for supplying good quality water.
Alkalinity – is not a specific substance but rather a combined effect of
several substances. It is a measure of the resistance of water to a change in
pH. The alkalinity of most prairie waters is in the range of 100 to 500 mg/L,
which is considered acceptable. Water with higher levels is often used. Alka-
linity is a factor in corrosion or scale deposition and may affect some live-
stock when over 1,000 mg/L.
Calcium and Magnesium – cause "hardness" in water. They are not
hazardous to health but are undesirable because they may be detrimental for
domestic uses such as washing, bathing and laundering. It also tends to cause
encrustations in kettles, coffee makers and water heaters.
Coliforms (Fecal) or (E. Coli) or (Escherichia coli) - E. coli is a mem-
ber of the total coliform group of bacteria and is the only member that is
found exclusively in the faeces of humans and other animals. Its presence in
water indicates not only recent faecal contamination of the water but also the
possible presence of intestinal disease-causing bacteria, viruses, and proto-
zoa.
Coliforms (Total) – The presence of these bacteria may indicate con-
tamination in a water supply. This group of bacteria is found in feces, soil,
and vegetation and is used as an indicator of the bacteriological quality of
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