The Water Quality Tables contain the following column headings:

Station Description
Sampling Point
Location Code
This column displays the description of the locations (and the location code used) where the water quality samples were collected in the drinking water system.
Date This column shows the sampling collection date.
Time This column shows the time (24 hour system) at which the sample was collected.
Total Chlorine
Limit = 3.0
This column shows the chlorine residual, in milligrams per litre, for the sample collected on that particular date and time. The ‘Limit = 3.0’ refers to the Health Canada health-based Guideline Limit set for drinking water in mg/L.
Water Temp.
Limit = 15
This column shows the water temperature, in degrees Celsius, for the sample collected on that particular date and time. The ‘Limit = 15’ refers to the Health Canada Guideline aesthetic Limit set for drinking water (set as degrees Celsius).
Total Coliforms
Limit = 0/100mL
This column shows the number of total coliform bacteria found in that particular sample on that specific sampling date and time. The ‘Limit =0’ refers to the Health Canada health-based Limit and the BC Drinking Water Protection Regulation limit set for drinking water. To meet the microbiological standard, the BC Drinking Water Protection Regulation specifies that 90% or more of the samples collected within a 30-day period must have 0 total coliforms per 100 mL. Stated another way, the Guidelines for Canadian Drinking Water Quality specify that not more than 10% of the samples should show the presence of coliform organisms.
E. coli
Limit = 0/100mL
This column shows the Escherichia coli (E. coli) bacteria found in that particular sample on that specific sampling date and time. The presence of E. coli bacteria indicates recent fecal contamination and the possible presence of enteric pathogens in the water that may adversely affect human health.
TC Presence
Limit = Absent
This column gives the result of the ‘Presence-Absence’ test for total coliforms in water. Rather than enumerating total coliform bacteria, the test indicates only the ‘Presence’ or ‘Absence’ of total coliforms in the water. If no coliforms were found then the text lists ‘Absent’. If any total coliforms were found in the water sample, then the text lists ‘Present’. In the latter case, a resample is tested for number of total coliforms present. It is important to note that there is no association between the number of total coliforms and disease outbreaks.
EC Presence
Limit = Absent
This column gives the result of the ‘Presence-Absence’ test for E. coli bacteria in water. Rather than enumerating E. coli bacteria, the test indicates only the ‘Presence’ or ‘Absence’ of E. coli in the water. If no E. coli were found then the text lists ‘Absent’. If any E. coli were found in the water sample, then the text lists ‘Present’. It is important to note that no E. coli should be present in treated drinking water as the presence of E. coli indicates recent fecal contamination and the possible presence of enteric pathogens that may adversely affect human health.
TC Background
No Limit
This column gives the result of the non-coliform bacteria (background bacteria) found for that particular sample on that specific date and time. Background bacteria are used as a general measure of the bacterial population present. Under increasing nutrient conditions and/or a reduction in the concentration of chlorine residual, the background bacteria may increase and provide an early warning of the potential growth of coliforms. Health Canada has established that there is no public health significance in finding background bacteria in a water sample.
Colour, True
Limit = 15
This column gives the reading for the presence of colour in the water in “true colour units” (TCU). Colour in drinking water may be due to the presence of coloured inorganic materials such as iron, manganese and copper or organic materials such as tanins and lignins. The presence of colour in drinking water is not directly linked to health. For this reason, the Guidelines for Canadian Drinking Water Quality set only an aesthetic limit of 15 TCU for drinking water.
Turbidity
Limit = 1
This column gives the result for turbidity in the water in nephelometric turbidity unit (NTU) (the current method of choice for turbidity measurement in Canada). The control of turbidity in public drinking water supplies is important for both health and aesthetic reasons.
pH This column gives the pH reading of the drinking water in pH units. The Guidelines for Canadian Drinking Water Quality set an acceptable range for drinking water pH from 6.5 to 8.5 pH units. One of the main reasons for this range of pH in drinking water is to minimize corrosion or incrustation in the pipes, which cause considerable damage to the water supply system. Corrosion of piping materials may become significant below pH 6.5, and the frequency of incrustation and scaling problems may be increased above pH 8.5.
Conductivity This column gives the conductivity reading of the drinking water. Conductivity is a general water quality parameter that indicates the dissolved ions in solution. Conductivity measures the degree of mineralization of the water. As an example, freshly distilled water has a conductivity of 0.5 to 2 uS/cm (micro Siemens per centimetre) whereas Greater Victoria’s drinking water has a conductivity of about 45 uS/cm (an indication that there are more dissolved ions (such as salts) in solution than in distilled water).
Hardness Hardness in water is caused mainly by calcium and magnesium salts (iron and manganese can also contribute). Hard waters have a tendency to form scale deposits and can result in excessive soap consumption. Soft waters, on the other hand, may cause pipe corrosion. Hardness levels between 80 and 100 mg/L provide a balance between corrosion and incrustation.