Chemical analysis - Waterloo

The following table shows the mean values of chemical analysis of the water supply from the Waterloo Water Treatment Plant, for the year ended 30 June 2018, compared with the maximum allowable value (MAV) or guideline value (GV) for each element as set out in the Drinking Water Standards New Zealand (DWSNZ).

Notes: (A) MAV denotes the maximum acceptable value to comply with the Drinking-water Standards. (B) GV denotes the maximum guideline value in the Drinking Water Standards

 

Parameter

DWSNZ MAV (A) / GV (B)

No of samples

Median value

Max value

Alkalinity - total g CaCO3/m³

-

13

50.00

62.000

Aluminium - total g/m³

0.1 (B)

15

0.045

0.179

Arsenic - total g/m³

0.01 (A)

2

<0.002

<0.002

Boron - total  g/m³

1.4 (A)

2

<0.05

<0.05

Cadmium - total g/m³

0.004 (A)

2

<0.001

<0.001

Calcium Hardness g CaCO3/m³

-

-

-

-

Chloride g/m³

250 (B)

2

15.850

16.500

Chromium - total g/m³

0.05 (A)

2

<0.001

<0.001

Conductivity at 25°C mS/m

-

2

18.750

20.300

Copper - total g/m³

2 (A)

13

<0.013

<0.013

Cyanide g/m³

0.6 (A)

2

<0.005

<0.005

Fluoride g/m³

-

-

-

-

Hydrogen sulphide g/m³

0.05 (B)

2

<0.05

<0.05

Iron - total g/m³

0.2 (B)

13

0.227

2.000

Lead - total g/m³

0.01 (A)

2

<0.001

<0.001

Manganese - total g/m³

0.04 (A)

13

<0.013

<0.013

Mercury - total g/m³

0.007 (A)

2

<0.001

<0.001

Nickel - total g/m³

0.08 (A)

2

<0.001

<0.001

Nitrate - nitrogen g/m³

50 (A)

2

0.670

0.730

pH

7.0-8.5 (B)

15

7.580

7.900

Selenium - total g/m³

0.01 (A)

2

<0.005

<0.005

Silica g/m³

-

2

15.200

15.900

Sulphate g/m³

250 (B)

2

6.600

7.430

Total dissolved solids g/m³

1000 (B)

2

91.500

99.000

Zinc - total g/m³

1.5 (B)

13

<0.013

<0.013