# The Water Supply (Water Quality) Regulations 2016, Part 1: Group A and Group B parameters

Extent: E+W

Table 1
Group A parameters and circumstances for monitoring
(1) Item number
(2) Parameter
(3) Circumstances
(1)Sampling for this parameter in water supply zones may be substituted by sampling at supply points.
1
Aluminium
Where used as a water treatment chemical or where the water originates from, or is influenced by, surface waters
2
Ammonium
Where chloramination is practised
3
Coliform bacteria
In all circumstances
4
Colony counts 22°C
In all circumstances
5
Colour
In all circumstances
6
Conductivity
In all circumstances
7
E. coli
In all circumstances
8
Hydrogen ion
In all circumstances
9
Iron
Where used as a water treatment chemical or where the water originates from, or is influenced by, surface waters
10
Manganese
Where the water originates from, or is influenced by, surface waters
11
Nitrate
Where chloramination is practised
12
Nitrite
Where chloramination is practised
13
Odour
In all circumstances
14
Residual disinfectant
In all circumstances
15
Taste
In all circumstances
16
Turbidity
In all circumstances
Table 2
Group B1 parameters and circumstances for monitoring to be used for sampling in water supply zones (or supply points)
(1) Item number
(2) Parameter
(3) Circumstances
(1)Sampling for these parameters may be within water supply zones (Group B1) or at supply points (Group B2).
(2)Monitoring of this parameter in water supply zones is required only where sodium hypochlorite is added after water has left the treatment works. In other circumstances, monitoring is required at supply points (see Group B2).
(3)To monitor for indicative dose.
(4)In the event that a single sample is taken in a year, a further sample must be taken if there is any change in relation to that supply that could affect the concentration of radionuclides in the water supply.
1
Aluminium
Where not used as a water treatment chemical or where the water neither originates from, nor is influenced by, surface waters
2
Ammonium
Where chloramination is not practised
3
Antimony
In all circumstances
4
Arsenic
In all circumstances
5
Benzene
In all circumstances
6
Benzo(a)pyrene
In all circumstances
7
Boron
In all circumstances
8
Bromate
In all circumstances
9
Cadmium
In all circumstances
10
Chloride
In all circumstances
11
Chromium
In all circumstances
12
Clostridium perfringens (including spores)
In all circumstances
13
Copper
In all circumstances
14
Cyanide
In all circumstances
15
1, 2 dichloroethane
In all circumstances
16
Enterococci
In all circumstances
17
Fluoride
In all circumstances
18
Gross alpha
In all circumstances
19
Gross beta
In all circumstances
20
Iron
Where not used as a water treatment chemical or where the water neither originates from, nor is influenced by, surface waters
21
Lead
In all circumstances
22
Manganese
Where the water neither originates from, nor is influenced by, surface waters.
23
Mercury
In all circumstances
24
Nickel
In all circumstances
25
Nitrate
Where chloramination is not practised
26
Nitrite
Where chloramination is not practised
27
Pesticides and related products
In all circumstances
28
Polycyclic aromatic hydrocarbon
In all circumstances
29
Radon
In all circumstances
30
Selenium
In all circumstances
31
Sodium
In all circumstances
32
Sulphate
In all circumstances
33
Tetrachloroethene
In all circumstances
34
Tetrachloromethane
In all circumstances
35
Total organic carbon
In all circumstances
36
Trichloroethene
In all circumstances
37
Trihalomethanes: Total
In all circumstances
38
Tritium
In all circumstances
Table 3
Group B2 parameters and circumstances for monitoring to be used for sampling at works or in water supply zones (or supply points)
(1) Item number
(2) Parameter
(3) Circumstances
(1)Sampling for these parameters may be within water supply zones (Group B1) or at supply points (Group B2).
(2)Monitoring is required at supply points where sodium hypochlorite is not added after water has left the treatment works. In other circumstances, see Group B1.
(3)To monitor for indicative dose.
(4)In the event that a single sample is taken in a year, a further sample must be taken if there is any change in relation to that supply that could affect the concentration of radionuclides in the water supply.
1
Benzene
In all circumstances
2
Boron
In all circumstances
3
Bromate
In all circumstances
4
Chloride
In all circumstances
5
Clostridium perfringens (including spores) (1)
In all circumstances
6
Cyanide
In all circumstances
7
1, 2 dichloroethane
In all circumstances
8
Fluoride
In all circumstances
9
Gross alpha
In all circumstances
10
Gross beta
In all circumstances
11
Indicative dose (1)
In all circumstances
12
Mercury
In all circumstances
13
Nitrite
When chloramination is not practised
14
Pesticides and related products
In all circumstances
15
Radon
In all circumstances
16
Sulphate
In all circumstances
17
Tetrachloroethene/Trichloroethene (1)
In all circumstances
18
Tetrachloromethane
In all circumstances
19
Total organic carbon
In all circumstances
. . .
. . .
. . .
21
Tritium
In all circumstances
Table 4
Group A1 parameters
(1) Item number
(2) Parameter
1
Coliform bacteria
2
E. coli
3
Residual disinfectant
Table 5
Group A2 parameters
(1) Item number
(2) Parameter
1
Coliform bacteria
2
Colony counts 22°C
3
E. coli
4
Nitrite
5
Residual disinfectant
6
Turbidity
Table 6
Group A3 parameters
(1) Item number
(2) Parameter
1
Conductivity
Table 7
Group A4 parameters
(1) Item number
(2) Parameter
1
Aluminium
2
Ammonium
3
Colony counts 22°C
4
Colour
5
Conductivity
6
Hydrogen ion
7
Iron
8
Manganese
9
Nitrate
10
Nitrite
11
Odour
12
Taste
13
Turbidity

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Source: https://www.legislation.gov.uk/uksi/2016/614/schedule/3/part/1 (the official version)
Page: https://openlegislation.uk/water-supply-water-quality-regulations-2016/schedule-3/part-1
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.