The Water Supply (Water Quality) Regulations 2018

Regulations 2, 6, 8 and 9

SCHEDULE 3 MONITORING

Part 1 Group A and Group B Parameters

Table 1

Group A parameters and circumstances for monitoring

Item number (1)	Parameter (2)	Circumstances (3)
(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(1)	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
Note:

Table 2

Group B1 parameters and circumstances for monitoring to be used for sampling in water supply zones (or supply points)

Item number	Parameter (2)	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— (i) not used as a water treatment chemical; or (ii) 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 (1)	In all circumstances
6	Benzo(a)pyrene	In all circumstances
7	Boron (1)	In all circumstances
8	Bromate (2)	In all circumstances
9	Cadmium	In all circumstances
10	Chloride (1)	In all circumstances
11	Chromium	In all circumstances
12	Clostridium perfringens (including spores)	In all circumstances
13	Copper	In all circumstances
14	Cyanide (1)	In all circumstances
15	1, 2 dichloroethane (1)	In all circumstances
16	Enterococci	In all circumstances
17	Fluoride (1)	In all circumstances
18	Gross alpha (1) (3) (4)	In all circumstances
19	Gross beta (1) (3) (4)	In all circumstances
20	Iron	Where— (i) not used as a flocculant; or (ii) 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 (1)	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 (1)	In all circumstances
28	Polycyclic aromatic hydrocarbon	In all circumstances
29	Radon (1) (4)	In all circumstances
30	Selenium	In all circumstances
31	Sodium	In all circumstances
32	Sulphate (1)	In all circumstances
33	Tetrachloroethene (1)	In all circumstances
34	Tetrachloromethane (1)	In all circumstances
	Total organic carbon (1)
35	Trichloroethene	In all circumstances
	Trihalomethanes: Total
36	Tritium (1) (4)	In all circumstances
Notes:

Table 3

Group B2 parameters and circumstances for monitoring to be used for sampling at works or supply points

Item number	Parameter (2)	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 (1)	In all circumstances
2	Boron (1)	In all circumstances
3	Bromate (2)	In all circumstances
4	Chloride (1)	In all circumstances
5	Clostridium perfringens (including spores)	In all circumstances
6	Cyanide (1)	In all circumstances
7	1, 2 dichloroethane (1)	In all circumstances
8	Fluoride (1)	In all circumstances
9	Gross alpha (1) (3) (4)	In all circumstances
10	Gross beta (1) (3) (4)	In all circumstances
11	Indicative dose	In all circumstances
12	Mercury (1)	In all circumstances
13	Nitrite	When chloramination is not practised.
14	Pesticides and related products (1)	In all circumstances
15	Radon (1) (4)	In all circumstances
16	Sulphate (1)	In all circumstances
17	Tetrachloroethene (1)	In all circumstances
18	Tetrachloromethane (1)	In all circumstances
19	Total organic carbon (1)
20	Trichloroethene	In all circumstances
21	Tritium (1) (4)	In all circumstances
Notes:

Table 4

Group A1 parameters

Item number	Parameter
1	Coliform bacteria
2	E. coli
3	Residual disinfectant

Table 5

Group A2 parameters

Item number	Parameter
1	Coliform bacteria
2	Colony counts 22° C
3	E.coli
4	Nitrite
5	Residual disinfectant
6	Turbidity

Table 6

Group A3 parameters

Item number	Parameter
1	Conductivity

Table 7

Group A4 parameters

Item number	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

PART 2 Annual sampling frequencies: water supply zones

Table 8

Annual sampling frequencies for Group A4 parameters: water supply zones

Note:

This table and each table which follows it in this Part set out the annual sampling frequencies for all the substances and parameters comprising each of the groups to which they correspond, those groups having been outlined in Part 1 of this Schedule. These are determined for each water supply zone according to its estimated population (as specified in column one of each table in this Part). The number of samples to be taken is the standard number specified in column 2, unless a notice varying this number has been given under regulation 9.

Estimated population of water supply zone	Standard sampling frequency per year
<100	2
100-4,999	4
5,000—9,999	12
10,000-29,999	24
30,000-49,999	36
50,000-79,999	52
80,000-100,000	76

Table 9

Annual sampling frequencies for Group B1 parameters: water supply zones

Estimated population of water supply zone	Standard sampling frequency per year
<100	1
100-4,999	4
5,000-100,000	8

Table 10

Annual sampling frequencies for Group A1: water supply zones

Estimated population of water supply zone	Standard sampling frequency per year
<100	4
≥100	12 per 5,000 population

Note:

For the purposes of this Table, where the population is not an exact multiple of 5,000, the population figure must be rounded up to the nearest multiple of 5,000.

PART 3 Annual sampling frequencies: treatment works and supply points

Table 11

Annual sampling frequencies for Group A2 parameters: treatment works or supply points

Note: This table and each table which follows it in this Part set out the annual sampling frequencies for all the substances and parameters comprising each of the groups to which they correspond at treatment works or supply points, those groups having been outlined in Part 1 of this Schedule. The frequencies are determined according to the volume of water supplied at each treatment works or supply point. The number of samples to be taken is the standard number specified in column 2, unless a notice varying this number has been issued under regulation 9.

Volume of water supplied m 3/day	Standard sampling frequency per year
<20	4
20-1,999	52
2,000-5,999	104
6,000-11,999	208
≥12,000	365

Table 12

Annual sampling frequencies for Group A3 parameters: treatment works or supply points

Volume of water supplied m 3/day	Standard sampling frequency per year
<20	2
20-999	4
1,000-1999	12
2,000-5,999	24
6,000-9,999	36
10,000-15,999	52
16,000-32,999	104
33,000-49,999	156
50,000-67,999	208
68,000-84,999	260
85,000-101,999	312
102,000-119,999	365
120,000-241,999	730
242,000-484,999	1,460
485,000-728,999	2,190

Table 13

Annual sampling frequencies for Group B2 parameters: treatment works or supply points

Volume of water supplied m 3/day	Standard sampling frequency per year
<20	1
20-999	4
1,000-49,999	8
50,000-89,999	12
90,000-299,999	24
300,000-649,999	36
≥650,000	48