The Private Water Supplies Regulations 2009

PART 1 Check monitoring

Sampling

1.—(1) A local authority must undertake check monitoring in accordance with this Part.

(2) Check monitoring means sampling for each parameter listed in Table 1 in the circumstances listed in that table in order—

(a) to determine whether or not water complies with the concentrations or values in Schedule 1;

(b) to provide information on the organoleptic and microbiological quality of the water; and

(c) to establish the effectiveness of the treatment of the water, including disinfection.

Table 1

Check monitoring

Parameter	Circumstances
Aluminium	When used as flocculant or where the water originates from, or is influenced by, surface waters
Ammonium	In all supplies
Clostridium perfringens (including spores)	Where the water originates from, or is influenced by, surface waters
Coliform bacteria	In all supplies
Colony counts	In all supplies
Colour	In all supplies
Conductivity	In all supplies
Escherichia coli (E. coli)	In all supplies
Hydrogen ion concentration	In all supplies
Iron	When used as flocculant or where the water originates from, or is influenced by, surface waters
Manganese	Where the water originates from, or is influenced by, surface waters
Nitrate	When chloramination is practised
Nitrite	When chloramination is practised
Odour	In all supplies
Pseudomonas aeruginosa	Only in the case of water in bottles or containers
Taste	In all supplies
Turbidity	In all supplies

Frequency of sampling

2.—(1) Sampling must be carried out at frequencies specified in Table 2.

Table 2

Sampling frequency for check monitoring

Volume m3/day	Sampling frequency per year
≤ 10	1
> 10 ≤ 100	2
> 100 ≤ 1,000	4
> 1,000 ≤ 2,000	10
> 2,000 ≤ 3,000	13
> 3,000 ≤ 4,000	16
> 4,000 ≤ 5,000	19
> 5,000 ≤ 6,000	22
> 6,000 ≤ 7,000	25
> 7,000 ≤ 8,000	28
> 8,000 ≤ 9,000	31
> 9,000 ≤ 10,000	34
> 10,000	4 + 3 for each 1,000 m3/day of the total volume (rounding up to the nearest multiple of 1,000 m3/day)

(2) The local authority may reduce the frequency of sampling for a parameter to a frequency not less than half if—

(a) the local authority is of the opinion that the quality of water in the supply is unlikely to deteriorate;

(b) in the case of hydrogen ion the parameter has had a pH value that is not less than 6.5 and not more than 9.5; and

(c) in all other cases, in each of two successive years the results of samples taken for the purposes of monitoring the parameter in question are constant and significantly lower than the concentrations or values laid down in Schedule 1.

(3) The local authority may set a higher frequency for any parameter if it considers it appropriate taking into account the findings of any risk assessment, and in addition may monitor anything else identified in the risk assessment.