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 |