The Water Supply (Water Quality) Regulations 2018

Investigations: Schedule 1 parameters

18.—(1) A water undertaker or supplementary licensee must immediately take such steps as are necessary to identify the matters specified in paragraph (2) where it has reason to believe that water of a relevant description—

(a) fails, or is likely to fail, to satisfy a requirement of regulation 4(2);

(b) is to be regarded as unwholesome by virtue of regulation 4(4); or

(c) if regulation 4(6) were ignored, would be regarded as unwholesome by virtue of regulation 4(5).

(2) The matters referred to in paragraph (1) are—

(a) the cause and extent of the failure or, as the case may be, the apprehended failure;

(b) the Schedule 1 parameters in respect of which the prescribed concentration or value has not been, or is unlikely to be, achieved; and

(c) in relation to each parameter so identified, whether the failure, or apprehended failure, to achieve the prescribed concentration or value is attributable—

(i) to the domestic distribution system;

(ii) to the maintenance of that system; or

(iii) to neither of those matters.

(3) Where a departure has been authorised under this Part—

(a) paragraph (1) will apply only in respect of the Schedule 1 parameters (if any) that are not specified in the authorisation; and

(b) every water undertaker or supplementary licensee which has reason to believe that water of a relevant description fails, or is likely to fail, to satisfy the concentration or value required by the authorisation in relation to any Schedule 1 parameter, must immediately take such steps as are necessary to identify the matters specified in paragraph (4).

(4) The matters referred to in paragraph (3) are—

(a) the cause and extent of the failure or, as the case may be, the apprehended failure;

(b) the Schedule 1 parameters in respect of which the required concentration or value has not been, or is unlikely to be, achieved; and

(c) in relation to each parameter so identified, whether the failure, or apprehended failure, to achieve that concentration or value is attributable—

(i) to the domestic distribution system;

(ii) to the maintenance of that system; or

(iii) to neither of those matters.

(5) As soon as possible after the matters specified in paragraph (2) or (4), as the case may be, have been identified, the water undertaker or supplementary licensee must—

(a) notify the Welsh Ministers—

(i) of those matters;

(ii) whether it is its opinion that, in relation to each parameter identified in accordance with paragraph (2)(b) or (4)(b), a failure in respect of that parameter is likely to recur;

(iii) of the action (if any) taken by it in relation to a failure which is attributable to the domestic distribution system or the maintenance of that system; and

(b) send a copy of that notice to any other relevant supplier which uses the supply system for the purposes of supplying water to consumers who are likely to be affected by the failure.

(6) Where the water undertaker or supplementary licensee has identified a failure attributable to the domestic distribution system or to the maintenance of such a system, it must, at the same time as notification is given under paragraph (5)—

(a) by notice in writing—

(i) to those of its consumers who are likely to be affected by the failure; and

(ii) to any other relevant supplier which uses the supply system for the purposes of supplying water to consumers who are likely to be affected by the failure, inform them of the nature of the failure and provide details of the steps (if any) that, in its opinion, it is necessary or desirable for those consumers to take in the interests of their health; and

(b) send a copy of that notice to the Welsh Ministers and to each appropriate local authority.

(7) A relevant supplier which receives a notice under paragraph (6)(a)(ii) must immediately send or cause to be sent a copy of that notice to those of its consumers who are likely to be affected by the failure.

(8) A water undertaker or supplementary licensee which has complied with the requirements of paragraphs (5) and (6) need not, in respect of the same failure or apprehended failure, comply with the requirements of regulation 35(6)(a)(iv).

(9) Where such a failure as is mentioned in paragraph (1) relates to the copper or lead parameter, the relevant supplier must, as soon as reasonably practicable after the occurrence, modify or replace such of its pipes and their associated fittings as it knows or has reason to believe have the potential for contributing to copper or lead in the water supplied to the premises, so as to eliminate that potential (whether or not the presence of copper or lead in those pipes contributed to the failure).