The Water Supply (Water Quality) Regulations 1989

PART V MONITORING— ADDITIONAL PROVISIONS

Interpretation

15.  In this Part–

“the standard number” means such number specified in the column headed “Standard” in Table 7 as is applicable to the parameter in question by reference to the volume of water supplied for domestic purposes from the relevant water supply zone during the preceding year; and

“reduced number” means the relevant reduced number (if any) shown in Table 7.

Sampling for particular parameters

16.  For the purpose of establishing the quality of water to be supplied to any of its water supply zones, a water undertaker shall take and analyse or cause to be analysed, such number of samples as is so specified.

Sampling at treatment works

17.—(1) Subject to paragraphs (2) to (4), in each year a water undertaker shall take from the point at which water leaves each treatment works which serves its water supply zones for analysis for testing for compliance with the parameters mentioned in Table 7 not less than the standard number of samples.

(2) Where in each of three successive years the result of the analysis of the samples taken in accordance with paragraph (1) has established an absence of faecal and total coliforms and no significant increase in colony counts, the number of samples to be taken in the next following year from the point at which water leaves that works in respect of those parameters or that parameter, as the case may be, may, subject to paragraph (5), be the reduced number:

Provided that this paragraph shall not apply where the following year is 1990 and shall apply where the following year is 1991 or 1992 with the modifications specified in paragraph (3) below.

(3) Paragraph (2) shall apply–

(a) where the following year is 1991 as if it referred to 1990 instead of three successive years;

(b) where the following year is 1992 as if it referred to two years instead of three years.

(4) The number of samples to be taken in 1990 in respect of any parameter mentioned in Table 7 may, if on the application of the water undertaker the Secretary of State so authorises, be the reduced number.

(5) A reduced number of samples may be taken in accordance with paragraph (2) in respect of works supplying for domestic purposes an average volume of more than 2,000 m³/d of water only if the water undertaker is of the opinion that there is no foreseeable risk that faecal or total coliforms will be present in the supply or the works are so designed that a failure of the disinfection process will bring about automatically a cessation of the supply.

Sampling at service reservoirs

18.  A water undertaker shall take from each of its service reservoirs at least one sample for analysis for testing for compliance with each of the parameters listed in Table 7 in each week in which the reservoir is in use.

Sampling—additional samples

19.—(1) If, as a consequence of any change in a water undertaker’s practices in treating water at a treatment works or service reservoir, the undertaker is of the opinion that the prescribed concentration or value in respect of any parameter mentioned in Tables 1 to 5 has been or may be contravened, it shall until the end of the next following year (or for such other period as the Secretary of State may notify to the undertaker in writing) take for analysis for testing for compliance with that parameter the number of samples specified in paragraph (2).

(2) The number of samples to be taken is–

(a) for any whole year in the period, the increased corresponding number specified in the relevant Table for that parameter or (where none is specified) the standard number;

(b) for any other period, the appropriate increased corresponding number multiplied by the number of whole months in the period and divided by 12; and, where the result is not a whole number, rounded upwards to the nearest whole number.

(3) Where an analysis of samples taken in accordance with paragraph (1) demonstrates that there has been no contravention of the prescribed concentration or value in the relevant period, the undertaker may revert to sampling in accordance with regulation 13(1).

Sampling—new sources

20.—(1) This regulation applies as respects–

(a) any source which has not been used for the supply of water by a statutory water company, a water authority or a water undertaker at any time since 15th July 1985; and

(b) any source which has been so used but not so used for a period of six months preceding the date on which the water undertaker proposes to supply water from it.

(2) A water undertaker shall–

(a) before it supplies water from a source mentioned in paragraph (1)(a); and

(b) as soon as is reasonably practicable after it has begun to supply water from a source mentioned in paragraph (1)(b),

take in accordance with paragraph (3) such samples of that water as will enable it to establish–

(i) whether water can be supplied from that source without contravening section 52(1) of the Act; and

(ii) the treatment necessary to ensure that section 52(1) is complied with in relation to the supply of that water.

(3) Samples shall be taken–

(a) in the case of a source mentioned in paragraph (1)(a), in respect of–

(i) each of the parameters listed in Schedule 2; and

(ii) any other element, organism or substance which, in the opinion of the undertaker, may cause the supply to contravene section 52(1); or

(b) in the case of a source mentioned in paragraph (1)(b), in respect of–

(i) the parameters listed in Table C;

(ii) any parameter by reference to which an assessment may be made of the balance of ions within the water; and

(iii) any other parameter whose concentration or value may, in the opinion of the water undertaker, have altered since the last occasion on which water from that source was analysed.

Collection and analysis of samples

21.—(1) A water undertaker shall secure, so far as is reasonably practicable, that in taking, handling, transporting, storing and analysing or causing to be analysed any sample taken for the purposes of Parts IV and V of these Regulations, the appropriate requirements are satisfied.

(2) In paragraph (1) “the appropriate requirements” means such of the following requirements as are applicable–

(a) the sample is representative of the quality of the water at the time of sampling;

(b) the sample is not contaminated when being taken;

(c) the sample is kept at such temperature and in such conditions as will secure that there is no material alteration of the concentration or value for the measurement or observation of which the sample is intended;

(d) the sample is analysed as soon as may be after it has been taken–

(i) by or under the supervision of a person who is competent to perform that task;

(ii) with the use of such equipment as is suitable for the purpose;

(iii) by applying such analytical systems and methods as are capable of establishing, within acceptable limits of deviation and detection, whether the sample contains concentrations or values which contravene the prescribed concentrations or values; and

(e) any laboratory at which samples are analysed has a system of analytical quality control that is subjected from time to time to checking by a person who is–

(i) not under the control of either the laboratory or the undertaker; and

(ii) approved by the Secretary of State for that purpose.