# The Water Supply (Water Quality) (Scotland) Regulations 1990, Regulation 17: Sampling at treatment works


(1) Subject to paragraphs (2) to (4), in each year a water authority 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) In the period from 1st July 1990 to 31st December 1990, the number of samples taken shall be not less than one-half of the standard number, which number shall be rounded upwards, if necessary, to the nearest whole number.
(3) 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 apply in order to determine the number of samples to be taken in 1991, 1992 and 1993 with the modifications specified in paragraph (4) below.
(4) Paragraph (3) shall apply in order to determine the number of samples to be taken—
(a) in 1991 as if it referred to the period from 1st July 1990 to 31st December 1990 instead of three successive years;
(b) in 1992 as if it referred to the period from 1st July 1990 to 31st December 1991 instead of three successive years;
(c) in 1993 as if it referred to the period from 1st July 1990 to 31st December 1992 instead of three successive years; and
(d) in each of these years with the substitution of “paragraphs (1) and (2)” for “paragraph (1)”.
(5) A reduced number of samples may be taken in accordance with paragraph (3) in respect of works supplying for domestic purposes an average volume of more than 2,000m3/d of water only if the water authority 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.

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Source: https://www.legislation.gov.uk/uksi/1990/119/regulation/17 (the official version)
Page: https://openlegislation.uk/water-supply-water-quality-scotland-regulations-1990/regulation-17
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.