Drinking Water 2003

Water quality at treatment works, in service reservoirs and in water supply zones

To be wholesome, water must comply with the water quality standards for the parameters set out in the Water Supply (Water Quality) Regulations 1989. In 2003, the Company carried out a total of 17,130 tests on samples of water leaving its seven water treatment works, from its 21 service reservoirs and from consumers’ taps in its 16 water supply zones. Of these, 99.82% (17,099) complied with the standards set down in the Regulations. However, 0.18% (31) tests did not meet the standards. A list of the parameters, the relevant standards and their significance can be found at the beginning of this section.

Water quality leaving treatment works

A comparison of the Company’s performance in 2003 with data for 2002 and 2001, is given below. Differences over the last three years in the number of treatment works, and in the number of tests carried out on samples from treatment works, in which coliforms or faecal coliforms were detected, were not considered significant.

During 2003, the single failures of the total coliform standard at three works were considered trivial, or unlikely to recur.

The single failure of the faecal coliform standard at one works was also considered as unlikely to recur.

In 2003, 1,827 regulatory samples for Cryptosporidium were taken at five sites. Very low numbers of oocysts were detected in eight samples from three sites. All results were well below the treatment standard and there were no reported outbreaks of cryptosporidiosis.

Water quality in service reservoirs

A comparison of the Company’s performance in 2003 with data for 2002 and 2001, is given below. Differences over the last three years in the number of service reservoirs, and in the number of tests carried out on samples from service reservoirs, in which coliforms or faecal coliforms were detected, were not considered significant.

During 2003, total coliforms were detected at one service reservoir. However, there were no failures of the total coliform or faecal coliform standard at any service reservoir.

Water quality in water supply zones

The table below shows the data for the key parameters and any other parameters where there was a failure of the standard. All other parameters were fully compliant. A comparison is also given for parameters failing the standards in 2002 and 2001.

Parameter	Total numberof tests	Tests not meeting standard		Number offailures covered by Undertakings	Number of zones not complying with the standards (number of zones in 2003 = 16)*
		No	%		2003	2002	2001
Coliforms	1,184	6	0.51	0	0	0	0
Faecal coliforms	1,184	3	0.25	0	2	0	1
Colour	180	0	0.00	0	0	0	0
Turbidity	180	0	0.00	0	0	0	0
Odour	220	0	0.00	0	0	1	0
Taste	180	0	0.00	0	0	0	0
Hydrogen ion	180	0	0.00	0	0	0	0
Nitrate	180	0	0.00	0	0	0	0
Nitrite	180	0	0.00	0	0	0	3
Aluminium	180	0	0.00	0	0	0	0
Iron	247	3	1.21	0	3	2	5
Manganese	180	0	0.00	0	0	0	0
Lead	80	0	0.00	0	0	0	0
PAH	120	14	11.67	0	4	5	2
Trihalomethanes	79	0	0.00	0	0	0	0
Total pesticides	80	0	0.00	0	0	0	0
Other pesticides	2,347	0	0.00	0	0	0	0
All others	2,394	0	0.00	0	0	0	0
TOTAL	9,375	26	0.28

*15 zones in 2002 and in 2001

The new Regulations

In 2003, the Company carried out monitoring for the six new parametric values set down in the new Water Supply (Water Quality) Regulations 2000. These Regulations came into force on 25 December 2003. The results are shown in the table below.

Parameter	Total number of tests	New standard	Tests not meeting the new standard
Benzene	20	1.0 µg/l	0
Bromate	20	10.0 µg/l	0
1,2 dichloroethane	16	3.0 µg/l	0
Nitrite (exwater treatment works)	20	0.1 mg/l	0
Clostridium perfringens	189	0/100 ml	0
Enterococci	80	0/100 ml	0

Compliance data for 2003 have also been analysed against the revised standards and the results are shown in the following table.

Parameter	Total number of tests	Current Standard	Number of tests not meeting current standard	Revised Standard	Number of tests not meeting revised standard
Antimony	32	10.0 µg/l	0	5.0 µg/l	0
Arsenic	32	50.0 µg/l	0	10.0 µg/l	0
Boron	32	2.0 mg/l	0	1.0 mg/l	0
Copper	80	3.0 mg/l	0	2.0 mg/l	0
Lead	80	50.0 µg/l	0	25.0 µg/l	0
				10.0 µg/l*	1
Nickel	32	50.0 µg/l	0	20.0 µg/l	0
Nitrite (at consumers’ taps)	180	0.1 mg/l	0	0.5 mg/l	0
PAH	227	0.2 µg/l	14	0.1 µg/l	0
Tetrachloroethene Trichloroethane	79 79	10.0 µg/l 30.0 µg/l	0 0	} 10.0 µg/l	0
* Final standard not applicable until 2013

Details of the new and revised standards can be found in chapter J ‘New Regulations and Associated Programmes of Work’.

Audit and inspection

The Company was inspected or audited by the Inspectorate or its appointed consultants on a number of occasions during 2003. Where relevant, report summaries are available in the ‘Business and Technical’ section of the Inspectorate’s website under ‘Audit and Inspection’. Details of the subject areas audited or inspected are given in the following paragraphs:

Follow up of recommendations made during the 2002 inspections or in connection with water quality incidents

Steps have been taken to implement all of the recommendations arising from the 2002 audit and inspection process and from assessments of water quality incidents.

Audit of regulatory Cryptosporidium monitoring sites

The monitoring equipment at all regulatory sites visited during the year was found to be satisfactory.

Audit of regulatory Cryptosporidium samplers

The audit of one of the samplers responsible for taking regulatory Cryptosporidium samples was satisfactory.

Inspection of laboratory analysing for Cryptosporidium

The announced audit on the analytical contractor’s Cryptosporidiu m laboratory identified ten regulatory breaches as well as a number of other minor deficiencies associated with the Standard Operating Protocol. The Company’s analytical contractor has undertaken remedial action to rectify the deficiencies identified.

An unannounced audit on the analytical contractor’s Cryptosporidiu m laboratory was satisfactory.

Audit of progress with water treatment works improvement programmes

A desktop audit of schemes associated with improvement programmes at water treatment works was carried out together with site visits. The schemes were to address Cryptosporidium at Alderney, Knapp Mill, Stanbridge Mill, Woodgreen and Matchams treatment works. Progress with all schemes was considered satisfactory.

Audit trails of selected microbiological test results

Vertical audits were carried out on two test results selected at random for the period October 2002 to February 2003. The Company is being required to take action on deficiencies identified with instrument calibration and records and media on both samples and AQC on one sample.

Audit trails of selected nonmicrobiological test results

Vertical audits were carried out on four test results selected at random for the period December 2002 to March 2003. The Company is being required to take action on deficiencies associated with sample transport paperwork in relation to one sample; and analytical deficiencies identified in respect of its contract laboratory on the method of analysis, the timeliness of the analysis, and the records of analysis in relation to two samples.

Inspection of one water treatment works and four service reservoirs

Inspections were carried out at Alderney water treatment works and four service reservoir sites: Stoney Cross Tower; Nomansland; Beaulieu Hill Top; and Beaulieu RAF Tower. The operation and management of the treatment works were generally satisfactory, however the Company was required to urgently repair a leak on the regulatory Cryptosporidium monitoring point. The operation and management of the service reservoirs were also generally satisfactory, however the Company was required to take action on a number of minor deficiencies associated with: sampling facilities at Beaulieu Hill Top; and pipework at Beaulieu RAF Tower and Stoney Cross Tower.

Audit of procedures relating to mains operations by company and contract staff

Audits of Company procedures were found to be satisfactory.

Audit of sampling arrangements

Audits were carried out on general sampling arrangements and two sample rounds. The Company is required to take action on a number of deficiencies identified on protecting and improving sampling points; the Company’s sampling manual; and training.

Incidents

The Inspectorate regarded one event notified during 2003 as an incident. Further details are given in the table below.

The incident was fully investigated and assessed by the Inspectorate during 2003. It was of relatively short duration and, where applicable, the Company took appropriate action to protect public health.

Nature of incident	Assessment completed during 2003
Discolouration of water supplies
Discolouration of supplies to potentially 5,000 people in Ringwood in June 2003 following planned rezoning of supplies.	Yes

Enforcement action

The table below indicates areas where, in 2003, the Inspectorate considered taking enforcement action for regulatory breaches, and where an undertaking was submitted or where the Company took appropriate action.

Parameter/Area	Regulation breached	Location	Outcome
Analytical deficiencies identified in respect of the Company’s contract laboratory on the method of analysis and the timeliness of the analysis in relation to two samples.	21(2) d		Action taken.

Improvement programmes

Water treatment works/service Reservoirs

No improvement programmes at water treatment works or service reservoirs were due for completion during 2003.