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 165,323 tests on samples of water leaving its 93 water treatment works, from its 311 service reservoirs and from consumers’ taps in its 98 water supply zones. Of these, 99.93% (165,214) complied with the required water quality standards set down in the Regulations. However, 110 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 failures of the total coliform standard at four works were considered trivial, or unlikely to recur.

No failures of the faecal coliform standard occurred at any works.

In 2003, 1,655 regulatory samples for Cryptosporidium were taken at seven sites. Very low numbers of oocysts were detected in 58 samples from seven 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 occasionally detected at a number of service reservoirs. However, there were no failures of the total coliform standard at any service reservoir.

The four failures of the faecal coliform standard at four service reservoirs were considered trivial or unlikely to recur.

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 number of tests	Tests not meeting standard		Number of failures covered by Undertakings	Number of zones not complying with the standards (number of zones in 2003 = 98)*
		No	%		2003	2002	2001
Coliforms	4,712	9	0.19	0	0	0	0
Faecal coliforms	4,712	1	0.02	0	1	0	3
Colour	1,618	0	0.00	0	0	0	0
Turbidity	4,640	2	0.04	0	2	0	4
Odour	236	0	0.00	0	0	0	0
Taste	236	0	0.00	0	0	0	0
Hydrogen ion	4,646	0	0.00	0	0	0	0
Nitrate	4,244	5	0.12	3	4	2	6
Nitrite	4,350	0	0.00	0	0	2	3
Aluminium	1,271	3	0.24	0	2	0	1
Iron	3,688	19	0.52	4	16	21	10
Manganese	4,275	2	0.05	0	1	2	3
Lead	1,659	1	1.81	0	1	1	0
PAH	632	30	0.00	0	19	21	18
Trihalomethanes	361	0	0.00	0	0	0	0
Total pesticides	717	0	0.00	0	0	0	0
Atrazine	486	0	0.00	0	0	2	1
Simazine	486	0	0.00	0	0	0	1
Other pesticides	5,375	0	0.00	0	0	0	0
Ammonium	4,574	1	0.02	0	1	0	0
Cadmium	4,150	1	0.02	0	1	0	0
Phosphorus	188	6	3.19	0	4	1	1
All others	50,646	0	0.00	0	0	0	0
TOTAL	107,902	80	0.07
*98 zones in 2002 and 101 in 2001

 

The fifth column indicates the number of failures in zones already covered by legally binding undertakings given by the Company. These undertakings are given by the Company and require remedial work to be carried out to ensure compliance with the individual standard.

The increase in the number of zones failing to meet the phosphorus standard is due to optimisation of the dosing of phosphate to reduce the plumbosolvent nature of the water to ensure compliance with the new lead tighter standard, which applies from 25 December 2003. However, from this date, the standard for phosphorus no longer applies.

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	New standard	Tests not meeting
	of tests		the new standard
Benzene	265	1.0µg/l	0
Bromate	325	10.0µg/l	0
1,2 dichloroethane	265	3.0µg/l	0
Nitrite (exwater treatment works)	5,506	0.1mg/l	1
Clostridium perfringens	154	0/100ml	1
Enterococci	135	0/100ml	2

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	171		10.0µg/l	0	5.0µg/l	0
Arsenic	171		50.0µg/l	0	10.0µg/l	0
Boron	171		2.0mg/l	0	1.0mg/l	0
Copper	670		3.0mg/l	0	2.0mg/l	0
Lead	1,659		50.0µg/l	1	25.0µg/l	7
					10.0µg/l*	27
Nickel	171		50.0µg/l	0	20.0µg/l	0
Nitrite (at consumers’ taps)		4,350	0.1mg/l	0	0.5mg/l	0
PAH		632	0.2µg/l	30	0.1µg/l	0
Tetrachloroethene Trichloroethene		362 362	10.0µg/l 30.0µg/l	0 0	} 10.0µg/l	0
* Final standard not applicable until 2013

During 2003, the Company had in place a programme of work to meet the revised standard for lead.

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 laboratory analysing for Cryptosporidium

The announced audit on the Company’s Cryptosporidium laboratory identified four regulatory breaches as well as a number of other minor deficiencies associated with the analysis of regulatory samples. The Company has taken remedial action to rectify the deficiencies identified.

An unannounced audit on the Company’s Cryptosporidium laboratory was satisfactory.

Audit of progress with water treatmenter treatment works improvement programmes

A desk top audit of three schemes associated with improvement programmes at water treatment works was carried out together with one site visit. These schemes were for Cryptosporidium at Monkswood (Washpool) treatment works, and for nitrate at Black Lane and Fovant 2 treatment works. General progress was satisfactory although delays had occurred with the scheme at Monkswood (Washpool) which were not within the control of the Company.

Review of distribution system undertaking

Progress with the programme of mains renovation set out in the Company’s continuing distribution system undertaking was found to be satisfactory.

Audit of response to selected consumer complaints

A desk top audit of the Company’s response to 12 consumer complaints about drinking water quality was found to be satisfactory.

Audit trails of selected microbiological test results

Vertical audits were carried out on two test results selected at random for the period December 2002 to March 2003. There were no significant deficiencies identified with the sampling, analysis or reporting.

Audit trails of selected nonmicrobiological test results

Vertical audits were carried out on eight test results selected at random for the period February 2002 to March 2003. The Company is being required to take action on deficiencies identified with the construction of control charts in relation to two parameters and procedures for calibrating thermometers.

Audit of analytical requirements for nitrate and nitrite

Vertical audits were carried out on nitrate and/or nitrite samples taken in a single water supply zone over a six month period to assess any changes in analytical requirements over time. The Company is being required to take action on deficiencies identified with the construction of the control charts.

Audit of Company analytical laboratory

An audit of the Company’s analytical laboratory examined sample reception, sample storage, analytical methods for a number of chemical and microbiological parameters and the Company’s policy and practice regarding internal and external AQC, and basic laboratory calibration. The Company is being required to take action on deficiencies in documentation, AQC practice and calibration procedures.

Inspection of two water treatment works and four service reservoirs

Inspections were carried out at Maundown and Codford water treatment works and Monkton Farleigh, South Hill, Corfe Hills and Lytchett Matravers service reservoir sites. The operation and management of the Monkton Farleigh, South Hill and Lytchett Matravers service reservoirs were satisfactory. However, the Company is being required to take action on a number of minor deficiencies associated with improvements to operations at Maundown water treatment works; improvements to operations and procedures at Codford water treatment works and improvements to the site of Corfe Hills service reservoir.

Audit of sampling arrangements

An audit of one sample round was carried out. The Company is being required to take action on a number of minor deficiencies identified during the round, related to sampler training procedures, transportation of samples and sampling facilities at several sites.

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

Audits of Company procedures were carried out and found to be satisfactory.

Audit of plumbosolvency treatment and control programmes

Progress with the programme of work for plumbosolvency treatment and control measures for lead was found to be satisfactory.

Incidents

The Inspectorate regarded two events notified during 2003 as incidents. Further details of these incidents are given in the table below.

Both of the incidents were fully investigated and assessed by the Inspectorate during 2003. Each was of relatively short duration and the Company took appropriate action to protect public health. The Company was commended for its prompt action in investigating the incident at Exton.

Nature of incident	Assessment completed during 2003
Discoloration of water supplies
Discolouration of supplies to potentially 3,800 consumers in Dancing Hill, North Petherton in January 2003 due to implementation of alternative supply arrangements. Microbiological contamination of water	Yes
Water supplied from a temporary structure at Exton service reservoir to approximately 100 properties for several days in June 2003 contained low levels of coliforms.	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
Iron and Manganese	3(3)(c	Bowden zone	Undertaking Given

Improvement programmes

Water treatment works/service reservoirs

Four undertakings associated with treatment works were due for completion during 2003. These were to install treatment at Black Lane and Clarendon treatment works to remove nitrate, to construct a new reservoir at South Hill to comply with the coliform standard and to investigate the need for treatment in respect of iron in zone 114 Salisbury. All of these undertakings were completed on or ahead of schedule.

Seven statements of intent to reduce the risk of Cryptosporidium breaching the treatment standard were due for completion during 2003. The programmes were completed on schedule.

Three statements of intent for meeting the nitrate standard were due for completion during 2003. The programmes were completed on schedule.

Distribution

Progress for the continuing distribution system undertaking was satisfactory. During 2003, 129 km of mains were renovated. The Company is required to renovate a further 203 km of mains by 31 December 2005.

Lead

The Company’s Regulation 41 programme of work to meet the revised standard for lead set down in the new Water Supply (Water Quality) Regulations 2000 has been progressing satisfactorily. Plumbosolvency treatment measures were installed at all sites specified in the programme by 25 December 2003.