20 SOUTHERN WATER SERVICES LIMITED
Introduction
The Company supplies on average 585 Ml/d of water to a resident population of approximately 2.22 million people in an area covering the Isle of Wight and parts of the counties of Hampshire, Kent and Sussex.
Approximately 70% of the Company’s water resources are derived from ground water sources, mainly from high quality chalk aquifers. The remainder is obtained from surface water sources or combined ground and surface water sources. About 6% of surface water is derived from storage reservoirs.
The Company operates 98 water treatment works. The treated water is distributed via 211 service reservoirs and some 13,302 km of water mains. The Company’s area of supply is divided into 116 water supply zones.
Overall water quality
At water treatment works and service reservoirs and in water supply zones, the Company carried out a total of 77,902 determinations in 2000. Of these, 99.89% demonstrated compliance with the relevant PCV, but 85 showed a contravention to have occurred.
Coliforms were not detected at 93 (95%) of the Company's 98 water treatment works. At all of the Company's 211 service reservoirs, coliforms were absent from at least 95% of samples. Of the Company's 116 water supply zones in 2000, 114 (98%) complied fully with the relevant water quality standards or had breaches of the standards which were either trivial or were fully covered by undertakings. In the other two (2%) of zones, some breaches have resulted in consideration of enforcement action.
Microbiological quality of water leaving treatment works
The Company complied with the sampling frequencies required by regulation 17 at 96 of its 98 treatment works in 2000. Shortfalls at the other two are regarded as trivial.
Table 20.1 shows the Company's performance in 2000, with data for 1999 and 1998 for comparison. Differences over the last three years in the number of treatment works, and samples from treatment works in which coliforms were detected are not considered significant.
All contraventions of the standards at works are considered trivial.
Microbiological quality of water in service reservoirs
The Company complied with the sampling frequencies required by regulation 18 at 210 of its 211 service reservoirs in 2000. The shortfall at the other service reservoir is regarded as trivial.
Table 20.2 shows the Company's performance in 2000, with data for 1999 and 1998 for comparison. Differences the last three years in the number of service reservoirs, and samples from service reservoirs, in which coliforms were detected are not considered significant.
There were no contraventions of the microbiological standards at any of the Company's service reservoirs in 2000.
Water quality in water supply zones
The Company failed to comply with the required sampling frequencies for PAH in nine zones.
Table 20.3 shows the Company's performance in 2000, with data for 1999 and 1998 for comparison. There have been significant reductions over the last three years in the number of zones failing to comply with the standards for iron and PAH. All other differences in zones are not considered significant.
Enforcement action is being considered in respect of some contraventions of standards, as shown in tables 20.3 and 20.4. All other contraventions of the standards in zones are considered trivial or unlikely to recur, or are covered by undertakings.
Inspection
Inspection of work being carried out on the distribution system
Mr O D Hydes, Deputy Chief Inspector, carried out an inspection of a hole in the road at Doomsday Lane Horsham in Southern Water Services Ltd supply area in March 2000. Mr Hydes concluded that:
the site was unattended at the time of the inspection and was in an untidy state with not all pipes having end caps on them. The Company has since confirmed that these were either old pipes of off cuts.
Mr M Morgan, Inspector, carried out an inspection of a hole in the road at Doomsday Lane Horsham in Southern Water Services Ltd supply area in April 2000. Mr Morgan concluded that:
end caps had not been inserted into open ends of mains.
Audit trails of five samples
Mr R M Walls, Consultant, working under the supervision of Mr W M Waite, Principal Inspector, carried out an inspection of the Company in October 2000. Based on Mr Walls' report Mr Waite concluded that:
the sampling arrangements are generally satisfactory, although they could be improved with better records of the conditions of transportation and storage and registration in the analytical laboratory;
the analytical results have appeared on the Public Record in time; and
more attention should be paid to the AQC although some deficiencies have been rectified.
Mr Walls found contraventions of regulation 21(2)(d)(iii) in respect of one parameter. However, remedial action was to be taken speedily in each case and so enforcement action was not necessary.
Audit of plumbosolvency treatment and control programmes of work
In November 2000, Consultants WS Atkins, represented by Mr M Kimber, working under the direction of Mr P Halton, Inspector, carried out an audit of the Company as part of the Inspectorate’s work in agreeing with water companies’ their programmes of works to secure compliance with new lead standards. Based on Mr Kimber’s report, Mr Halton concluded that:
the Company’s process of sites/scheme selection for plumbosolvency treatment and/or optimisation measures is sound;
the integrity of the data submitted to the Inspectorate and used for assessing plumbosolvency was confirmed;
the schemes audited are justified on water quality reasons; and
the Company’s proposed steps to be taken and the proposed completion dates are generally sound.
Follow-up of response (by correspondence only) to recommendations made in 1999 inspection report
Dr K J White, Inspector, carried out an inspection, by correspondence, of Southern Water Services Ltd in October 2000. Dr White concluded that:
the Company had responded generally positively to the recommendations made in 1999, however there was still scope for further improvements in respect of plotting AQC charts.
Review of procedures for operation and maintenance of the distribution network
Mr P Scott, Consultant of Binnie, Black and Veatch, working under the direction of Mr W M Waite, Principal Inspector, carried out an inspection of Southern Water in December 2000. Based on Mr Scott's report Mr Waite concluded that:
the company has made substantial responses to most of the recommendations made in the previous audit of water company procedures for operation and maintenance of distribution systems but there are still areas where the company responses are considered to be inadequate.
Inspection of distribution system improvement programme progress
In September 2000, Consultants Parkman Ltd, represented by Mr G Carlisle, working under the direction of Mr P Halton, Inspector, carried out an audit of the Company’s progress with the mains renovation set out in the distribution Undertaking submitted by the Company. Based on Mr Carlisle’s report, Mr Halton concluded that:
the objectives of the undertaking remained valid;
the steps to be taken were defined with adequate precision;
a practicable timetable had been set; and
the Company was likely to meet the target renovation length by the date for completion of the work.
As a result of these inspections, 19 recommendations were conveyed to the Company for formal response. The Company is taking action or has already taken action on a number of the recommendations.
Improvement programmes
One undertaking in respect of improvement programmes accepted by the Secretary of State from the Company was due for full completion or the completion of major steps during 2000 and it was completed on schedule.
The ongoing distribution system improvement programmes due for completion in 2001, which have been implemented by the Company, have been progressing satisfactorily.
Incidents
Three events notified during 2000 by the Company to the Secretary of State under the terms of the Water Undertakers (Information) Direction 1998 are regarded by the Inspectorate as constituting incidents in which drinking water quality demonstrably deteriorated or in which boil water advice was issued.
In June the Company received complaints of taste and odour from consumers in the Hastings area. The taste and odour was associated with algal growth in impounding reservoirs which was not effectively removed by treatment. Adjustments to the treatment process and to supply arrangements were made and normal water quality was restored.
In November coliforms were detected in the water leaving a water treatment works operated by Folkstone and Dover Water. Southern Water purchase a bulk supply of treated water from this source which is used to supply some consumers in the Napchester area. Southern Water issued advice to boil water to the 130 properties supplied from the source. The Company acted quickly to protect consumers and no contamination was detected in water samples taken from the affected area. Also in November, the Company issued advice to boil water to seven properties in Whitchurch. A repair was being undertaken on the common service pipe to the properties when it was flooded from a nearby collapsed surface water drain. Although the main was isolated at the time, the Company issued precautionary advice to boil water until analysis demonstrated that water quality was satisfactory.
No other events regarded as constituting incidents came to the attention of the Inspectorate in 2000.
No events regarded as constituting incidents in which drinking water quality demonstrably deteriorated came to the attention of the Inspectorate in 2000.
Enforcement action
Table 20.4 summarises enforcement action under consideration for the Company as a result of the Inspectorate's work in, or pertaining to, the calendar year 2000.
table 20.1 Southern Water Services Limited
MICROBIOLOGICAL QUALITY OF WATER LEAVING TREATMENT WORKS2000 1999 1998 Number of water treatment works 98 99 99 Works with no sampling shortfall 96 98 99 COLIFORMS Total number of determinations 8,614 8,736 8,963 - number containing coliforms 5 2 3 - % containing coliforms <0.1 <0.1 <0.1 Treatment works with coliforms detected 5 2 3 - % of all works 4 2 3 FAECAL COLIFORMS Total number of determinations 8,623 8,750 8,963 - number containing faecal coliforms 1 0 0 - % containing faecal coliforms <0.1 0.0 0.0 Treatment works with faecal coliforms detected 1 0 0 - % of all works 0.8 0 0
table 20.2 Southern Water Services Limited
MICROBIOLOGICAL QUALITY OF WATER IN SERVICE RESERVOIRS2000 1999 1998 Number of service reservoirs 211 211 212 Service reservoirs with no sampling shortfall 210 211 211 COLIFORMS Total number of determinations 10,946 10,892 10,876 - number containing coliforms 10 14 7 - % containing coliforms <0.1 0.1 0.1 Service reservoirs with coliforms detected 10 12 6 Service reservoirs with coliforms detected in more than 5% of samples 0 0 0 - % of all service reservoirs 0 0 0 FAECAL COLIFORMS Total number of determinations 10,969 10,907 10,876 - number containing faecal coliforms 0 1 1 - % containing faecal coliforms 0.0 <0.1 <0.1 Service reservoirs with faecal coliforms detected 0 1 1 - % of all service reservoirs 0 <1 <1
table 20.3 Southern Water Limited
WATER QUALITY IN SUPPLY ZONESColumns 'CBU' show, for determinations, contraventions covered by undertakings and, for zones, the total number of zones covered by undertakings in 2000. Column 'E' shows the number of zones for which new enforcement action is under consideration as a result of contraventions of the PCV in 2000. Please refer to the Introduction to Part 2 for more detailed explanation of this table. PARAMETER DETERMINATIONS in 2000 ZONES (116 in 2000)* Total Contravening PCV Non-compliant No. % CBU CBU E Number in: 2000 2000 1999 1998 Coliforms 6,383 20 0.3 0 0 0 0 0 0 Faecal coliforms 6,390 1 <0.1 0 0 0 1 0 1 Colour 872 0 0.0 0 0 0 0 0 0 Turbidity 879 0 0.0 0 0 0 0 1 0 Odour 416 1 0.2 0 0 0 1 0 0 Taste 420 0 0.0 0 0 0 0 0 0 Hydrogen ion 1,095 0 0.0 0 0 0 0 0 0 Nitrate 891 4 0.5 0 0 0 3 0 0 Nitrite 872 0 0.0 0 0 0 0 0 0 Aluminium 873 0 0.0 0 0 0 0 0 0 Iron 1,117 1 <0.1 1 15 0 1 9 11 Manganese 907 0 0.0 0 0 0 0 2 1 Lead 534 1 0.2 0 2 0 1 4 1 PAH 572 35 6.1 32 77 0 20 41 49 Trihalomethanes 479 4 1.0 0 0 1 1 0 0 Total pesticides 270 0 0.0 0 0 0 0 0 0 Chlorthal 0 0 0.0 0 0 0 0 0 2 Other pesticides 5,566 0 0.0 0 0 0 0 0 0 Benzo-3-4-pyrene 570 2 0.3 0 0 0 1 0 0 All others 9,644 0 0.0 0 0 0 0 0 0 TOTAL 38,750 69 0.2 33 - - - - - *116 zones in 1999; 116 zones in 1998
table 20.4 Southern Water Services Limited
SUMMARY OF ENFORCEMENT ACTION CONSIDERED IN 2000Regulation Reason for enforcement 3(3)(c) Contravention of the standard for nitrate in one zone. 3(3)(e) Contravention of the trihalomethane standard in one zone.
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Published 11 July 2001
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