1 ANGLIAN WATER SERVICES LIMITED
Introduction
Anglian Water Services Limited supplies on average approximately 1,200 Ml/d to a resident population of about four million. The area of supply covers East Anglia, Lincolnshire, Bedfordshire, Northamptonshire and parts of Essex, Buckinghamshire and Nottinghamshire. About 47% of the Company’s water supplies come from storage reservoirs, 50% from aquifers and 3% from rivers. Water is treated at 139 treatment works and is distributed via 380 service reservoirs and 35,233 km of mains. The supply area is divided into 189 zones.
Overall water quality
At water treatment works and service reservoirs and in water supply zones, the Company carried out a total of 208,630 determinations in 2000. Of these, 99.63% demonstrated compliance with the relevant PCV, but 776 showed a contravention to have occurred.
Coliforms were not detected at 132 (95%) of the Company's 139 water treatment works. At all of the Company's 380 service reservoirs, coliforms were absent from at least 95% of samples. Of the Company's 189 water supply zones in 2000, 188 (99%) 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 zone, some breaches are regarded as trivial, but others could result in enforcement action.
Microbiological quality of water leaving treatment works
The Company complied with the sampling frequencies required by regulation 17 at all its treatment works in 2000.
Table 1.1 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 treatment works are considered trivial.
Microbiological quality of water in service reservoirs
The Company complied with the sampling frequencies required by regulation 18 at all of its service reservoirs in 2000.
Table 1.2 shows the Company's performance in 2000, with data for 1999 and 1998 for comparison. There has been a significant decrease since 1999 in the number of service reservoirs, and samples from service reservoirs, in which faecal coliforms were detected. All other differences at service reservoirs were not considered significant.
All contraventions of the standards at service reservoirs are considered trivial.
Water quality in water supply zones
The Company failed to comply with the required sampling frequency for taste and odour parameters in one zone. This is unlikely to recur as the Company has taken action to amend the sampling programme.
Table 1.3 shows the Company's performance in 2000, with data for 1999 and 1998 for comparison. There has been a significant decrease since 1999 in the number of zones failing to comply with the standard for iron. All other differences in water supply zones were not considered significant.
Enforcement action is being considered in respect of some contraventions of standards, as shown in tables 1.3 and 1.4. All other contraventions of the standards in zones are considered trivial or unlikely to recur, or are covered by undertakings.
Inspection
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.
Audit trails of five samples
Mr R M Walls, Consultant, working under the direction of Mr W M Waite, Principal Inspector, carried out an inspection of Anglian Water Services Ltd in a visit in November 2000. Based on his report Mr Waite concluded that:
The sampling and analytical arrangements are generally satisfactory although a number of minor irregularities were found. Action has already been taken to prevent a recurrence. The analytical results have appeared on the Public Record in time.
Follow-up of response to recommendations and inspection of service reservoirs
Dr K J White, Inspector, carried out an inspection of Anglian Water Services Ltd in a visit in November 2000. Dr White concluded that:
the Company has made a positive response to the recommendations made in previous inspection reports and reports on an incident and consumer complaint;
the three sites which comprise Warren Hill service Reservoirs numbers 1-3 are in very good secure condition and adequate measures have been taken to protect the security of the sites and hence the quality of the supply of drinking water;
the three service reservoirs have been subject to a regular planned maintenance programme;
the compliance monitole 2ring taps at each service reservoir are of suitable construction and in satisfactory condition to ensure proper delivery of samples for the purpose regulatory compliance monitoring;
there is a formal policy within the Company promote efficient turnover/circulation of water within service reservoir and water storage points. This policy is actively implemented;
the Company is actively improving the quality of the level probes it uses and has a routine maintenance programme in place;
the Company has been pursuing a programme of work at all its sites to meet the criteria laid down in the Code of Practice for the Security of Service Reservoirs. Further work remains to be done subject to board approval being given; and
that as far as practicable at Warren Hill reservoirs numbers 1-3 measures have been implemented to meet the required basic level of protection as defined in the Code of Practice for the Security of Service Reservoirs.
Inspection of distribution system improvement programme progress
Consultants John Champion Ltd, represented by Mr W Eden and working under the direction of Mr P Halton, Inspector, made three visits to the Company between September 2000 and January 2001 to carry 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 Eden’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, two recommendations were conveyed to the Company for formal response. The Company is taking action or has already taken action on the recommendations.
Improvement programmes
No undertakings in respect of improvement programmes accepted by the Secretary of State from the Company were due for full completion or the completion of major steps during 2000.
The ongoing distribution system improvement programmes due for completion in 2002, which have been implemented by the Company, have been progressing satisfactorily.
Relaxations
The Secretary of State had authorised relaxations of the PCV for potassium in zones supplied from five works and for sulphate in zones supplied from one other works subject to review by 31 December 1999. As a result of the review the relaxations were renewed subject to a further review in December 2003.
Incidents
Eighteen of the events notified during 2000 by the Company to the Secretary of State under the terms of the Water Undertakers (Information) Direction 1998 were regarded by the Inspectorate as constituting incidents in which drinking water quality demonstrably deteriorated.
Fifteen incidents have been assessed. Twelve of these involved the supply of discoloured water. Areas affected were parts of Harleston in March, June, August and October; Downham Market in March; Long Stratton and Halstead in July; Donnington and Hadleigh in September; Corby in October; and Moulton and Grantham in November. Two incidents involved wholesomeness concerns after low level bacteriological failures following burst mains in Grantham and Welton in November and one an adverse taste and odour following back siphonage in Beetley in January. In each of the above incidents the problem was of short duration and the Company took effective remedial action.
Three incidents remain under consideration. Two of these relate to the supply of discoloured water and one involved wholesomeness concerns following raw water deterioration after flooding.
No other events regarded as constituting incidents came to the attention of the Inspectorate in 2000.
Enforcement action
Table 1.4 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 1.1 Anglian Water Services Limited
MICROBIOLOGICAL QUALITY OF WATER LEAVING TREATMENT WORKS2000 1999 1998 Number of water treatment works 139 140 134 Works with no sampling shortfall 139 140 134 COLIFORMS Total number of determinations 14,768 14,645 15,093 - number containing coliforms 7 8 3 - % containing coliforms <0.1 <0.1 <0.1 Treatment works with coliforms detected 7 7 3 - % of all works 5.0 5.0 2.2 FAECAL COLIFORMS Total number of determinations 14,768 14,645 15,093 - number containing faecal coliforms 0 0 1 - % containing faecal coliforms 0.0 0.0 <0.10 Treatment works with faecal coliforms detected 0 0 1 - % of all works 0.0 0.0 <0.1
Table 1.2 Anglian Water Services Limited
MICROBIOLOGICAL QUALITY OF WATER IN SERVICE RESERVOIRS2000 1999 1998 Number of service reservoirs 380 385 386 Service reservoirs with no sampling shortfall 380 384 385 COLIFORMS Total number of determinations 20,464 20,540 20,735 - number containing coliforms 31 29 23 - % containing coliforms 0.2 0.1 0.1 Service reservoirs with coliforms detected 26 25 20 Service reservoirs with coliforms detected in more than 5% of samples 0 1 1 - % of all service reservoirs 0.0 <1 <1 FAECAL COLIFORMS Total number of determinations 20,464 20,540 20,735 - number containing faecal coliforms 1 7 5 - % containing faecal coliforms <0.1 <0.1 <0.1 Service reservoirs with faecal coliforms detected 1 7 5 - % of all service reservoirs 0.3 2 1
Table 1.3 Anglian Water Services 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 (189 in 2000)* Total Contravening PCV Non-compliant No. % CBU CBU E Number in: 2000 2000 1999 1998 Coliforms 13,225 38 0.3 0 0 0 0 0 0 Faecal coliforms 13,325 5 <0.1 0 0 0 5 4 1 Colour 2,449 0 0.0 0 0 0 0 0 0 Turbidity 9,194 3 <0.1 1 37 0 3 9 9 Odour 832 1 0.1 0 0 0 1 0 0 Taste 821 1 0.1 0 0 0 1 0 0 Hydrogen ion 9,190 0 0.0 0 0 0 0 0 0 Nitrate 3,512 7 0.2 0 0 1 1 1 0 Nitrite 4,777 626 13.1 0 0 0 59 55 58 Aluminium 2,639 0 0.0 0 0 0 0 0 0 Iron 5,406 24 0.4 21 132 1 18 29 33 Manganese 2,860 0 0.0 0 18 0 0 2 6 Lead 1,266 0 0.0 0 0 0 0 0 4 PAH 455 27 6.0 19 42 0 15 17 18 Trihalomethanes 337 0 0.0 0 0 0 0 0 0 Total pesticides 1,975 0 0.0 0 0 0 0 0 0 Other pesticides 23,768 0 0.0 0 0 0 0 0 0 Ammonium 2,579 1 <0.1 0 0 0 1 1 0 Copper 983 1 0.1 0 0 0 1 0 0 Nickel 247 0 0.0 0 0 0 0 0 1 Phosphorous 3,480 1 <0.1 0 0 0 1 0 0 Potassium 1,170 0 0.0 0 0 0 0 1 0 Temperature 12,912 0 0.0 0 0 0 0 1 0 Total Hardness 229 2 0.9 0 0 0 1 1 0 All others 20,435 0 0.0 0 0 0 0 0 0 TOTAL 138,166 737 0.5 41 - - - - - *194 zones in 1999; 193 zones in 1998.
Table 1.4 Anglian Water Services Ltd
SUMMARY OF ENFORCEMENT ACTION CONSIDERED IN 2000Regulation Reason for enforcement 3(3)(c) Contravention of the standard for iron in one zone. 3(c)(c) Contravention of the standard for nitrate in one zone.
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Published 11 July 2001
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