Drinking Water 2003
5 Cholderton and District Water Company Limited
Overall water quality supplied by
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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 605 tests on samples of water leaving its single water treatment works, from its single service reservoir and from consumers’ taps in its single water supply zone. Of these, 99.83% (604) complied with the standards set down in the Regulations. However, 0.17% (one) test 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. There have been no 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.
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During 2003, there were no failures of the total and faecal coliform standards at the Company’s works.
The Company has no sites for regulatory Cryptosporidium monitoring.
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.
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During 2003, there were no failures of the total and faecal coliform standards at the Company’s 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 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 = 1)* |
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|---|---|---|---|---|---|---|---|
|
|
No
|
%
|
|
2003
|
2002
|
2001
|
|
| Coliforms |
15
|
0
|
0.00
|
0
|
0
|
0
|
0
|
| Faecal coliforms |
15
|
0
|
0.00
|
0
|
0
|
0
|
0
|
| Colour |
3
|
0
|
0.00
|
0
|
0
|
0
|
0
|
| Turbidity |
17
|
0
|
0.00
|
0
|
0
|
0
|
0
|
| Odour |
1
|
0
|
0.00
|
0
|
0
|
0
|
0
|
| Taste |
1
|
0
|
0.00
|
0
|
0
|
0
|
0
|
| Hydrogen ion |
17
|
0
|
0.00
|
0
|
0
|
0
|
0
|
| Nitrate |
13
|
0
|
0.00
|
0
|
0
|
0
|
0
|
| Nitrite |
13
|
0
|
0.00
|
0
|
0
|
0
|
0
|
| Aluminium |
4
|
0
|
0.00
|
0
|
0
|
0
|
0
|
| Iron |
14
|
1
|
7.14
|
0
|
1
|
1
|
0
|
| Manganese |
14
|
0
|
0.00
|
0
|
0
|
0
|
0
|
| Lead |
2
|
0
|
0.00
|
0
|
0
|
0
|
0
|
| PAH |
2
|
0
|
0.00
|
0
|
0
|
0
|
0
|
| Trihalomethanes |
1
|
0
|
0.00
|
0
|
0
|
0
|
0
|
| Total pesticides |
13
|
0
|
0.00
|
0
|
0
|
0
|
0
|
| Other pesticides |
78
|
0
|
0.00
|
0
|
0
|
0
|
0
|
| All others |
166
|
0
|
0.00
|
0
|
0
|
0
|
0
|
| TOTAL |
389
|
1
|
0.26
|
|
|
|
|
| *1 zone 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 | 6 | 1.0 µg/l | 0 |
| Bromate | 8 | 10.0 µg/l | 0 |
| 1,2 dichloroethane | 6 | 3.0 µg/l | 0 |
| Nitrite (exwater treatment works) | 12 | 0.1 mg/l | 0 |
| Clostridium perfringens | 6 | 0/100 ml | 0 |
| Enterococci | 5 | 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 |
1
|
10.0 µg/l
|
0
|
5.0 µg/l
|
0
|
| Arsenic |
1
|
50.0 µg/l
|
0
|
10.0 µg/l
|
0
|
| Boron |
1
|
2.0 mg/l
|
0
|
1.0 mg/l
|
0
|
| Copper |
5
|
3.0 mg/l
|
0
|
2.0 mg/l
|
0
|
| Lead |
2
|
50.0 µg/l
|
0
|
25.0 µg/l
|
0
|
|
|
|
|
10.0 µg/l*
|
0
|
|
| Nickel |
1
|
50.0 µg/l
|
0
|
20.0 µg/l
|
0
|
| Nitrite (at consumers’ taps) |
13
|
0.1 mg/l
|
0
|
0.5 mg/l
|
0
|
| PAH |
2
|
0.2 µg/l
|
0
|
0.1 µg/l
|
0
|
|
Tetrachloroethene
Trichloroethene |
1
1 |
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.
Audit trails of selected microbiological test results
A vertical audit was carried out on one test result selected at random for May 2003. The Company is being required to take action on a deficiency identified with the length of incubation.
Audit trails of selected nonmicrobiological test results
Vertical audits were carried out on two test results selected at random for January 2003. No significant deficiencies were identified with the sampling, analysis and reporting.
Inspection of one service reservoir
An inspection was carried out at the Company’s Upper Service Reservoir site. The operation and management of the reservoir were satisfactory but the Company is being required to take action to make some improvements to the site.
Audit of public record
An inspection of the Company’s public record was found to be satisfactory.
Audit of other operational matters
An inspection was made of the Company’s procedures for a number of operational matters. These were generally found to be satisfactory although a number of minor deficiencies were identified for the company to take action on.
Incidents
No incidents were notified by the Company during 2003.
Improvement programmes
The Company has no improvement programmes.
Enforcement action
No enforcement action was considered for the company as a result of Inspectorate activities during 2003.
