Chief Inspector's Report 2002
25 Yorkshire Water Services Limited
| Overall Water Quality supplied by Yorkshire Water Services Limited in 2002 | |||||||||||||||||||||||
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![Yorkshire Water [Kelda]-MAP](images/Yorkshire-Water-%5BKelda%5D-MAP.gif)
Water Quality at Treatment Works, in Service Reservoirs and in Water Supply Zones
To be wholesome, water must comply with the standards for the parameters set out in the Water Supply (Water Quality) Regulations 1989. In 2002, the Company carried out a total of 266,444 tests on samples taken at water treatment works, from service reservoirs and in water supply zones and of these, 99.89% complied with the relevant water quality standards set down in the Regulations. 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
2002 |
2001 |
2000 |
||
| Number of water treatment works | 102 |
109 |
121 |
|
| COLIFORMS | ||||
| Total number of tests | 10,309 |
10,336 |
12,024 |
|
| - | number containing coliforms | 15 |
4 |
6 |
| - | % containing coliforms | 0.15% |
0.04% |
0.05% |
| Treatment works with coliforms detected | 10 |
3 |
5 |
|
| - | % of all works with coliforms detected | 9.80% |
2.75% |
4.13% |
| FAECAL COLIFORMS | ||||
| Total number of tests | 10,309 |
10,336 |
12,024 |
|
| - | number containing faecal coliforms | 0 |
3 |
3 |
| - | % containing faecal coliforms | 0.00% |
0.03% |
0.02% |
| Treatment works with faecal coliforms detected | 0 |
2 |
2 |
|
| - | % of all works with faecal coliforms detected | 0.00% |
1.83% |
1.65% |
There has been a significant increase since 2001 in the number of treatment works and in the number of tests carried out on samples from treatment works in which total coliforms were detected. However, failures of the coliform standard at eight works were considered trivial. At the other two works, the Company has taken remedial action.
In 2002, 2,674 regulatory samples for Cryptosporidium were taken at eight sites. Very low numbers of oocysts were detected in 16 samples from six sites. All results were well below the treatment standard and there were no reported outbreaks of cryptosporidiosis.
Water Quality in Service Reservoirs
2002 |
2001 |
2000 |
||
| Number of service reservoirs | 414 |
418 |
432 |
|
| COLIFORMS | ||||
| Total number of tests | 20,933 |
21,224 |
21,162 |
|
| - | number containing coliforms | 49 |
39 |
27 |
| - | % containing coliforms | 0.23% |
0.18% |
0.13% |
| Service reservoirs with coliforms detected | 41 |
35 |
25 |
|
| Service reservoirs with coliforms detected | 3 |
1 |
0 |
|
| in more than 5% of tests | ||||
| - | % of all service reservoirs with coliforms detected | 0.72% |
0.24% |
0.00% |
| FAECAL COLIFORMS | ||||
| Total number of tests | 20,933 |
21,225 |
21,162 |
|
| - | number containing faecal coliforms | 11 |
8 |
10 |
| - | % containing faecal coliforms | 0.05% |
0.04% |
0.05% |
| Service reservoirs with faecal coliforms detected | 11 |
8 |
9 |
|
| - | % of all service reservoirs with faecal coliforms detected | 2.66% |
1.91% |
2.08% |
There were failures of the coliform standard at three service reservoirs. However, the failure at one was considered trivial. At the other two service reservoirs the Company has taken action to prevent the failure recurring. Failures of the faecal coliform standard at 11 service reservoirs were considered trivial. 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.
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.
| Parameter | Total number of tests |
Tests not meeting the prescribed concentration or value |
Number of failures covered by Undertakings |
Number of zones not complying with the standards |
|||
No |
% |
2002 |
2001 |
2000 |
|||
Coliforms |
12,572 |
61 |
0.49 |
0 |
0 |
0 |
1 |
Faecal
coliforms |
12,572 |
7 |
0.06 |
0 |
7 |
1 |
8 |
Colour |
12,561 |
0 |
0.00 |
0 |
0 |
1 |
3 |
Turbidity |
12,562 |
2 |
0.02 |
0 |
2 |
9 |
5 |
Odour |
1,622 |
0 |
0.00 |
0 |
0 |
0 |
0 |
Taste |
1,619 |
0 |
0.00 |
0 |
0 |
0 |
0 |
Hydrogen
ion |
12,562 |
6 |
0.05 |
2 |
6 |
0 |
10 |
Nitrate |
1,876 |
1 |
0.05 |
0 |
1 |
2 |
0 |
Nitrite |
1,902 |
8 |
0.42 |
0 |
3 |
5 |
8 |
Aluminium |
6,507 |
12 |
0.18 |
4 |
10 |
4 |
11 |
Iron |
6,507 |
51 |
0.78 |
49 |
38 |
42 |
58 |
Manganese |
6,507 |
15 |
0.23 |
14 |
14 |
13 |
19 |
Lead |
1,023 |
2 |
0.20 |
0 |
2 |
2 |
3 |
PAH |
854 |
5 |
0.59 |
0 |
3 |
0 |
9 |
Trihalomethanes |
943 |
10 |
1.06 |
0 |
3 |
1 |
3 |
Total
pesticides |
1,321 |
0 |
0.00 |
0 |
0 |
4 |
0 |
Clopyralid |
1,054 |
1 |
0.09 |
0 |
1 |
0 |
0 |
2,4-D |
1,138 |
17 |
1.49 |
0 |
17 |
0 |
0 |
Isoproturon |
1,039 |
0 |
0.00 |
0 |
0 |
4 |
4 |
MCPA |
1,131 |
14 |
1.24 |
0 |
14 |
1 |
0 |
Mecoprop |
1,078 |
0 |
0.00 |
0 |
0 |
7 |
0 |
Simazine |
971 |
1 |
0.10 |
0 |
1 |
0 |
0 |
Other
pesticides |
75,331 |
0 |
0.00 |
0 |
0 |
0 |
0 |
All
others |
26,034 |
0 |
0.00 |
0 |
0 |
0 |
0 |
TOTAL |
201,286 |
213 |
0.11% |
69 |
|||
| 205 zones in 2002, 205 zones in 2001, 214 zones in 2000 | |||||||
The fifth column indicates the number of failures in zones already covered by legally binding undertakings given by the Company. These undertakings require remedial work to be carried out to ensure compliance with the individual standard.
The New Regulations
In 2002, the Company carried out monitoring for the six new parametric values set down in the new Water Supply (Water Quality) Regulations 2000. These Regulations come 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 | 1,544 |
1.0 µg/l |
1 |
| Bromate | 664 |
10.0 µg/l |
16 |
| 1,2 dichloroethane | 1,544 |
3.0 mg/l |
0 |
| Nitrite (ex-water treatment works) | 2,212 |
0.1 mg/l |
0 |
| Clostridium perfringens | 192 |
0/100 ml |
0 |
| Enterococci | 766 |
0/100 ml |
1 |
Compliance data for 2002 has also been analysed against the revised standards and the results are shown in the following table.
| Parameter | Total number or tests |
Current Standard |
Number of tests not meeting current standard |
Revised Standard |
Number of tests not meeting revised standard |
|||
| Antimony | 205 |
10.0 µg/l |
0 |
5.0 µg/l |
0 |
|||
| Arsenic | 205 |
50.0 µg/l |
0 |
10.0 µg/l |
0 |
|||
| Boron | 205 |
2.0 mg/l |
0 |
1.0 mg/l |
0 |
|||
| Copper | 824 |
3.0 mg/l |
0 |
2.0 mg/l |
0 |
|||
| Lead | 1,023 |
50.0 µg/l |
2 |
25.0 µg/l1 |
7 |
|||
10.0 µg/l2 |
25 |
|||||||
| Nickel | 205 |
50.0 µg/l |
0 |
20.0 µg/l |
0 |
|||
| Nitrite (at consumers' taps) | 1,902 |
0.1 mg/l |
8 |
0.5 mg/l |
0 |
|||
| PAH | 854 |
0.2 µg/l |
5 |
0.1 µg/l |
0 |
|||
| Tetrachloroethene | 943 |
30.0 µg/l |
|
10.0 µg/l
|
0
|
|||
| Trichloroethene | 943 |
10.0 µg/l |
Details of the new and revised standards, and the reasons for the revisions where applicable, can be found in chapter J "New Regulations and Associated Programmes of Work".
1 From 25.12.03
2 From 25.12.13
Company Audit and Inspection
The Company was inspected or audited by the Inspectorate or its appointed consultants on a number of occasions during 2002. Where relevant, report summaries are available in the 'Business and Technical' section of the Inspectorate's web site under 'Audit and Inspection'.
| Audit or Inspection | Date |
| Audit of regulatory Cryptosporidium monitoring sites | Various dates throughout the year |
| Audit of progress with regulatory programmes of work | March 2002 |
| Review of the distribution system undertaking | July 2002 |
| Inspection of two water treatment works and one service reservoir | June and |
| September 2002 | |
| Unannounced inspection of laboratory analysing for Cryptosporidium | June 2002 |
| Announced inspection of laboratory analysing for Cryptosporidium | August 2002 |
| Audit of response to selected consumer complaints | September 2002 |
| Audit trails of 15 test results | October 2002 |
| Audit of sampling arrangements | November 2002 |
A number of recommendations were made in respect of action required to avoid the risk of a breach of a regulatory duty. These recommendations were in relation to the audit trails, the operation of treatment works and service reservoirs, the programmes of work and the distribution undertaking.
Incidents
The Inspectorate regarded 10 of the events notified during 2002 by the Company as incidents. For further details on the classification of incidents, see chapter C "Events affecting Water Quality" in Part 3.
All of the incidents have been assessed by the Inspectorate. Each was of short duration and Yorkshire Water has taken appropriate remedial action. A number of recommendations were made regarding sampling and procedures.
During the 2002 reporting period, assessment was also completed for three incidents which occurred in 2001.
| Nature of | No. of |
Assessment |
Area affected |
Population |
| incident | incidents |
completed |
potentially |
|
affected |
||||
| Supply of discoloured water | 5 |
Yes |
Harden and |
3,800 |
Cullingworth (March) |
||||
Selby (April) |
50,000 |
|||
Bradford Kirkgate (May) |
3,000 |
|||
Golcar (June) |
3,000 |
|||
Kendray (July) |
72,000 |
|||
| Disinfection failure | 1 |
Yes |
Kepwick (September) |
650 |
| Failure of treatment process | 2 |
Yes |
Kirkhamgate (March) |
0 |
Boltby (September) |
500 |
|||
| Microbiological contamination | 2 |
Yes |
Isle of Axholme (August) |
13,000 |
| of supplies | Wadsley, Sheffield |
100,000 |
||
(September) |
Formal Caution
In January 2003 the Company admitted supplying water unfit for human consumption to consumers in the Sandygates area of Sheffield in June 2001 as a result of deficiencies in planning one stage of a major mains refurbishment programme in the area. The Inspectorate considered that there was sufficient evidence to proceed with a prosecution. However the evidence suggested that the Company took rapid and effective action to address the problem and amended its working procedures following the incident to minimise the risk of a recurrence. A formal caution was therefore considered to be the most appropriate course of action. The caution will remain on the files. Further information can be found in chapter C 'Events affecting Water Quality' in Part 3.
Enforcement Action
The table below indicates areas where, in 2002, 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 |
| Total coliforms | 3(7) | Graincliffe WTW | Remedial action taken |
| Total coliforms | 3(7) | Littleworth WTW | Remedial action taken |
| Trihalomethanes | 3(3)(e) | Oughtershaw | Undertaking submitted |
| water supply zone |
Undertakings and other Improvement Programmes
Water treatment works and service reservoirs
Three undertakings were due for completion during 2002. These were to install treatment at Acomb Landing for pesticides, and in Halifax and Wakefield SAM supply zones for contraventions of the hydrogen ion standard. All the programmes were completed on schedule.
No other improvement programmes were due for completion in 2002.
Distribution
The ongoing distribution system undertaking has been progressing satisfactorily. During 2002, 573.7 km of mains have been renovated. The Company is required to renovate a further 3,944.8 km of mains by March 2010. In addition, one undertaking to remove iron by flushing from the distribution system in York, was due for completion during 2002. This was completed on schedule.
Lead
The Company has a Regulation 41 programme of work to meet the revised standard for lead set down in the new Water Supply (Water Quality) Regulations 2000, which will come into force on 25 December 2003. Progress with the delivery of the programme is monitored by the Inspectorate and has been satisfactory.
