Information Letter
|
|
Drinking Water Inspectorate |
11 September 2006
Information Letter 9/2006
To: Board Level and
Day to Day Contacts of Water and Sewerage Companies and Water Companies in England and
Wales, in-situ resin lining manufacturers and contractors.
Dear Sir/Madam
Update
on the in-situ resin lining of water mains under Regulation 31 (10) (b) of the
Water Supply (Water Quality) Regulations 2000 (2001 Wales)
This letter provides details of changes to the in situ lining
of water mains and provides clarification on the role that DWI will take from 1 January
2007. The letter has been separated into three parts:
- Notification of DWI’s withdrawal as nominator of certifying bodies and management of the Operational Requirements and Code of Practice.
- Update to the Operational Requirements and Code of Practice for the In-Situ Resin Lining of Water mains.
- Determination of
Minimum Spin-Up Time and Adequate Mixing.
Each of these subsections is presented with supporting information below and in the associated Appendices A-D.
1. Notification
of DWI’s withdrawal as nominator of certifying bodies and management of the
Operational Requirements and Code of Practice
Currently the DWI publishes a list of
nominated certifying bodies capable of accrediting resin lining contractors and equipment.
It also manages the new Operational Requirements: In-situ Resin Lining of Water
Mains and Code of Practice: In Situ Lining of Water Mains. Since the issue of
Regulation 31 Letter 03/2005 it has been established that it is inappropriate for DWI to
manage nominated bodies to accredit contractors due to a potential conflict of interest
with DWI’s enforcement role, in particular its role as taking forward a prosecution
under Section 70 of the Water Industry Act 1991, or a prosecution under Regulation 33(3)
for an offence under Regulation 31, or enforcement action under Section 18 of the Water
Industry Act 1991 for a contravention of Regulation 31 relating to relined water
mains.
With effect from 31 December 2006, the DWI
will no longer be nominating certifying bodies and the Operational Requirements will be
amended to reflect this change. It will be the responsibility of each company to ensure
that it introduces processes and procedures that will ensure there is no impact upon water
quality of in-situ lining. The
Operational Requirements: In-situ Resin Lining of Water Mains and Code of
Practice: In Situ Lining of Water Mains will similarly no
longer be the responsibility of the DWI from the same date. This was communicated to the
industry at a meeting on 18 July 2006. Further
details of the information tabled and associated responsibilities can be found in Appendix A. From 1 January 2007 there will be no DWI
Nominated Certifying Bodies and therefore accreditation through these bodies will not be
acceptable. The industry should therefore ensure that a replacement scheme is in place by
this date.
2. Update
to the Operational Requirements and Code of Practice for the In-Situ Resin Lining
of Water mains
Regulation 31 letter 03/2005 gave note of
the intention to modify conditions of approval to in-situ coatings. A copy of this
letter can be used by following the following link ( Regulation 31 letter 03/2005 Notice of
intention to modify conditions of approval of in situ coatings). The Inspectorate had
previously stated that the document would be updated when appropriate. Since this letter a
number of comments have been fed back to the Inspectorate and expert opinion has been
sought. The Inspectorate felt it appropriate to review these comments as it had agreed,
prior to handing over the management of the documents.
The Inspectorate therefore wishes to inform you that changes have been made to the Operational Requirements: In-situ Resin Lining of Water Mains and Code of Practice: In Situ Lining of Water Mains. These documents are posted on the DWI website at: www.dwi.gov.uk/cpp/neworcopindex.shtm. A summary of the comments and feedback, along with the decision made has been detailed in Appendix B. These changes will come into force on 1 April 2007.
3. Determination
of Minimum Spin-Up Time and Adequate Mixing
The Inspectorate therefore required lining
manufacturers to be able to confirm the appropriate spin-up time and in line mixer length
to ensure that mixing is satisfactory. An appropriate safety margin with a view to the
spin-up time and mixer length should be specified for various rig/material combinations.
This research should be conducted by all lining manufacturers in consultation with the
lining contractors and be completed by January 1st 2007.
To date the Inspectorate has only been made aware of one manufacturer conducting such research, though it recognises that the date for completion of this work has not yet been reached. The Inspectorate therefore considered it prudent to inform all manufacturers, contractors and water companies that should relining be undertaken after 1 January 2007 without documented evidence of adequate mixing then the inspectorate will interpret this as the company committing an offence of using an unapproved material and will prosecute under Regulation 31(10)(b).
4. Further
Information
Copies of this letter are being sent to
Pamela Taylor, Chief Executive, Water UK; Richard Wood, Water Supply and Regulation
Division, Department for Environment, Food and Rural Affairs; June Milligan, Environment
Division, Welsh Assembly Government; Colin McLaren, Drinking Water Quality Regulator for
Scotland; Randal Scott, Drinking Water Inspectorate for Northern Ireland; Rowena Tye,
Office of Water Services; Tony Smith, Chief Executive, Consumer Council for Water.
This letter is being sent electronically to Board Level and day-to-day contacts of water companies and stated contacts of lining manufacturers and contractors. Please acknowledge receipt by email to dwi.informationletters@defra.gsi.gov.uk. Hard copies are not being sent but the letter may be freely copied.
Yours faithfully
Prof. Jeni Colbourne MBE
Chief Inspector of Drinking Water
Appendix A (MS Word format)
Appendix B (MS Word format)
Appendix C (MS Word format)