DISTRIBUTION, OPERATION and MAINTENANCE STRATEGY ASSET MANAGEMENT WORK INSTRUCTION ISOLATION OF A TREATED WATER STORAGE POINT ON THE WATER NETWORK

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1 ISOLATION OF A TREATED WATER STORAGE POINT ON Document Title: Document Reference: Work Instruction Isolation of a Treated Water Storage Point on the Water Network DOM-WN-WIN Approved By: Asset Management Title: General Manager

2 Record of Changes and Amendments Amendment No. 1 Section 3 Document Section/ Reference Number Document / Section Title DOMS Guidelines Training Version Number Amendment Date Archived Document / Section Text Affected A Oct 2013 Section added with text in page 4 Archived Document / Section Replaced By Sheet i

3 FOREWORD Background DOMS stands for Distribution Operation & Maintenance Strategy and is being used by Scottish Water to: Safeguard the quality of water to customers. Ensure that Scottish Water apply due diligence to their Scottish Water distribution network. The DOMS procedures and work instructions affect all functional staff who work on the network, which includes internal employees and employees of external organisations (i.e. planners, operators, delivery teams, Framework Contractors, or any other contractors). Through the application of the DOMS principles in day-to-day network activities, Scottish Water and their approved contractors will operate and maintain their water distribution networks through operational best practice. This will allow Scottish Water to meet the following objectives: To maintain water quality; To maintain continuity of supply; To maintain water supply hygiene; To undertake water quality incident management; To maintain a cost-effective water supply; To ensure a course of action for timely network intervention (Capex and/or Opex); To maintain statutory obligations and customer satisfaction. Responsibility The responsibility for adoption and implementation of all DOMS procedures and work instructions rest with Scottish Water General Managers and senior managers of external organisations. It is the responsibility of all Scottish Water employees and those of external organisations to comply with DOMS procedures and work instructions. Document Control This document is a CONTROLLED DOCUMENT when viewed on Wavelength. The document becomes UNCONTROLLED if printed or downloaded from Wavelength or any other source. Refer to the Wavelength site for the latest version of this document. Change Request A change to this document can be requested by completing a Change Request Form - refer to document DISTRIBUTION OPERATION and MAINTENANCE STRATEGY GOVERNANCE (DOM- WN-GOV ) for change request procedure. Copyright Copyright of this document is owned by Scottish Water. The document may not be copied or reproduced in any way. Page i

4 CONTENTS FOREWORD... i CONTENTS...ii 1 PREAMBLE Instruction Objectives Related Parent Documents Related External Documents Related Internal Documents 1 2 PLANNING CHECKLIST DESCRIPTION. 2 4 APPENDIX A - TREATED WATER STORAGE POINT - IMPACT RISK ASSESSMENT SHEET.. 7 Page ii

5 1. PREAMBLE 1.1 Instruction Objectives This work instruction details the process for isolating a Treated Water Storage Point on the water network for cleaning or inspection purposes. 1.2 Related Parent Documents (DOM-WN-PRC ) Work Procedure Inspection of Treated Water Storage Points (DOM-WN-PRC ) Work Procedure Assessment of Treated Water Storage Points (DOM-WN-PRC ) Work Procedure Cleaning of Treated Water Storage Points 1.3 Related External Controlled Documents None 1.4 Related Internal Controlled Documents Scottish Water Hygiene Code of Practice (HCOP). DOM-WN-TBT DOMS Impact Assessment Form & Guide for Completion for Access too working on the SW Water Network DOM-WR-FOR Impact Assessment Form DOM-WN-PRC General Requirements For Hygiene DOM-WN-TBT SW DOMS TBT No 13 Protection of Controlled Waters DOM-WN-TBT SW DOMS TBT No 2 Boundary Valve Management 2. PLANNING CHECKLIST Refer to Impact Risk Assessment Sheet (Appendix A) for isolation of a treated water storage point. Main issues are listed below. Complete health and safety risk assessment and a DOMS Impact assessment form including: Valve Turning operations. Confined spaces Entry (if applicable). Any DOMS IAF completed must Now also be Risk Assessed For Maintaining Supplies to include any alternative supplies overland requirements, or tankering operations etc to mitigate any risk to both Water Quality and prevent any unnecessary Interruptions To Supply which will or may affect SW OPA Score. All Authorised DOMS IAF are now required to be sent to the Operation Log for Situational awareness with a Proposed or Planned start date. Water quality impact issues: Creating an interruption to supply. Closing a valve quickly and causing a burst. Change of flow pattern causing discolouration. Flooded air valves. Page 1 of 11

6 Impact risk assessment Risk assessment and Isolation method statement produced and approved. Utilisation of recently calibrated network model (if available). Impact on surrounding network - reduced or increased pressures? Discharge of chlorinated water. Isolation of TWSP will affect regulatory sampling programme who needs to be informed? Consider TWSP refilling timescale and methods WTW capacity to deliver TWSP refill volume should be reviewed. Risk mitigation/contingency plan: Identification of alternative feed (where appropriate). Temporary supplies. Sensitive and key account customer issues: Risk assessment to identify. Liaison Key account managers. Dialysis patients. Communication plans: Notify ICC ( Update with any Alarm / Telemetry affected etc while out of commission) Notify Sampling Section/Drinking Water Quality Section of proposed isolation of TWSP indicate proposed duration of isolation. Notify Water Treatment and Production to confirm duration of isolation and agree refilling timescale and methods. Update Ops Log. Notify affected customers. 3. DESCRIPTION Condition of Site Access IMPORTANT CHANGES TO THE HYGIENE CODE OF PRACTICE & DOMS PROCEDURES RESTRICTED ACCESS AREA DEFINITION. After the 1 st April 2008 the following access categories will apply: Restricted Areas - are those where direct contact may be made with partially or fully treated water within water treatment works or with treated water at any stage of its distribution to the point where it is made available to customers and areas where there is no direct contact with water but where a high degree of hygiene is still required. Examples of Restricted Areas are: Filter tanks Contact tanks Service reservoirs Pumping stations when any surfaces normally in contact with treated water are exposed Surge vessels Tanks associated with waterworks sludge treatment where water is re-cycled to the works Page 2 of 11

7 Excavations where the internal surfaces of existing mains/services (and new mains tie-ins) are exposed to atmosphere and/or there is any possibility of a contaminant entering the system. Any other area where treated or partially treated water is exposed to the atmosphere Boreholes Areas where there is no direct contact with water but where a high degree of hygiene is still required e.g. filter walkways around tanks, valve galleries and chemical treatment plants. For short term, occasional visits by external agencies (telephone companies, non-intrusive surveys by SWS staff etc) Access Certificates, including an associated job specific risk assessment, carried out by the nominated Responsible Person, must be issued for every job. All access by external agencies should be subject to Scottish Waters Security Policy. Any person working on hatches, cabling or instrumentation associated with Restricted Areas must be subject to Access Certificates, risk assessed by the nominated Scottish Water Responsible Person and ideally supervised whilst the work is being carried out. Where these jobs have the potential or actual contact with treated or partially treated water, then the person/s working on the job must hold the appropriate Authorisation Card and have had DOMS / HCoP training. Non - Restricted Areas - are those areas where no direct contact may be made with partially or fully treated water, e.g. control panels within pumping stations, the grounds, offices, and toilet facilities at water installations, etc. It is not a requirement to have an Authorisation Card or DOMS / HCoP training to access these areas. Visitors, who are not expected to carry out work that could potentially affect the quality of the water supply, are permitted access to Restricted and None Restricted Areas provided that: (a) They are properly supervised by a competent Scottish Water employee (b) Arrangements are implemented to ensure that the recommendations of the Hygiene Code of Practice are not compromised; including a risk assessment of any proposed activity is carried out by the nominated Responsible Person. If there is a need for further information or assistance with interpretation of Restricted Area Access, contact the relevant operational area Public Health Team who will provide further guidance. If guidance is required outside of office hours the Public Health Team are on call 24 hours / 7 days a week and contact details are available though the Operational Management Centre and / or the Corporate Satellite System Standby Log. All employees, contractors and consultants, etc, working for or on behalf of Scottish Water will be required to complete formal training in water supply hygiene practices and also in Scottish Water's Distribution Operations Maintenance Strategy (DOMS). Scottish Water will make training modules available to support this process and employees, contractors and consultants must complete this training in the relevant category of DOMS with a training provider that has been approved to deliver this training on behalf of Scottish Water. This training will be formally recorded and registered with Energy & Utility Skills (EU Skills) as part of the Water Industry Registration Scheme (WIRS) and an authorisation card will be issued by EU Skills on behalf of Scottish Water for both water hygiene and Scottish Water DOMS procedures. Note: EUS Skills hygiene training will be equivalent to module 1 of SW DOMS. The team members must all have a valid Hygiene Authorisation and DOMS card with the relevant DOMS modules completed for this work activity on site and must comply with: Page 3 of 11

8 DOMS TRAINING GUIDELINES EVIDENCE OF DOMS TRAINING In 2007, Scottish Water set the goal that all staff working on the water network receives the relevant DOMS training by the end of the year. The result - over 9,000 people have currently completed DOMS training to support their network activities since it has been introduced within SW. All staff, both internal and external, who work on the water network, MUST complete the relevant Distribution, Operation and Maintenance Strategy (DOMS) training associated with their specific network activities and as a result MUST carry two cards which confirm their training. DOMS training is available through a number of approved Training Providers and the registration of the training units taken by individuals is administered through EU Skills. The first card relates to training given around the Hygiene Code of Practice (HCoP) and the card usually coloured light blue, confirms the cardholder has completed this element, which includes a health screening questionnaire. The second card, usually coloured white, relates to training given around DOMS and the training units shown on the back of the card detail the type of DOMS related site activities that the cardholder can undertake. Both cards detail the name of the cardholder, along with their picture, which will allow confirmation that the cardholder is the person holding the card. Scottish Water staff may and will challenge all internal and external staff working on the water network at anytime to produce both their cards to ensure that cardholder has the relevant training and understanding of DOMS Procedures and Work Instruction for the specific task that they are undertaking. The following guidelines should be followed for deciding the course of action to take when either internal of external staff were found to be working on the water network, or any infrastructure that will be connected to our network, without the requisite HCoP/DOMS cards confirming training. 1) New starts - expectation that they will have their necessary HCoP/DOMS training organised by their employer within the first 4 weeks of them joining their company. They will not be allowed to work on the water network without the HCoP/DOMS training, even though they are being supervised by a person who has gone through the training. There is a minimal health risk here, which the health questionnaire, completed during the HCoP training, will confirm as acceptable or unacceptable. 2) Completed HCoP/DOMS Training but no card issued by EU Skills - staff in this situation can work on the water network as long as they can demonstrate that they have a 'cover note' issued by training providers. If a 'cover note' is produced, then the person challenging can ensure that 'cover note' refers to the actual person by checking the EU Skills web site against name or reference number. This will be done in conjunction with the relevant DOMS Working Group representative. 3) Person challenged on site and person has no HCoP/DOMS relevant training - if this scenario occurs then the person who has made the challenge will remove the person from working on the water network and contact the relevant business unit DOMS Working Group representative as the first point of contact. Together, the site contact and the DOMS Working Group representative will make the decision on whether work can or cannot continue after discussions with the employee s relevant organisation. Page 4 of 11

9 4) Person challenged on site and cannot produce HCoP/DOMS relevant training cards, but claims to have undergone training - if no cards can be produced, then the person challenging can not confirm that the person has had the relevant training by checking the EU Skills web site against name or reference number. This will be done in conjunction with the relevant DOMS Working Group representative. 5) Person challenged on site; DOMS CARD EXPIRED. If a DOMS card has expired and the person is waiting to attend a SW DOMS training course, a signed and dated cover note, with the course reference confirmation number and Registration Status clearly shown, must be issued by the person s line manager, in order to allow access to the network. The person must present this cover note on site. (Failure to provide cover note will result in the individual being removed from working on the network until a cover note is issued, or the individual is retrained and re-registered with EUSR) The cover note will only be valid for 3 months after the original card expiry date. After 3 months has elapsed, if the person has not re-registered and is NOT in possession of a new card or a cover note stating the person is awaiting delivery of a new card, then access to work on the network will be refused. All internal and external staff working on the water network must have completed the relevant training. If the site challenges are made by SW staff (and on occasions the DWQR) for all those working on the network, the message will be sent clearly that 'IF YOU HAVEN T HAD THE TRAINING YOU CANNOT WORK ON OUR NETWORK OR ANY INFRASTRUCTURE THAT WILL BE CONNECTED TO OUR NETWORK. While we all want to be balanced and professional in our company approach to this matter, water quality and customer satisfaction in our product is our paramount concern. Finally, can all Scottish Water staff note that for out-of-hours advice on public health issues, a representative from the Public Health Team can be contacted 24/7 through the ICC. Isolating a Treated Water Storage Point (see Appendix A) Complete a DOMS impact risk assessment form, which must consider the following: Any DOMS IAF completed must Now also be Risk Assessed For Maintaining Supplies to include any alternative supplies overland requirements, or tankering operations etc to mitigate any risk to both Water Quality and prevent any unnecessary Interruptions To Supply which will or may affect SW OPA Score. All Authorised DOMS IAF are now required to be sent to the Operation Log for Situational awareness with a Proposed or Planned start date. Isolation method statement single or twin compartments? Utilisation of recently calibrated network model (where one exists) Boundary valves / Strategic Valves If any of the isolating valves are boundary valves the boundary valve procedure must be followed with the valve operator contacting Control 24 Hour Telephone Number and advise of BV s Current status change If any of the isolating valves are temporarily open boundary valves or valves, which will affect a large area or population, then these valves must be operated by a Customer Operations Network Services Operator. Refer To DOMS DOM-WN-TBT SW DOMS TBT No 2 - Boundary Valves Management Water quality effects Operation of PRV on by-pass (if applicable) Customers affected - Key, sensitive, general Page 5 of 11

10 Internal customers Sampling Section, Water Production and Treatment ICC Information Control Centre Security: Whilst compartment(s) is out of service, all security measures are to be in place; security covers, vents, kiosks to be correctly secured; alarm system (where installed) to be set (armed when works have been completed daily or at end of task). Any temporary alternative supply arrangements Pressure changes in adjacent areas Identify potential areas of contamination risk - air valves, farm troughs, etc. Safe method of discharging chlorinated water * Refer To DOMS TBT DOM-WN-TBT SW DOMS TBT No 13 Protection of Controlled Waters * Scour valves - availability, condition and discharge points. * Fire Hydrants - availability, condition and discharge area. If refilling TWSP - obtain agreement with Water Treatment and Production Section to agree refilling timescale and methods Obtain approval to proceed. Complete health and safety risk assessment. Notify internal and external customers identified in communication plan. Check fittings on-site, which will affect process, isolating valves, PRVs, scour valves and fire hydrants. Complete customer notification - customers may require to be notified of isolation of TWSP, where the quality or pressure of their supply will be noticeably altered. Update Ops Log. Establish any temporary supplies required e.g. sensitive or Key Customers. Page 6 of 11

11 APPENDIX A DOMS O&M INTERVENTIONS TREATED WATER STORAGE POINT - IMPACT RISK ASSESSMENT SHEET 1. PROPOSED WORK DETAILS Ellipse TWSP Name: Ellipse Asset No: Details of work: WAMS Ref. No: Location Details: WOA Name: NGR: WSZ Name: 2. METHOD STATEMENT An isolation method statement should be completed for each TWSP, before and work is undertaken on site. The following checklist should be considered (not exhaustive) and the method statement must be made known to all stakeholders involved or affected by the proposed works or shutdown: Considered action Comments Prepare site plan which details each TWSP valve, PRV, hydrant and the pipework layout Confirm if TWSP is single or twin compartment full or mid height wall? Detail isolation of all TWSP compartments and introducing alternative supplies Detail location of bypass does by-pass include PRV? If no PRV how can potential pressure problems be controlled and reduced? Identify alternative supply to area affected Issue isolation method statement to all operational/stakeholders affected by proposed works Consider TWSP refilling timescale and methods WTW capacity to deliver TWSP refill volume should be reviewed Page 7 of 11

12 3. RISK ASSESSMENT The Risk Assessment is a desktop exercise based on the history of the area and the experience of local customer operations staff. It should identify and address known and foreseeable problems specific to the local area network, which will be affected by the isolation of the TWSP from the water network. The completion of the Risk Assessment does not negate the obligation of Customer Operations or contractors to exercise due diligence and ensure DOMS compliance at all times. Also log and make an appropriate response to any additional risks and impact identified during the course of the work (Refer to section 5) 4. GENERAL RISKS Is there a risk of disruption to supply? Risk (trunk or pumping mains, supply pipes etc): Impact: Proposed mitigation action: Is there a risk of causing discoloured water? Risk (valve ops, flow reversals, mixing etc): Impact: Proposed mitigation action: Are any properties on Low Pressure Register who may be affected? Location No. of Props On LOS Register (/at risk) Page 8 of 11

13 Is there a risk of poor pressure problems? Risk (valve ops etc): Impact: Proposed mitigation action: Is there a risk of contamination? Risk (amber, red no. of customers potentially Impact: affected, etc): Proposed mitigation action: Does the area contain any Key Customers? Name Address Type (i.e. 24 hr user etc) Is there a risk to Key Customers? Nature of Risk: Impact: Proposed mitigation action: Does the area contain any Sensitive Customers? Name Address Why sensitive Page 9 of 11

14 Is there a risk to Sensitive Customers? Nature of Risk: Impact: Proposed mitigation action: Any other foreseeable risks? Describe risk: Impact: Proposed mitigation action: 4. COMMUNICATION PLAN Before work on site starts Signed Date Liaison Requirements Completed Contact Centre notified Customer Operations Team notified SW Scientific Services (Lab) sampling section SW Water Production Team notified SW Security notified After work on site completed* Signed Date Works area Left Safe Restoration works complete Call Centre Notified SW Security notified Team Manager Notified Data Capture Complete * Checklist to be completed by SW Staff supervisory staff Page 10 of 11

15 5. ADDITIONAL RISK AND IMPACT LOG Risks not accounted for but identified during work operation and consequential impact: Site Works Supervisor: Name: Signed:. Date: Page 11 of 11