Post on 06-Mar-2018
Planning for Large Scale Trunk Main OutagesDee 72” Large Diameter Trunk Main CleaningColin Rimmer
Copyright © United Utilities Water PLC 2014
Dee 72” Large Diameter Trunk Main Cleaning Presentation Content
1. United Utilities Trunk Main Cleaning Programme2. Dee 72” LDTM Cleaning Details / Scope3. Outage Planning4. Outage Preparation Work5. Bulk Supply Point Rezones & Full Isolation6. Cleaning method / Pre & Post survey camera footage 7. Invert flush / Recharge / Robust Flush8. Modelling Support Summary9. Questions
United Utilities eight year cleaning and maintenance programme between 2006 and 2014 targeted their largest and most important water mains and aqueducts.
Supplying drinking water to around seven million customers in North West England the programme aimed to clean and refurbish more than 619km of their large diameter trunk mains.
This level of cleaning programme had never been attempted before within the water industry.
1. United Utilities LDTM Cleaning Programme
The Dee Large Diameter Trunk Main is the main water supply pipeline for customers in Merseyside and parts of Cheshire. Pumped from Chester to Prescot the 65km pipeline has been in place since the 1960s. The Dee LDTM can supply up to 369 million litres a day to over 1.7 million customers.
Since the pipes were installed over 40 years ago deposits of iron and manganese which occur naturally in raw water from the upland reservoirs have built up on the insides of the pipes. Although not harmful to health these deposits can result in the discolouration of the drinking water. Therefore the scope was to remove theses deposits from the pipe walls to significantly reduce the discoloured water risk.
The Dee LDTM provides up to a fifth of the supply requirement for United Utilities therefore during the required outage there was heavy reliance on other key installations to ensure that the supply to customers was maintained.
Phase 1 started in June 2007Phase 2 started in April 2014
Phase 160” & 72” ST
Phase 2 72” ST
2. Dee 72” LDTM Cleaning Details / Scope
The Dee Large Diameter Trunk Main is the main water supply pipeline for customers in Merseyside and parts of Cheshire. Pumped from Chester to Prescot the 65km pipeline has been in place since the 1960s. The Dee LDTM can supply up to 369 million litres a day to over 1.7 million customers.
Since the pipes were installed over 40 years ago deposits of iron and manganese which occur naturally in raw water from the upland reservoirs have built up on the insides of the pipes. Although not harmful to health these deposits can result in the discolouration of the drinking water. Therefore the scope was to remove theses deposits from the pipe walls to significantly reduce the discoloured water risk.
The Dee LDTM provides up to a fifth of the supply requirement for United Utilities therefore during the required outage there was heavy reliance on other key installations to ensure that the supply to customers was maintained.
Phase 1 started in June 2007Phase 2 started in April 2014
Phase 160” & 72” ST
Phase 2 72” ST
2. Dee 72” LDTM Cleaning Details / Scope
Phase 272”
Phase 1 60” & 72”
Huntington WTW
Prescot SR
Outage Information
NORTON TOWER
PRESCOT WTW
DANS ROAD
CUERDLEY
JUBITS
CHAPEL LANE
RITHERUP
HOLT LANE
PORTICO
Warrington & South Widnes
South Liverpool
North Warrington & North Widnes
Rainhill
St Helens
Whiston
Utilise the adjacent 42” Vyrnwy Line 3
3. Outage Planning
Initial modelled scenarios allowed the key business stakeholders to plan and evaluate the requirements for the proposed outage.
• For example model results helped understand the impact the capacity reduction would have on the production figures at Huntington WTW.
3. Outage Planning
Initial modelled scenarios allowed the key business stakeholders to plan and evaluate the requirements for the proposed outage.
• For example model results helped understand the impact the capacity reduction would have on the production figures at Huntington WTW.
From On Average 260 Ml/d to 170 Ml/d
3. Outage Planning
Initial modelled scenarios allowed the key business stakeholders to plan and evaluate the requirements for the proposed outage.
• For example model results helped understand the impact the capacity reduction would have on the production figures at Huntington WTW.
From On Average 260 Ml/d to 170 Ml/d
North LiverpoolTrunk Mains
Outage Preparation ‐ Flushing the 42” Vyrnwy Extension (Cast Iron Section)
North LiverpoolTrunk Mains
Outage Preparation ‐ Flushing the 42” Vyrnwy Extension (Cast Iron Section)
North LiverpoolTrunk Mains
Outage Preparation ‐ Flushing the 42” Vyrnwy Extension (Cast Iron Section)
North LiverpoolTrunk Mains
Outage Preparation ‐ Flushing the 42” Vyrnwy Extension (Cast Iron Section)
North LiverpoolTrunk Mains
Outage Preparation ‐ Flushing the 42” Vyrnwy Extension (Cast Iron Section)
North LiverpoolTrunk Mains
Outage Preparation ‐ Flushing the 42” Vyrnwy Extension (Cast Iron Section)
North LiverpoolTrunk Mains
800mm Overland PipeFlush / Condition
Outage Preparation ‐ Flushing the 42” Vyrnwy Extension (Cast Iron Section)
North LiverpoolTrunk Mains
800mm Overland PipeFlush / Condition
Outage Preparation ‐ Flushing the 42” Vyrnwy Extension (Cast Iron Section)
North LiverpoolTrunk Mains
800mm Overland PipeFlush / Condition
Outage Preparation ‐ Flushing the 42” Vyrnwy Extension (Cast Iron Section)
The model predicts a maximum flushing flow rate of 77.10 Ml/d
Outage Preparation – PODDS Model Predictions (Flushing duration & Optimum Time)
The model predicts a maximum flushing flow rate of 77.10 Ml/d
PODDS models results show that the main needs to be flushed for 6 hours between 00:00 hours & 07:00 hours
Outage Preparation – PODDS Model Predictions (Flushing duration & Optimum Time)
NEEDLE VALVEDEE OUTAGE
DEE
WAT
ER DOWN VL3
42” CI M
AIN
North Liverpool Trunk MainNorth Liverpool Trunk Mains Reconfiguration
NEEDLE VALVEDEE OUTAGE
DEE
WAT
ER DOWN VL3
42” CI M
AIN
North Liverpool Trunk MainNorth Liverpool Trunk Mains Reconfiguration
HaweswaterAqueduct
WoodgateHill SR
NEEDLE VALVEDEE OUTAGE
DEE
WAT
ER DOWN VL3
42” CI M
AIN
North Liverpool Trunk MainNorth Liverpool Trunk Mains Reconfiguration
HaweswaterAqueduct
WoodgateHill SR
Southport DMZPumped from Bickerstaffe
St Helens NorthPumped fromKnowsley Dee Booster
Liverpool NorthSupplied directlyFrom the NTM’s
North Liverpool Trunk Mains Demand
Southport
Formby
Maghull
Aintree
Ormskirk
Skelmersdale
Kirkby
Bootle
Fazakerley
Croxteth
Walton St Helens
Prescot WTW
WELM Flow Control Valve Model Predictions and Testing
Modelling was required to understand how the flow control valve would react once active.There were concerns raised that the higher pressure on the WELM could cause a burst event downstream.
Testing confirmed that the control valve was able to supply 60% of the North Trunk Mains Demand.
WELM Flow Control Valve Model Predictions and Testing
Modelling was required to understand how the flow control valve would react once active.There were concerns raised that the higher pressure on the WELM could cause a burst event downstream.
Dial‐In pressure logger directly downstream of the FCV
Testing confirmed that the control valve was able to supply 60% of the North Trunk Mains Demand.
Start of test
To provide extra resilience for customers in St Helens during the outage of the Dee LDTM it was recommended that we utilise the capacity within an existing service reservoir.To maintain supply during a burst scenario water would be required to flow in the reverse direction which would possibly cause water discolouration from the 15” PV pipe.
Outage Preparation – Crank SR Flow Reversal / Flush
Crank SR Flow Reversal / Flush (cont)
PODDS modelling recommended that the main was flushed for a minimum of 3 hours
Portico Lane Isolation – Brownedge SR Inlet Mains Conditioning & Flushing
12.8 Ml/d
4.0 Ml/d
The average demand downstream of Brownedge SR is as follows;SR No1 (Pumped) = 3.3 Ml/dSR No2 (Gravity) = 11.7 Ml/d
5. Rezoning Bulk Supply Points onto Vyrnwy Line 3 / Isolation & ConditioningDay 1 – 00:00 to 24:00 Rezone and send Dee Water down VL3
Day 2 & 3 – 24:00 to 31:00 & 48:00 to 55:00 Flush the 42” Extension
Day 4 – 72:00 to 96:00 Rezone Chapel Lane, Ritherup & Holt Lane onto VL3
Day 5 – 96:00 to 120:00 Rezone Dans Road (Warrington & Widnes) onto VL3
Day 7 – 144:00 to 168:00 Rezone Jubits Lane onto VL3
Day 8 – 168:00 to 192:00 Isolate the 72” Dee Main
Day 9 to 12 – 192:00 to 288:00 utilise the WELM & the 42” extension then close Link Main
Day 6 – 120:00 to 144:00 Rezone Cuerdley onto VL3
Day 12 to 14 – 288:00 to 336:00 Open the final 500m & WELM into SR
5. Rezoning Bulk Supply Points onto Vyrnwy Line 3 / Isolation & ConditioningDay 1 – 00:00 to 24:00 Rezone and send Dee Water down VL3
Day 2 & 3 – 24:00 to 31:00 & 48:00 to 55:00 Flush the 42” Extension
Day 4 – 72:00 to 96:00 Rezone Chapel Lane, Ritherup & Holt Lane onto VL3
Day 5 – 96:00 to 120:00 Rezone Dans Road (Warrington & Widnes) onto VL3
Day 7 – 144:00 to 168:00 Rezone Jubits Lane onto VL3
Day 8 – 168:00 to 192:00 Isolate the 72” Dee Main
Day 9 to 12 – 192:00 to 288:00 utilise the WELM & the 42” extension then close Link Main
Day 6 – 120:00 to 144:00 Rezone Cuerdley onto VL3
Day 12 to 14 – 288:00 to 336:00 Open the final 500m & WELM into SR
5. Rezoning Bulk Supply Points onto Vyrnwy Line 3 / Isolation & ConditioningDay 1 – 00:00 to 24:00 Rezone and send Dee Water down VL3
Day 2 & 3 – 24:00 to 31:00 & 48:00 to 55:00 Flush the 42” Extension
Day 4 – 72:00 to 96:00 Rezone Chapel Lane, Ritherup & Holt Lane onto VL3
Day 5 – 96:00 to 120:00 Rezone Dans Road (Warrington & Widnes) onto VL3
Day 7 – 144:00 to 168:00 Rezone Jubits Lane onto VL3
Day 8 – 168:00 to 192:00 Isolate the 72” Dee Main
Day 9 to 12 – 192:00 to 288:00 utilise the WELM & the 42” extension then close Link Main
Day 6 – 120:00 to 144:00 Rezone Cuerdley onto VL3
Day 12 to 14 – 288:00 to 336:00 Open the final 500m & WELM into SR
5. Rezoning Bulk Supply Points onto Vyrnwy Line 3 / Isolation & ConditioningDay 1 – 00:00 to 24:00 Rezone and send Dee Water down VL3
Day 2 & 3 – 24:00 to 31:00 & 48:00 to 55:00 Flush the 42” Extension
Day 4 – 72:00 to 96:00 Rezone Chapel Lane, Ritherup & Holt Lane onto VL3
Day 5 – 96:00 to 120:00 Rezone Dans Road (Warrington & Widnes) onto VL3
Day 7 – 144:00 to 168:00 Rezone Jubits Lane onto VL3
Day 8 – 168:00 to 192:00 Isolate the 72” Dee Main
Day 9 to 12 – 192:00 to 288:00 utilise the WELM & the 42” extension then close Link Main
Day 6 – 120:00 to 144:00 Rezone Cuerdley onto VL3
Day 12 to 14 – 288:00 to 336:00 Open the final 500m & WELM into SR
5. Rezoning Bulk Supply Points onto Vyrnwy Line 3 / Isolation & ConditioningDay 1 – 00:00 to 24:00 Rezone and send Dee Water down VL3
Day 2 & 3 – 24:00 to 31:00 & 48:00 to 55:00 Flush the 42” Extension
Day 4 – 72:00 to 96:00 Rezone Chapel Lane, Ritherup & Holt Lane onto VL3
Day 5 – 96:00 to 120:00 Rezone Dans Road (Warrington & Widnes) onto VL3
Day 7 – 144:00 to 168:00 Rezone Jubits Lane onto VL3
Day 8 – 168:00 to 192:00 Isolate the 72” Dee Main
Day 9 to 12 – 192:00 to 288:00 utilise the WELM & the 42” extension then close Link Main
Day 6 – 120:00 to 144:00 Rezone Cuerdley onto VL3
Day 12 to 14 – 288:00 to 336:00 Open the final 500m & WELM into SR
5. Rezoning Bulk Supply Points onto Vyrnwy Line 3 / Isolation & ConditioningDay 1 – 00:00 to 24:00 Rezone and send Dee Water down VL3
Day 2 & 3 – 24:00 to 31:00 & 48:00 to 55:00 Flush the 42” Extension
Day 4 – 72:00 to 96:00 Rezone Chapel Lane, Ritherup & Holt Lane onto VL3
Day 5 – 96:00 to 120:00 Rezone Dans Road (Warrington & Widnes) onto VL3
Day 7 – 144:00 to 168:00 Rezone Jubits Lane onto VL3
Day 8 – 168:00 to 192:00 Isolate the 72” Dee Main
Day 9 to 12 – 192:00 to 288:00 utilise the WELM & the 42” extension then close Link Main
Day 6 – 120:00 to 144:00 Rezone Cuerdley onto VL3
Day 12 to 14 – 288:00 to 336:00 Open the final 500m & WELM into SR
5. Rezoning Bulk Supply Points onto Vyrnwy Line 3 / Isolation & ConditioningDay 1 – 00:00 to 24:00 Rezone and send Dee Water down VL3
Day 2 & 3 – 24:00 to 31:00 & 48:00 to 55:00 Flush the 42” Extension
Day 4 – 72:00 to 96:00 Rezone Chapel Lane, Ritherup & Holt Lane onto VL3
Day 5 – 96:00 to 120:00 Rezone Dans Road (Warrington & Widnes) onto VL3
Day 7 – 144:00 to 168:00 Rezone Jubits Lane onto VL3
Day 8 – 168:00 to 192:00 Isolate the 72” Dee Main
Day 9 to 12 – 192:00 to 288:00 utilise the WELM & the 42” extension then close Link Main
Day 6 – 120:00 to 144:00 Rezone Cuerdley onto VL3
Day 12 to 14 – 288:00 to 336:00 Open the final 500m & WELM into SR
5. Rezoning Bulk Supply Points onto Vyrnwy Line 3 / Isolation & ConditioningDay 1 – 00:00 to 24:00 Rezone and send Dee Water down VL3
Day 2 & 3 – 24:00 to 31:00 & 48:00 to 55:00 Flush the 42” Extension
Day 4 – 72:00 to 96:00 Rezone Chapel Lane, Ritherup & Holt Lane onto VL3
Day 5 – 96:00 to 120:00 Rezone Dans Road (Warrington & Widnes) onto VL3
Day 7 – 144:00 to 168:00 Rezone Jubits Lane onto VL3
Day 8 – 168:00 to 192:00 Isolate the 72” Dee Main
Day 9 to 12 – 192:00 to 288:00 utilise the WELM & the 42” extension then close Link Main
Day 6 – 120:00 to 144:00 Rezone Cuerdley onto VL3
Day 12 to 14 – 288:00 to 336:00 Open the final 500m & WELM into SR
5. Rezoning Bulk Supply Points onto Vyrnwy Line 3 / Isolation & ConditioningDay 1 – 00:00 to 24:00 Rezone and send Dee Water down VL3
Day 2 & 3 – 24:00 to 31:00 & 48:00 to 55:00 Flush the 42” Extension
Day 4 – 72:00 to 96:00 Rezone Chapel Lane, Ritherup & Holt Lane onto VL3
Day 5 – 96:00 to 120:00 Rezone Dans Road (Warrington & Widnes) onto VL3
Day 7 – 144:00 to 168:00 Rezone Jubits Lane onto VL3
Day 8 – 168:00 to 192:00 Isolate the 72” Dee Main
Day 9 to 12 – 192:00 to 288:00 utilise the WELM & the 42” extension then close Link Main
Day 6 – 120:00 to 144:00 Rezone Cuerdley onto VL3
Day 12 to 14 – 288:00 to 336:00 Open the final 500m & WELM into SR
WELM
5. Rezoning Bulk Supply Points onto Vyrnwy Line 3 / Isolation & ConditioningDay 1 – 00:00 to 24:00 Rezone and send Dee Water down VL3
Day 2 & 3 – 24:00 to 31:00 & 48:00 to 55:00 Flush the 42” Extension
Day 4 – 72:00 to 96:00 Rezone Chapel Lane, Ritherup & Holt Lane onto VL3
Day 5 – 96:00 to 120:00 Rezone Dans Road (Warrington & Widnes) onto VL3
Day 7 – 144:00 to 168:00 Rezone Jubits Lane onto VL3
Day 8 – 168:00 to 192:00 Isolate the 72” Dee Main
Day 9 to 12 – 192:00 to 288:00 utilise the WELM & the 42” extension then close Link Main
Day 6 – 120:00 to 144:00 Rezone Cuerdley onto VL3
Day 12 to 14 – 288:00 to 336:00 Open the final 500m & WELM into SR
WELM
5. Rezoning Bulk Supply Points onto Vyrnwy Line 3 / Isolation & ConditioningDay 1 – 00:00 to 24:00 Rezone and send Dee Water down VL3
Day 2 & 3 – 24:00 to 31:00 & 48:00 to 55:00 Flush the 42” Extension
Day 4 – 72:00 to 96:00 Rezone Chapel Lane, Ritherup & Holt Lane onto VL3
Day 5 – 96:00 to 120:00 Rezone Dans Road (Warrington & Widnes) onto VL3
Day 7 – 144:00 to 168:00 Rezone Jubits Lane onto VL3
Day 8 – 168:00 to 192:00 Isolate the 72” Dee Main
Day 9 to 12 – 192:00 to 288:00 utilise the WELM & the 42” extension then close Link Main
Day 6 – 120:00 to 144:00 Rezone Cuerdley onto VL3
Day 12 to 14 – 288:00 to 336:00 Open the final 500m & WELM into SR
WELM
5. Rezoning Bulk Supply Points onto Vyrnwy Line 3 / Isolation & ConditioningDay 1 – 00:00 to 24:00 Rezone and send Dee Water down VL3
Day 2 & 3 – 24:00 to 31:00 & 48:00 to 55:00 Flush the 42” Extension
Day 4 – 72:00 to 96:00 Rezone Chapel Lane, Ritherup & Holt Lane onto VL3
Day 5 – 96:00 to 120:00 Rezone Dans Road (Warrington & Widnes) onto VL3
Day 7 – 144:00 to 168:00 Rezone Jubits Lane onto VL3
Day 8 – 168:00 to 192:00 Isolate the 72” Dee Main
Day 9 to 12 – 192:00 to 288:00 utilise the WELM & the 42” extension then close Link Main
Day 6 – 120:00 to 144:00 Rezone Cuerdley onto VL3
Day 12 to 14 – 288:00 to 336:00 Open the final 500m & WELM into SR
WELM
Invert Flush Norton Tower to South Bank (River Mersey & Manchester Ship Canal Crossing)
7. Invert flush / Recharge / Robust Flush
Invert Flush Norton Tower to South Bank (River Mersey & Manchester Ship Canal Crossing)
Rainhill
7. Invert flush / Recharge / Robust Flush
Invert Flush Norton Tower to South Bank (River Mersey & Manchester Ship Canal Crossing)
Rainhill
7. Invert flush / Recharge / Robust Flush
Invert Flush Rainhill to South Bank (River Mersey & Manchester Ship Canal Crossing)
Recharge the 72” between Norton & the Cricket Ground using the bypass valves at Norton Tower
Invert flush / Recharge / Robust Flush
Recharge the 72” between Norton & the Cricket Ground using the bypass valves at Norton Tower
Invert flush / Recharge / Robust Flush
Recharge the 72” between Norton & the Cricket Ground using the bypass valves at Norton Tower
Invert flush / Recharge / Robust Flush
Recharge the 72” between Norton & the Cricket Ground using the bypass valves at Norton Tower
Invert flush / Recharge / Robust Flush
Control the opening of the Cuerdley valve to manage the flush into Open Reservoir No4;
Invert flush / Recharge / Robust Flush
Control the opening of the Cuerdley valve to manage the flush into Open Reservoir No4;
Invert flush / Recharge / Robust Flush
Control the opening of the Cuerdley valve to manage the flush into Open Reservoir No4;
Invert flush / Recharge / Robust Flush
Control the opening of the Cuerdley valve to manage the flush into Open Reservoir No4;
Invert flush / Recharge / Robust Flush
Daily conference calls
8. Modelling Support SummaryClean water modelling proved key and vital to the success of the overall project. Initial modelled scenarios allowed the key business stakeholders to plan and evaluate the requirements for the proposed outage. This continued during the outage period as data from solution models was able to guide the whole project team on a day to day basis, this ensured that the required network changes were completed without causing any customer complaints.
Based on the knowledge gained it is evident that clean water modelling is a crucial tool for future schemes.