Pipeline Condition Assessment. Condition Assessment Investment Strategy. What s going on down there? 5/16/2018 TRENCHLESS ASIA 2018

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1 wrc-infrastructure.co.uk TRENCHLESS ASIA 2018 Pipeline Condition Assessment Peter Henley WRc Infrastructure 7-8 May 2018 Organised by Event Partner Platinum Sponsors What s going on down there? Condition Assessment Investment Strategy High Resolution Capital Efficiency Capital Commitment Cost of Inspection Lower Resolution 1

2 External - NDT Inspection Traditional methods Exposing the pipe and measuring the remaining pipe wall thickness Typical techniques used are ultrasonicsand electro magnetics Limited to a snapshot of the pipe at that location Internal Pipeline Inspection Techniques Small and medium leaks are hard to find with external tools Inline technologies bring the sensor to the leak Both type of inspection can offer Pipe Wall Assessment (PWA) in live mains Tethered Free- Swimming wrcplc.co.uk 6 Tethered Inspection - Sahara Acoustic Leak Detection & CCTV Acoustic sensor hears leaks Other sensors can be added Detects 0.1 Ml/d per km wrcplc.co.uk 7 wrcplc.co.uk 8 2

3 5/16/2018 Free Swimming High Resolution Inspection Free Swimming Inspection Systems Pure SmartBall Aquam Bullet Systems such as Pure PipeDiver & Aquam Pipescan Provide high resolution data on pipe condition Detailed Pipeline Assessment Results wrcplc.co.uk 9 Condition Assessment Gravity Sewers CCTV Inspection CCTV Inspection - defect observation Well established technique for assessing the condition of sewer Depends on the skill of the surveyor for accuracy 3

4 5/16/2018 Typical Electro Scan Survey Plot Gravity Sewers - Electro Scan Identifies infiltration sources that CCTV doesn t see Quantifies the amount of infiltration Allowing rehabilitation to be better targeted Page 14 Case Study Southern Water Romsey Rising Main - SmartBall Survey Electro Scan & CCTV Comparisons B C 1. Provided operational confidence in the technology 2. Confirmed the outputs available from the technology 3. Understand the context in which the results would form part of the capital maintenance targeting process and decision tree - Capital Maintenance Efficiency Strategy A Joint Joint A B C wrcplc.co.uk 15 Page 15 4

5 Case Study Findings 2.4km Ductile Iron Wastewater Pressure Main No leaks presenting No stationary, trapped pockets of gas 3 vertical blanked Ts discovered during planning Condition Assessment Results Suggested Actions Leak location using in-pipe survey Leak type Suggested action Small leak, cast/spun iron joint Stable Monitor through regular data review Large leak, cast/spun iron joint Stable Plan in repair at time of lower reactive maintenance Leak on cast/spun iron pipe barrel Critical Urgent repair Small leak, ductile iron or steel Unstable Large leak, ductile iron or steel Unstable Urgent repair Frequent monitoring through data review. Consider regular in-pipe surveys Several pockets of entrained air Multiple leaks observed in single survey Mixed Planned regular in-pipe inspections; determine sections which may benefit from rehabilitation rather than repair No significant deviation between the recorded pipeline route and that detected using SmartBall Survey Decision Tree - Examples What do we need to know? How do you find that out? What did we find out? How much of a 15km pipeline needs replacement? The condition and location of a brick sewer before nearby construction project starts? Leak and wire break detection using untethered inspection device on 30" pipeline Laser/sonar profile and deep tracing Only one pipe length requiring intervention 0.04% oftotal length. Mapped position of localised damage to brickwork and informed construction company of exact route of 150m sewer Survey Decision Tree - Examples What do we need to know? Which damaged sewer pipes are causing a waste water pumping station to be overwhelmed? How to minimise excavation locating and repairing 10m deep suspected leak? How do you find that out? What did we find out? Electro Scan of 600m section 63 infiltrations but 80% of infiltration restricted to just 3 sections 3% Sahara deep location and acoustic detection 5 M/ldleak location pinpointed. How much of a 2.8km 800mm steel pipeline is corroded, and requires intervention? Is there a large diameter leak not picked up by correlation? Acoustic and pipe wall loss assessment tool required Acoustic leak detection 4 pipes with corrosion spots > 60% through wall corrosion. 2% Leak located What is the route cause of corrosion and high number of historic bursts, and likely locations requiring intervention? To what extent are dead zebra mussels affecting treatment works? Acoustic and conductivity survey on 300m 250mm main Sonar profile scan using Sahara Gas pockets identified and new gas relief valves installed as well as providing new information on the route and material of the main. The location and quantification of mussels enabled planned maintenance How much of a 10km 400mm rising main requires replacement? Are trunk mains leaking? Free rolling leak detection and magnetic data inspection on a CI and AC pipeline. Upstream loss analysis followed by targeted inpipe leak detection The line of the main and pipe materials were very different from GIS. A significant length of replacement was de-scoped as the pipe was found to be new. Real loss of 2MLD estimated from analysis.leak found and repaired. 2 MLD saved. Can we increase pressure on the pipeline? 6km Untethered acoustic survey The extent to which joints are leaking on a 1500mm PCCP pipeline? Untethered 6km acoustic survey Leaks found at one previous repair and 2 scour points, the rest of the pipeline has not leaked in 40 years so pressure was successfully increased. The survey was an extremely worthwhile exercise that has identified an unexpected leak. Critical trunk mains should be subject to such inspections routinely to reduce risk to supply and allow for the repair of pipes in a planned manner. John Slattery (Senior Executive Engineer) wrcplc.co.uk 19 5

6 wrc-infrastructure.co.uk Thank you for your attention See me on JBP Stand 119 for further information PETER HENLEY WRC INFRASTRUCTURE 6