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SAN DIEGO COUNTY WATER AUTHORITY PIPELINE RELINING PROGRAM Keeping the Water Flowing. Panel Members. Misha Troyan , P.E., EPC Consultants Mike Kenny , SDCWA Jose Martinez , R.W. Beck. Bio – Misha Troyan, P.E. San Diego Area Manager, EPC Consultants
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SAN DIEGO COUNTY WATER AUTHORITY PIPELINE RELINING PROGRAM Keeping the Water Flowing
Panel Members • Misha Troyan, P.E., EPC Consultants • Mike Kenny, SDCWA • Jose Martinez, R.W. Beck
Bio – Misha Troyan, P.E. • San Diego Area Manager, EPC Consultants • B.S. Civil Engineering, University of California at Berkeley • Construction Manager for 27,000 feet of pipeline relining projects • EPC has been a prime or subconsultant on four reline projects to date
Bio – Mike Kenny • Senior Construction Manager, SDCWA • Oversight on $130 million in current construction projects • B.S. Construction Management, Colorado State University • 18 years with SDCWA including Inspection Manager of Construction Inspection Group • Member, CMAA Board of Directors, San Diego Chapter
Bio – Jose Martinez • Construction Manager, R.W. Beck • B.S. Mechanical Engineering, United States Naval Academy • Certified Naval Nuclear Engineer by the Department of Energy • Construction Manager on recent design-build & urgent pipeline relines
Presentation Goal • Who is the San Diego County Water Authority? • What is PCCP? • Why is the Water Authority relining its pipelines? • How does relining work? • When did relining work start and what is the future of the program?
Regional Background • More than 200 years of water development • Major focus of dam construction at end of 19th century • SDCWA organized in 1944 to meet area's wartime mission • Fifth of five major pipelines completed in 1982 Mission Dam was constructed by Spanish settlers in 1769.
SDCWA Regional Role • Water wholesaler provides 90% of San Diego County’s water • 24 member agencies serving a population of 3.7 million people Completed in 2003, Olivenhain Dam is the largest RCC dam in the world • Active in state and federal government as advocate for regional water supply
Infrastructure Overview • Key Components • 300 miles of pipe • 82.5 miles of PCCP (gravity) • 48 to 108 inch • Expanding treated water capability
Historical Failures • February 1979 – 66” (1959) • December 1980 – 66” (1959) • May 1982 – 66” (1959) • October 1990 – 84” (1972) • November 1993 – 96” (1972)* • May 2006 – 66” (1959) * • October 2008 – 72” (1976)* * High pressure section
Aqueduct Protection Program (APP) • Established by SDCWA Board in 1991 in response to failures and concern about pipeline condition • Risk Management role • May 2006 Failure = $6 million • Feb 2008 Replacement = $1 million • May 2008 Carbon Fiber Urgent Repair = $530k • $41 million over the next 30 years; 4 regular staff plus support staff (as of 2003)
APP – What Does it Do? • Monitors and mitigates corrosion related damage • Identifies pipeline nearing end of service life and schedules rehabilitation/replacement • Documentation • Determines remaining service life and pipeline decay index (PDI) for analysis
Condition Assessment Tools • In Service • Failures • Acoustical Monitoring • Out of Service • Visual/Sounding • Remote Field Eddy Current • Impact Echo (limited effectiveness)
Acoustic Fiber Optics (AFO) • Real-time monitoring of prestressing wires • Hydrophone Arrays • Acoustic Fiber Optic Cable • Authority Pipelines Currently Being Monitored • Pipeline 3 = 19,715 feet • Pipeline 4 = 20,167 feet • Pipeline 5 = 65,000 feet • Crossover Pipeline = 39,600 feet
Visual Inspection Deformed Cylinder Thin Mortar Lining Cracked and Exposed Steel Cylinder
Sounding • Examination of External PCCP Wires • Sounding and removal of delaminated mortar coating • Cleaning and inspection of pre-stressed wires
Remote Field Eddy Current • 30 broken wires estimated • 27 broken wires found
Condition Assessment • Pipeline Decay Index (PDI) • Summary of all factors • Determines remaining service life • Determines maintenance schedule • Regular data reviews and updates • Potential impacts via GIS maps • Watercourse, schools, homes, roads, commercial zones, etc.
Lessons Learned • In-Plant inspection is key • Proper coating and lining • Steel can condition • Consider bedding and environment • San Diego has very corrosive soils high in chlorides • Rock backfilled against pipe cracks coating • Poor diapers at joints on older PCCP • Effect of shutdowns on PCCP
Relining Considerations • Costs: • Average reline cost = $1,300/ft • New Steel Pipe = $1,462/ft (rural) & $2,055/ft (urban) • Carbon fiber repair = $7,500/ft • Time: • Reduced OOS duration • 24-hour work • Community impacts: • Out of sight, out of mind • Environmental: • Minimizes dust, noise and impacts to habitat
Relining Background • New steel pipeline within PCCP • Process developed in early 1980s by SDCWA Assistant Chief Engineer, Buckley L. Ogden • Ogden’s pipe carrier • Process used around the nation and at the Water Authority today
Basic Relining Process • Portal Development • Liner installation & Welding • Grouting • Cement Mortar Lining • Closure Pieces • Portal Restoration
Emergency Repairs • Emergency vs. Urgent Repairs • Same Process, Compressed Timeline • Additional Variables • Communication
Reline Program Status • Total Budget: $787 million • Spent to date: $100 million • May 2006 Failure, $6 million • AFO repairs • Feb 2008 replacement, $1 million • May 2008 carbon fiber, $530k
Anything Else? Questions & Answers