The lining process that Black & Veatch used involved an initial tack coat of epoxy being applied to the host pipe, which improves the bond with the FRP lining."Major excavation of the carriageway was not allowed and replacement was not possible," said Man. "As conventional rehabilitation techniques such as slip lining were also not feasible, we had to use innovative in-situ methods within the pipe to get the job done."
Black & Veatch adopted the use of hand-applied fiber-reinforced plastic (FRP) for the rehabilitation of the mains. Various trials and demonstrations on the FRP system were carried out on site. Relining of the first main was completed by mid-December 2008 at an average rate of approximately 25-40 meters per day. Final inspections and pressure tests were completed and the first water main was re-commissioned in March 2009.
Work has now commenced on two other mains with all five mains targeted to be completed in early 2011.
"The Lion Rock Tunnel water mains are an essential component of Hong Kong's water supply network," said Man. "By using innovative technology, we are able to successfully rehabilitate these mains with minimal disruption to commuters who rely on the use of the tunnel every day."
Hong Kong's Water Supplies Department launched the Replacement and Rehabilitation Programme of Water Mains, one of the largest pipeline rehabilitation programs in the world, in 2000. The program aims to rehabilitate or replace a total of 3,000km of water mains by 2015, at an estimated cost of HK$ 19.2 billion (US$ 2.5 billion), improving the condition and reliability of Hong Kong's water supply network.
Black & Veatch is responsible for replacing or rehabilitating approximately one-third of the pipelines in the overall program, and is involved in Stages 1, 2 and 4.
About Black & Veatch
Black & Veatch is a leading global engineering, consulting and construction company specializing in infrastructure development in energy, water, telecommunications, management consulting, federal and environmental markets. Founded in 1915, Black & Veatch develops tailored infrastructure solutions that meet clients' needs and provide sustainable benefits. Solutions are provided from the broad line of service expertise available within Black & Veatch, including conceptual and preliminary engineering services, engineering design, procurement, construction, financial management, asset management, program management, construction management, environmental, security design and consulting, management consulting and infrastructure planning. With US$3.2 billion in revenue, the employee-owned company has more than 100 offices worldwide and has completed projects in more than 100 countries on six continents.
Black & Veatch's global water business provides innovative, technology-based solutions to utilities, governments and industries worldwide. Local project teams work with multinational water and wastewater treatment process experts to address site-specific challenges through a broad range of consulting, study, planning, design, design-build and construction management services. The company's Web site address is www.bv.com.
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