After much analysis and debate, a panel of industry veterans has selected the winners of ENR’s 7th annual Global Best Projects competition. Like ENR’s successful regional and national U.S. competitions, Global Best Projects identifies and honors the project teams behind outstanding design and construction efforts of the past year.
San Diego County Water Authority crews successfully completed the first of three coordinated shutdowns of the First Aqueduct in early March to launch a major renovation of dozens of structures on two pipelines, including the historic Pipeline 1 that first delivered imported water to the region in 1947.
The series of shutdowns was carefully planned for nearly four years to minimize impacts on the community and retail water agencies during retrofits of Pipelines 1 and 2, which comprise the First Aqueduct.
“The First Aqueduct has been a very reliable source of imported water for more than 70 years,” said Chris Castaing, operations and maintenance manager at the Water Authority. “These critical upgrades will make sure we can operate and maintain the pipelines for another several decades to transport water to the region for future generations.”
Started during the Water Authority’s 75th anniversary year, the $30 million First Aqueduct structure and lining renovation project is among the most complicated pipeline retrofits in agency history.
During the next two years, upgrades include replacing the lining on the steel pipe sections; removing 19 associated structures; and retrofitting 41 structures – all without jeopardizing water service to the region.
Crews complete work on and seal the top of a bifurcation structure. Photo: Water Authority
Pipeline structures that will be rehabilitated include valves, blowoffs, pump wells and access ways.
Approximately 4 miles of failing pipeline lining on the steel pipe sections will be carefully removed and replaced with new cement mortar lining. Cement mortar is the preferred material, because it protects the interior of the steel pipe from corrosion and premature failure, has a longer life, and is easier to maintain. The project also will add redundant connections to six flow control facilities between the two pipelines, greatly improving the aqueduct’s operational flexibility.
During the first shutdown between February 24 and March 5, crews isolated sections of the pipeline and took them out of service so work can be safely performed on those sections throughout the year. In late 2019, a second 10-day shutdown will allow crews to switch flows to the upgraded sections of pipe and isolate other sections for repairs.
In addition to completing the First Aqueduct structure and lining renovation project, the Water Authority also will perform assessments of 27 miles of the pipeline to determine if additional upgrades will be needed.
San Diego, Calif. – Welcome to the future.
That’s the message from the San Diego County Water Authority, which is developing and deploying cutting-edge techniques to maintain its 310 miles of giant pipes that provide water for 3.3 million residents across the region.
“This is all about assessing the condition of our pipelines through the most advanced technology at our disposal and performing repairs before age-related defects become an unforeseen issue,” said Martin Coghill, a senior water resources specialist for the Water Authority.
Coghill spoke before dozens of water industry officials and residents on hand for a Condition Assessment Technology Showcase during the Water Authority Board of Directors’ Engineering and Operations Committee in late August. The showcase included a review of the latest technologies to protect the region’s vital water infrastructure.
The show-and-tell included a 360-degree imaging system Coghill and his team recently developed to capture up-close views of the interior of pipelines too steep for crews to enter safely. Three-dimensional, virtual reality goggles were available for visitors to experience views recorded by the new imaging system.
A week earlier, the Water Authority hosted a technological show-and-tell for businesses and others interested in advancing the tools necessary to maintain and operate major water delivery systems. The outreach efforts were part of the agency’s expanding initiative to identify new technologies – or new uses for existing technology – to benefit the region’s water ratepayers.
Besides developing its own advanced tools, the Water Authority recently launched an online forum to solicit additional innovative concepts from entrepreneurs and members of the public.
One of the key areas in which the Water Authority has embraced innovation is maintenance of its large-scale pipeline system. Inspections with advanced technologies typically are conducted after the mid-point of a pipe’s projected lifespan, meaning some 60 miles of reinforced concrete pipe will need to be inspected over the next nine years. Visual inspections occur every 10 to 15 years.
Some of the advanced technology used in the asset management program was pioneered by the oil and gas industry, with the Water Authority and other agencies adapting and improving it for use in the water world.
“The Water Authority really is in a leadership role in trying new technologies for cost savings and efficiency, and some of these have been brought to us by private sector,” Water Authority General Manager Maureen Stapleton said during the August showcase. “However, a lot of what has been on show has been developed by our own staff…. I can’t tell you how talented our staff is in this area.”
Added Stapleton: “A lot of this can be scaled down to retail agency size, so it can be transferred to member agencies and so those agencies can make repairs without pulling pipes out and disrupting communities.”
The Water News Network is San Diego County’s source for water news and information.
