Several remotely controlled valves in the Reykjavík water utility's distribution system
Arndís Ósk Ólafsdóttir Arnalds, Head of Water and Sewerage at Veitur, discusses the condition and lifespan of pipes in the city centre and water leaks in the buildings of the University of Iceland in a new educational article.
It took about 75 minutes to stop a leak that caused major damage at the University of Iceland earlier this year. The leak was discovered at the Veitur water control centre when a significant drop in pressure was detected in the cold water distribution system west of Snorrabraut. The leak was about 500 l/s, meaning that around 2,250 tonnes of water flowed out. The leak was traced to construction work in the area, and the water pipe that burst is 60 years old.
But what is the condition of the pipes in the city centre?
Pipes commonly last for 70-100 years “The condition of the pipes in the city centre varies. There are very old pipes, brand new ones, and everything in between. Systematic renewal is underway in the city centre, and the priority is determined by age, failure rate, capacity, pipe material, and the investment plans of the City of Reykjavík and other utilities. The lifespan depends primarily on the pipe material, the age of the pipes, and the workmanship during their installation. The lifespan is measured in decades, and it is common for pipes to last for 70-100 years. The water pipe in Suðurgata was about 60 years old, but it was decided to renew it, along with other pipes in the street, in conjunction with the City of Reykjavík's project to renew the surface, i.e., pavements and more. We try to coordinate excavation with the city whenever possible so that Veitur doesn't have to come and disturb a newly laid surface a few years after the city has renewed it.” Arndís mentions that in such renewal work, it is necessary to pay close attention to operational safety with the current system, the finishing around the pipes, sounding, trenches, and safety during construction.
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Had to be shut off manually
The source of the cold water leak was in a water utility valve chamber south of the main building of the University of Iceland and, as mentioned before, the amount of water was enormous, and it took 75 minutes to stop the leak. Many wondered whether there were no automatic valves that shut off in the event of a sudden pressure drop, or remote-controlled ones from the control centre. “There are over 34,000 valves in the water utility's distribution system in Reykjavík. We have a few remote-controlled valves, but not in this area. When meters in the control centre show a significant pressure drop in the water supply, a specific process is initiated. As the event occurred at night, a specialist had to be woken up to find the likely location of the leak, as well as the people who needed to go to the site. A shut-off plan must be made, the ground valves located—which in this case are on the lawns below the main building of the University of Iceland—and dug out in the frost and dark, as one of them had been turfed over, as can be seen in the picture below, and then shut off manually. For comparison, our colleagues at the Oslo utilities experienced a major leak last week, and it took 4 hours to shut it off,” she mentions. The leak in Oslo was last week and you can read about it here.
Now, further work lies ahead. “When the leak occurred, a section of about 100m still needed to be renewed. The project at Suðurgata is scheduled to be completed this spring. You can see Veitur's projects on the Veitur project map here,” says Arndís.
