City tries new path to fiber network

San Francisco Department of Telecommunications & Information Services

San Francisco is the first U.S. local government customer for a system developed and commercialized by Vienna, Austria, that uses existing sewer systems to build fiber-optic networks.

The system is marketed in the United States by CableRunner North America LLC, a public/private company partly owned by Vienna's Water and Sewer Department.

The CableRunner system strings fiber-optic cable through a city's sewers as an alternative to ripping up streets to lay cable. In sewers too narrow for people to access, robots navigate the pipes and perform installations.

Development of the technology began in Vienna about 15 years ago. The city was trying to build a fiber-optic network but was limited by expense and congestion, said Ellen Rowley, a CableRunner North America spokeswoman.

"The city saw that this technology could also be used by others, and took an educational point of view in telling cities about it," she said. "But then Vienna found people asking the city to do all of the work for them, and that sparked the idea of CableRunner."

The San Francisco city and county are building a two-mile, fiber-optic pilot project using CableRunner technology that will be the system's U.S. showcase. The project was due to start this month and will connect additional facilities to E-Net, the city-owned, conventional fiber-optic network that links government buildings.

The CableRunner system "helps us to deploy fiber to areas we couldn't get to otherwise," said Heidi Sieck, a spokeswoman for the San Francisco Department of Telecommunications and Information Services.

In addition to a 400-kilometer backbone network in Vienna, CableRunner also has installed in Europe a backbone network in Zagreb, Croatia, and has added an eight-kilometer stretch to the fiber network in Salzburg, Austria.

CableRunner will focus on local government and federal homeland security contracts in the United States, Rowley said.

Robinson is a freelance journalist based in Portland, Ore. He can be reached at

About the Author

Brian Robinson is a freelance writer based in Portland, Ore.


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