Effective use of space inside tubes (optical fiber)

Sewage pipes are widely spread throughout the city and are said to be relatively resistant to earthquakes. Therefore, the construction of an optical fiber network that utilizes the space inside the sewer pipe is attracting attention. This is because no one could be installed in the sewer pipe until now, due to the revision of the Sewerage Law in June 1996.

In Yokohama City, the space inside the sewer pipe plays an important role as a valuable information infrastructure in the city, so from April 1, 1999, first-class electrocommunication companies etc. Installation of optical fibers is now possible.

• Outline of use of lower Water Works Bureau Darkness

Currently, Yokohama City uses NTT's dedicated line to monitor and control the pumping station from the water reclamation center. We are working on the maintenance.

In this optical fiber communication network, we aim to improve the reliability of remote monitoring control and control by transmitting high-quality information such as voice and images, and speeding up transmission speed.

In addition, the optical fiber communication network, we plan to network sewerage facilities, build a comprehensive information system, and plan stable operation and efficiency of sewerage business.

Networking pumping stations (24 operating locations, 3 planned), water recycling centers (11 locations), sludge recycling centers (2 locations), central information centers (future plans), etc. (total length 132km) .

At the end of FY2008, the laying length of the optical fiber in the sewer pipe is 97km.

Yokohama City Optical Fiber Cable Laying Plan (PDF: 1,092KB)