Launch of Demonstration Tests for Passive Sensors Aimed at Disaster Mitigation
- First Ever Local Government Demonstration Tests Utilizing Fiber Optics Networks for Passive Disaster Prevention Sensors (Rain Gauges and Water Level Gauges) -

April 4, 2014

NTT Data Chugoku Company
Furukawa Electric Co., Ltd.
Nippon COMSYS Corporation, Chugoku Branch

NTT Data Chugoku Company (President: Kazuhiro Nishimura; Headquarters: Hiroshima City, Hiroshima Prefecture), Furukawa Electric Co., Ltd. (President: Mitsuyoshi Shibata; Headquarters: Chiyoda-ku, Tokyo), and Nippon COMSYS Corporation, Chugoku Branch (Branch General Manager: Hiroshi Watanabe; Chugoku Branch location: Hiroshima City, Hiroshima Prefecture) have jointly launched demonstration tests in Kagamino Town, Okayama Prefecture for passive disaster prevention sensors with the aim of reducing the damage caused by natural disasters.

The demonstration tests are being implemented to build systems capable of carrying out real-time monitoring of conditions during periods of sudden torrential rain, which have become more frequent in recent years, by identifying dangerous locations as quickly as possible and giving rapid and detailed predictions of when dangerous situations will arise.

Background and Aims

In recent years, extensive damage has been caused by sudden and localized torrential rain. There are limits to how much can be done to address this problem using structural measures alone, and there is an urgent need to provide an integrated approach that includes non-structural measures. In order to prevent damage from sudden torrential rain, there is a need to collect real-time information on flooding and rain volumes across a broad area. A need has arisen to identify detailed information in each region using the independent measurements of cities, towns and villages, in addition to information provided by prefectural and central governments.

Progress has been made in research into the implementation of passive systems in weather monitoring apparatus (constructed using fiber-optic sensors with no need for power supplies or expensive transmission apparatus on the sensor), and it has become possible to identify in real time the detailed information needed to make evacuation decisions without being affected by power cuts or weather conditions such as lightening.

Introducing the system will allow fiber-optics installation groups to make effective use of fiber-optics and cut operational costs (there is an extremely low risk of malfunctions because there is no need for electrical apparatus).

As part of the above project, the effectiveness of passive sensor networks will be demonstrated in Kagamino Town, which has a well-developed fiber-optics network. Systems capable of carrying out real-time monitoring will also be demonstrated.


Optical rain gauges and optical water level gauges have been connected to the fiber-optic network developed by Kagamino Town and measurement and monitoring is being carried out by monitoring apparatus at a central facility. The rain gauges provide real-time measurements of rain volumes in limited narrow areas. The water level gauges measure water levels in their installed locations in real time, and will assist in future disaster mitigation activities through investigations and analysis into the relationship with upstream rain volumes.

Passive Sensor Network

Planned Developments after the Demonstration Tests

Once the effectiveness of the system is proved through demonstration tests, we will make proposals to groups currently suffering from major damage from sudden torrential rain and to groups already working on countermeasures, and we will assist them in utilizing the system as part of their disaster mitigation measures.
Moreover, by installing the system, groups with fiber-optics already in place will also be able to make effective use of their fiber-optics networks and reduce their operational costs (there is an extremely low risk of malfunctions because there is no need for electrical apparatus).

Main Roles (in no particular order)

  1. Planning, design, operational support and assessment of the demonstration tests
    NTT Data Chugoku Company
  2. Installation of facilities and laying of fiber-optics
    Nippon COMSYS Corporation, Chugoku Branch
  3. Provision of test apparatus and technological guidance
    Furukawa Electric Co., Ltd.
  4. Assessment
    Kagamino Town Office, Okayama Prefecture