Mar 12, 2020

Hitachi Zosen Corporation has recently received an order from Hyogo Prefecture (Governor Toshimi Ido) for the manufacturing and construction of a Seabed-type Movable Flap Gate Type Breakwater, which is the second order of the product in Japan. The facility is installed at Fukura Port, Minami Awaji City.

Hyogo Prefecture is being prepared for the Nankai Trough Earthquake, which is expected to occur in the near future, by promoting the "tsunami disaster prevention plans" in many regions. Minami-Awaji City is an area where fishery and tourism are active. As there are a lot of houses behind Fukura Port where "Naruto whirlpools" sightseeing boats leave and also offers the beautiful sightseeing area which has the "Awaji Ningyo-Za" theater with 500 years of tradition, Hyogo Prefecture is promoting the infrastructure improvement as a priority development area.

The port area is forecasted to have a high tsunami level when the Nankai Trough Earthquake occurs. Therefore, watergates, land locks, and tide embankments are being developed for the purpose of reducing inundation damage assuming evacuation for Level 1 tsunami, and reducing the water level comparable Level 1 tsunami for Level 2 tsunami and reducing inundation damage.

The construction is a watergate installation work to close the opening between the Kemurijima Island and Suzaki tide embankments in Fukura Port area, when a tsunami strides. For that purpose, Seabed-type Movable Flap Gate Type Breakwater is adopted. Hyogo Prefecture, with the priority to ensure a reliable closure in a short time and the safety of operators by automated watergates closing operation at Fukura Port, highly appreciated the features of the facility.

Main Features of the Equipment

1. 1When a tsunami or storm surge occurs, the door automatically and quickly comes up to the water surface by releasing the mooring hook at the top of the gate body.
2. 2Since it is installed on the seabed, it keeps the landscape and does not disturb ships traffic.
3. 3The condition of the gate body can be monitored by grasping the volume of the air inside. In addition, since the door body containing the air always swings, it prevents its fixation.

(Example of Installation: General Roller Gate)(Example of Installation: Seabed-type Movable Flap Gate Type Breakwater)

Our Company's water gate business dates back to 1924, with a history of about 100 years. In the meantime, we have supplied various types of watergates, including Japan's first arch-type watergates (Osaka: Ajigawa Watergate). Seabed-type Movable Flap Gate Type Breakwater is the new type of watergates jointly developed by TOYO CONSTRUCTION CO., LTD (Chiyoda-ku, Tokyo, President Yasuji Takezawa) and Penta-Ocean Construction Co., Ltd. (Bunkyo-ku, Tokyo, President Takuzo Shimizu).

In addition to watergates, we are also engaged in social infrastructure businesses such as bridges, stacks and offshore structures, and we will actively contribute to the development of sustainable and strong country and quality infrastructure.

The outline of this case is as follows.

1. 1Client: Hyogo Prefecture (Governor Toshimi Ido)
2. 2Project name : Fukura Port smoke-island watergate installation work (mechanical construction)
3. 3Door dimensions: pure span 25m, effective height: 11m
4. 4Construction site: Fukura, Minami-Awaji City, Hyogo Prefecture
5. 5Date of completion: April 1, 2020 to March 25, 2022
6. 6Order amount: ¥2.3 billion (excluding tax)