Bisan Seto Fairway

North route: width / 700 to 1,000 m, depth－19 m
South route: width / 700 to 1,000 m, depth－13 m
South-north route: width / 850 m, depth－13 m
Mizushima branch route: width / 700 m, depth－17 m

Bisan Seto Fairway, located on a narrow fairway of the narrowest part of approx 3 km connecting Harima Nada with Hiuchi Nada, serves as the only one trunk seaway connecting islands east to west and vice versa in Seto Inland Sea. Seafaring ships became bigger, and the number of vessels increased since the latter half of the 1955s in the course of industrial siting along the coasts of Seto Inland Sea, and as the port facilities were consolidated.
In those days, however, large number of big and small islands were located along the Bisan Seto Fairway, with sunken rocks spotted, extremely snaking seaway with narrow width and complicated tidal streams, all of which caused ship wrecks frequently.
So, a seaway was constructed as a nationally controlled project from 1963, and thereafter, the area of depth decreased by burial phenomenon was designated as a seaway to be developed and maintained. Seaways are so measured, maintained and dredged in the maintenance control.
The scope almost the same as in Maritime Traffic Safety Act was designated as a seaway to be developed and maintained in December 2009.