Measures for aging bridges

Of the 1,722 bridges managed by Road and Highway Bureau (as of April 1, 2024), 1,130 bridges, or approximately 66% of the total, have been constructed intensively over the 30 years from 1960 to 1989, the period from high economic growth to the bubble economy. The percentage of bridges that have been constructed for more than 50 years is expected to be about 33% as of 2024, about 58% as of 2034, 10 years later, and about 82% in 2044, 20 years later. It is expected, and the trend is generally similar to the nationwide situation and aging progresses.

If the so-called post-conservation type maintenance is continued after repairs are broken, these bridges will be renewed all at once, and replacement and large-scale repair work will occur, which is expected to be a major financial burden.

In addition, neglecting proper management, such as leaving damage, in the worst case, the bridge may collapse, threatening the safe and secure life of citizens.

Road and Highway Bureau maintains and manages bridges in line with the Yokohama City Bridge Life Extension Repair Plan.
The Yokohama Bridge Long-Term conservation Renewal Plan (March 2004) defines the following objectives as the objectives of the plan.

1. We plan to extend the service life of bridges and minimize the total cost of bridge management over the long term.
2. 1. mitigating and leveling future large financial burdens
3. As basic management policies for the realization of 1 and 2, we will systematically organize inspection methods, conservation renewal policies, and conservation priorities.