All appeals are dismissed.

The costs of appeal are assessed against the plaintiffs.

The grounds of appeal are examined.

1. Article 31 of the former Road Act (wholly amended by Act No. 12248, Jan. 14, 2014; hereinafter “former Road Act”) provides that, if road works are required due to any construction other than road works (hereinafter “other construction”) or any act other than road works (hereinafter “other act”), the road management agency may have the implementer of the other construction or the person who has conducted the other act execute the relevant road works. Article 76(1) provides that, in whole or in part, the costs of the road works required due to other construction or other acts may be borne by the person liable to bear the expenses of such other construction or other acts.

In addition, Article 77 (1) (main sentence) of the former Road Act provides that, with respect to the expenses of appurtenant works required due to road works or expenses of appurtenant works required to execute road works, the person liable to bear the expenses of roads under this Act shall bear all or part of the expenses of appurtenant works to the extent that he/she causes such need, except as otherwise stipulated in the permission under Article 38 (Occupation and Use of Roads), and the proviso to Article 42 (3) shall be directly executed with the burden of all or part of the expenses of appurtenant works required due to occupation and use when the road management agency executes road works. Article 77 (2) of the former Road Act provides that Article 76 of the same Act shall apply mutatis mutandis to the expenses of appurtenant works where road works become necessary due to other works or other acts.

In full view of the contents, character, legislative intent, etc. of the above provisions of the former Road Act, in a case where road works are required due to other works or acts, and appurtenant works are again required due to such road works or to execute such road works, Article 77 of the former Road Act.