PURPOSE: To raise the resistance to waves of a levee by a method in which levees formed by placing concrete to the top portion of a caisson erected on rubble mound are closely connected with each other to form an integrated levee body.

CONSTITUTION: A seaside levee made of caisson 3, blocks, cellular blocks, underwater concrete, etc., is constructed on the seabed or rubble mound 4 formed on the seabed. Concrete 1 is placed on the caisson, etc., to construct the upright dike or mixed dike of the seaside levee. The in-situ top concretes of the caisson are mutually connected by a connector 2 in the longitudinal direction of the levee so constructed, thereby integrating the levee and strengthening the resistance to waves.