The Bridge of Kali Keruh Plompong uses caisson foundation. There are two caissons in the
south and two caissons in the north, in which the diameter of each caisson is 3 m with the
wall thickness of 20 cm. The middle of the caisson is filled with cyclop concrete with the
composition of 60% K 175 concrete and 40% split stone. During the construction, there are
things which are not in accordance with the planning because there is a big stone under the
south caisson foundation. Therefore, the caisson height is decreased 1.5 m from the first
planning, from 6 m becomes 4 .5 m. This research aims to find out the magnitude of the
caisson foundation carrying capacity. It uses an observational method to obtain the technical
data of the caisson foundation obtained from the survey to the project location. The research
result shows that the carrying capacity of each foundation in S-1 and S-2 spots are greater
than the vertical load.