Abstract
Field observation for the salt intrusion in Lamong river in Surabaya, Indonesia has been continued by the teams of Hydraulics in ITS and Toyo University. This research has been done under the cooporative research between STS and Toyo University since 1990. This report is the results of theoretical analysis on the tidal motion in the fish ponds which are connected earch other and also connected to the tidal river. But the fields observations are now proceeding and the data from the fields are not sufficient, so the comparison between the theoritical results and the data from the laboratoly model has been done. In this case two connected fish ponds has been done in experiment and the comparison between the theory is good in the response of amplitude and phase lag.
