A thesis submitted in partial fulfillment of the requirements for the Degree of Master of Engineering at the Asian Institute of Technology, Bangkok, Thailand.

Thesis (M.Eng.) - Asian Institute of Technology, 1975

Characteristics of the tide and current which control the r ate of sediment transport in the Pak Phanang estuary were studied. Harmonic analysis was used in analyzing the tide and current to obtain their interrelationship in order that the current can be predicted from the tidal record. The current was then correlated to the rate of suspended sediment transport. The tide in this study is the mixed tide with predominant semi-diurnal constituent, M2 , and diurnal constituents, K1 , o1 . These three constituents, M2 , K1 , and o1 are also the main constituents from harmonic analysis of current. The tidal velocity of each day was predicted from 24 hour tidal record of the corresponding day. The rate of sediment transport in the estuary depends on the magnitude of the current velocity and their relationship was found to be an exponential form. The results indicate that, from the known functional relationship of the velocity and the rate of suspended sediment transport, the annual sediment load transport can be estimated.