Abstract: A finite element method for analysis of pollutant dispersion in shallow water is presented.The analysis is divided into two parts:(1) computation of the velocity flow field and water surface elevation,and (2) computation of the pollutant concentration field from the dispersion model.The method was combined with an adaptive meshing technique to increase the solution accuracy,as well as to reduce the computational time and computer memory.The finite element formulation and the computer programs were validated by several examples that have known solutions.In addition,the capability of the combined method was demonstrated by analyzing pollutant dispersion in Chao Phraya River near the gulf of Thailand.

Key words: shallow water, pollutant dispersion, adaptive meshing technique, finite element method