The aim of this paper is to have an approach to the phenomena that take place in the lagoon complex of the Ciénaga Grande de Santa Marta (CGSM), which are related to the behavior of the remaining organochloride pesticides. Besides discussing the depuration processes, precipitation/sedimentation and the damping that are present in this coastal lagoon; with an environmental managing scope. The results analyzed were those obtained from the project called “Monitoring of the environmental conditions and the structural and functional changes of the vegetal communities and fishing resources during the rehabilitation of the CGSM”. The main removal type in the CGSM water system for organochloride compounds in the water column, occurs by precipitation/sedimentation processes, as it is observed in Pajaral and Caño Clarín areas, where a decreasing up to 50% of this toxic compounds is happening, related to the unloaded levels.