AN OVERVIEW OF STOCHASTIC PROCESS AFFECTING SUSPENDED SEDIMENT PRODUCTION IN ENVIRONMENTAL ENGINEERING; CASE OF NORTHERN GHANA

Abstract

Modelling of environmental processes within a basin is an important aspect of environmental engineering. Since most of these processes are stochastic in nature, the application of a stochastic model for an input-output process like the production level of suspended sediment in a river basin resulting from some amount of rainfall is very important. The problem was therefore to establish a model relating daily rainfall depth with suspended sediment concentration (SSC). The Nasia River Basin was therefore used as a study area as it presents a typical northern savanna situation. The vastness of the river basin, the remote location of the rainguage and the complexity associated with runoff process of SSC informed the model being stochastic in nature. Data which informed important aspect of the study included rainfall and suspended sediment concentration levels in the river channels over a period of 90 days in the year 2007. A black-box type model with model parameters of λ = 0.7117, k= 2.846, y = 0.7404 and α= 0.6098 were identified for the period understudy. The black-box therefore serves as a reasonable model for the process involved in the production of suspended sediment. The stochastic process C has a tendency to revert to a value depending on log S. therefore, the system perturbed from the equilibrium state of equation 13 and equation 15 become Further investigations especially on SSC and rainfall are recommended especially for the study area.