Impact of Dredging on the Water Quality of Igbedi Creek, Upper Nun River, Niger Delta, Nigeria

Abstract

The impact of dredging on water quality of Igbedi Creek, upper Nun River, Niger Delta was investigated from June 2009 to May 2011. Two locations-Ogobiri (Dredged) and Agoro-Gbene (Un-dredged) were studied. Two locations-Ogobiri (Dredged Location) and Agoro-Gbene (Un-dredged Location) were studied. For the purpose of this study, the selected dredged and non-dredged sites were divided into stations: Ogobiri-OGO 1 DA=Dredged Area, OGO I&2 DS=Downstream, OGO 1&2 US=Upstream; Agoro-gbene-AGO 1 DS=Downstream, AGO 1 MD=Midstream, AGO 1 US=Upstream. The data revealed significant spatial differences (P<0.05) between the locations in all the water quality parameters measured except for DO, Temp. and pH. There were significant temporal variations as well between the locations in the following parameters: Temperature, Turbidity, Conductivity, N0 3-, NO 2-, S0 4 2-, and BOD 5. The results further showed high increase in values for Turbidity and NO 2-in the station immediately downstream of the dredged area but steadily declined downstream. These results are clear indications that dredging significantly affected the water quality of the creek.