SEDIMENT DYNAMICS IN LAGOS HARBOUR - RECONNAISSANCE ON EFFECTS OF DREDGING
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Keywords

Lagos Harbour
Field measurements
MIKE21 model
Sediment dynamics
Dredging

How to Cite

Vijverberg, T., Reneerkens, M., Winterwerp, H., Scholl, O., & Haruna, Y. (2012). SEDIMENT DYNAMICS IN LAGOS HARBOUR - RECONNAISSANCE ON EFFECTS OF DREDGING. Coastal Engineering Proceedings, 1(33), sediment.75. https://doi.org/10.9753/icce.v33.sediment.75

Abstract

Due to economic growth, Lagos Harbour is expanding. Capital dredging is needed to allow larger vessels to call the port. As harbour siltation is already a problem, increase of maintenance dredging is a worry. In the past no data was available to understand the hydraulics and sediment transport to estimate maintenance dredging volumes. This paper presents the reconnaissance of the sediment dynamics in the harbour, based on field data and MIKE21 model simulations. Measurements of sediment concentration, salinity and flow velocity show that estuarine circulation occurs, transporting sediment from the ocean into the port. However, more upstream in the Commodore channel, at the location where dredging will be carried out, this circulation is small. Model simulations show that at that location, bed shear stresses are large, also after dredging. Therefore, fine sediment can not accumulate in the deepened areas and this will not result in large dredging volumes. Sand transport however can cause sedimentation, as bed forms can migrate. These mechanisms are also observed in initial sand transport simulations, but need to be studied further to fully understand the sediment dynamics in the harbour.
https://doi.org/10.9753/icce.v33.sediment.75
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References

Bakker, S.A. 2009. Uncertainty analysis of the mud infill prediction of the Olokola LNG terminal, MSc Thesis, Delft University of Technology.

Ballendux, V. 2011. On the Morphodynamics of Lagos Harbour: an exploratory study of the tidal system, MSc Thesis, Delft University of Technology.

Bentum, K.M. van. 2012. The Lagos coast - Investigation of the long-term morphological impact of the Eko Atlantic City project, MSc Thesis, Delft University of Technology.

Cares 2010. New oil products jetty in Lagos harbour - Dredging feasibility study. Document ref.

C9344-1556, may 2010.

DEEP 2011. Bathymetric, object detection, hydrodynamic and sediment concentration survey - Oando Jetty project, Lagos. Document number: P2231_SIS_R00.

DHI 2008. Mike 21 flow model FM - Hydrodynamic and transport module, scientific documentation.

Ibe, A.C.; Inegbedion, L.E.; Egberongbe, F.A.O.; Orupabo, S. (1989), Online beach evolution model for Nigerian shoreline: a case study of Victoria bar beach, Lagos. Nkwoji, J. A., Yakub A., Ajani, G. E., Balogun, K. J., Renner, K.O., Igbo, J. K., Ariyo, A. A., Bello, B.

Royal Haskoning 2011. Oando Jetty design conditions, Lagos Nigeria.

Torfs, H. 1995. Erosion of sand/mud mixtures. PhD Thesis, Katholieke Universiteit Leuven.

Winterwerp, J.C., and Van Kesteren, W.G.M. 2004. Introduction to the physics of cohesive sediments in the marine environment. 1st edition. Elsevier.

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