Port of Santos, which is located in southeastern Brazilian coast, is one of the most important ports of Latin America. Its hinterland is composed by several Brazilian states including São Paulo, Minas Gerais, Mato Grosso, Mato Grosso do Sul, Goiás and Distrito Federal, concentrating more than 60% of Brazilian gross product (CODESP, 2017).
Currently, Port of Santos navigation channel is 15 m deep, and CODESP (São Paulo State Docks Company) plans to reach 17 m deep. This deepening dredging would allow the traffic of Post Panamax and New Panamax vessels in Port of Santos. However, this depth increment would increase siltation rate along navigation channel, requiring larger maintenance dredging volume (GIRELI et al., 2012).
In order to reduce the dredged volume, alternative depth maintenance solutions may be simulated. Thus, this paper compares the scouring efficiency of several jetties that had been proposed for Santos by other authors. Five jetties were retrieved from INPH report (REIS, 1978), and one from the paper “Impact of climate changes on the Santos Harbor” (ALFREDINI et al., 2013).
The different jetties are simulated using hydrodynamic numerical modelling (software Mike 21 FM – Danish Hydraulic Institute), and the evaluation of each jetty’s efficiency consists of comparing currents velocity and direction maps along Port of Santos navigation channel during ebb and flood with the scenario without jetty. The hydrodynamic model is calibrated and validated using five tide gauge stations data and eight flow station measurements along Santos estuary.
The results analysis will consist of comparing and subtracting the currents velocity and direction maps of each scenario with the scenario without jetty. This approach allows identifying the areas with velocity variation and the impact on currents direction in Santos Bay.
Probably, structures with two jetties will be more efficient to scour Port of Santos navigation channel, because the jetties walls would narrow the flow, and increase currents velocity. Moreover, Santos is a touristic city too; the jetties geometry will influence the pattern of currents direction in Santos Bay, where residual currents are responsible for sediment transport along Santos littoral. Therefore, the most suitable alternative must seek balance between Port of Santos channel depth maintenance with minimum impact on adjacent beaches sediment budget.
REFERENCES
ALFREDINI, P.; PEZZOLI, A.; FOURNIER, C.P.; ARASAKI, E. 2013. Impact of climate changes on the Santos Harbor, São Paulo State (Brazil). The International Journal on Marine Navigation and Safety of Sea Transportation, v.7, n.4, p. 609-617, dez. 2013.
CODESP. Porto de Santos: Área de Influência Comercial. Disponível em: . Acesso em: jul. 2017
GIRELI, T. Z.; VENDRAME, R.F. “Aprofundamento do porto de Santos: uma análise crítica”, RBRH – Revista Brasileira de Recursos Hídricos, v. 17, n.3,p.49-59, jul/set 2012.
REIS, L.B.F. Estudo em modelo reduzido de fundo móvel do Porto de Santos. Apresentado no primeiro ciclo de palestras de engenharia costeira. Rio Janeiro, Brasil, 1978.