Effect of Permeable Structure on Coastal Sediment Transport in Demak Regency, Central Java, Indonesia Model by Using Delft3D Software

Abstract

Coastal area in Indonesia are places that has a variety of function both economic, culture and social. As time goes by, coastal areas sometimes damaged because of human activities. Declining coastline that caused by erosion is one kind of problems that might be occurs in this area.Coastal area in Timbulsloko is the example of coastal area in Indonesia that’s experiencing declining coastline. One of the attempts to resolve this problem is by constructing permeable structure based on Building with Nature concept. One of the methods to find out whether it’s effective or not is by using software modelling to model sedimentation process in this area. By using Delft3D software, there are three model scenario used to model the sedimentation process. the first scenario was made to model sediment transport in the area itself. The second and third scenario were made to model sediment transport in the area with addition of existing permeable structure design. From the results of the models, the first scenario result shows the area is generally eroded. Furthermore, the placement of permeable structure that is simulated in the second and third model was resulting the increasing sedimentation process around the structure. The sedimentaion process around the structures in the third scenario occurs with sedimentation rate around 0.15 – 0.7 m/year. So, the model shows that the permeable structure itself can be used to protect the coastal area from eroding dan helps the recovery of coastal area.