Coastal protection system design at the Indonesian Mangrove Center in Pekalongan, Central Java – Indonesia

The Pekalongan area suffered from coastal flooding and heavy coastal erosion due to land subsidence and increasing wave condition in the last decade. Pekalongan government built a land dike in 2018 to protect Pekalongan city from coastal flooding. This study aims to determine a suitable coastal protection system, consisting of hard-structures and mangroves, to solve the erosion problem at the Pekalongan coast, specifically at the future Pekalongan Mangrove Information Centre (PIM). Environmental data, i.e., wind, wave, current, tidal, sediment, and soil data, were obtained by field survey and secondary data collection from open-source data. The selection of the most suitable coastal protection design concepts was performed by comparing several alternatives of structure materials. Coastal protection layout was obtained based on a numerical sediment transport model result using Delft3D software. From environmental data processing and analysis with various design aspects, the top elevation of the coastal protection structure is +4.5 m MSL (Mean Sea Level). The configuration of the mangrove planting media consists of 'guludan' structure technique with dimension 10 m x 5 m x 4 m.