Long-Term Shoreline Dynamics and Their Implications for Coastal Spatial Management

Abstract

Coastal development increasingly takes place in environments where dynamic shoreline processes undermine the permanence of spatial planning and infrastructure. This research investigates long-term shoreline change along the Tanjung Pandan coast, Indonesia, and assesses its implications for coastal management, with Tanjung Pendam serving as a strategic urban waterfront. A quantitative spatial-descriptive methodology, combined with planning interpretation, was employed using multi-temporal shoreline data from 2000, 2013, and 2025. Abrasion and accretion were spatially delineated and proportionally quantified, while the Integrated City Planning framework was used to analyze coastal-management conditions and planning trajectories. Results indicate that abrasion constitutes 91.86% of the total mapped shoreline-change area, whereas accretion accounts for only 8.14%, revealing a significant imbalance in coastal transformation. At Tanjung Pendam, shoreline dynamics coincide with tidal flooding and spatially variable coastal protection, underscoring a gap between coastal mobility and relatively static planning decisions. The findings do not directly attribute observed shoreline change to sea-level rise but highlight its significance as a future adaptation factor. This research demonstrates that historical shoreline data can serve as a practical foundation for adaptive coastal spatial management by enhancing the integration of shoreline monitoring, spatial planning, and differentiated coastal-management strategies.