The use of solid-void analysis in evaluating the effectiveness of zoning plan implementation: The case of Kemeraltı historic city center (İzmir)

Historic city centers (HCC) are important urban areas that host a rich cultural and architectural heritage, carrying the traces of the past into the present. These areas, often the earliest settlements of cities, are notable for their narrow streets, squares, and distinctive architectural structures. As historic city centers undergo urban transformation and modernization, the need to preserve and ensure sustainability has intensified. These centers, housing cultural heritage, are often enriched with cultural spaces such as museums, historical monuments, and art galleries. With these features, historic city centers play a crucial role in preserving the identity of cities and maintaining historical consciousness. However, rapid urbanization and excessive population growth, particularly since the 1950s, have negatively impacted historic city centers through new zoning plans. During this period, historic city centers transformed more rapidly than other urban areas, emerging as zones requiring protection. Many cities in Turkey play a key role in regional and urban planning due to their historic city centers. Nevertheless, these areas risk losing their architectural uniqueness and cultural fabric without preservation. Zoning plans are essential tools guiding a city's physical and social development. In historic city centers, zoning plans are specifically designed to preserve cultural and aesthetic values. However, in Turkey, various issues exist regarding the feasibility and monitoring of zoning plans for these historic areas. The sustainability of these centers within the globalization process is directly tied to the effective implementation of such plans. Therefore, the preservation and sustainability of historic city centers should be evaluated through the lens of zoning plan feasibility and effectiveness. In this context, due to the increasing effects of urbanization leading to physical and social deterioration and the ongoing experience of preparing and approving zoning plans, the İzmir Historic City Center, Kemeraltı, has been selected as the case study for this thesis. The Kemeraltı Historic City Center is an example that has played a guiding role in shaping the city throughout history. In this study, the building density and distribution of open spaces in the Kemeraltı HCC were examined using the void-space analysis method, and the spatial usage efficiency of zoning plans was evaluated based on their implementation rates. This research aims to determine the implementation levels of conservation-based zoning plans in Kemeraltı and evaluate the effectiveness of these implementations. Additionally, the study seeks to develop sustainable conservation and planning strategies for other city centers with similar characteristics. Using the İzmir Kemeraltı case as a reference, the goal is to identify areas requiring intervention to ensure the preservation and sustainability of historic city centers. The research investigates reasons behind the failure to implement zoning plans, the increasing frequency of planning processes, and the differentiation in the exercise of authority, aiming to contribute to the preservation of the city's historical core areas and the sustainability of their identity. This thesis provides a comparative analysis of the implementation levels of zoning plans for the İzmir Kemeraltı Historic City Center from 1984, 2005, and 2023. Based on these analyses, recommendations are made for future planning and preservation strategies for historic city centers. This study is considered a vital resource that will contribute to developing sustainable conservation strategies for similar historic city centers. Based on the results of the void-space analyses, the fabric of the Kemeraltı Historic City Center from 1984 was established. Although the physical structure experienced changes in 2005 and more recently, it has generally persisted without significant deterioration. However, by 2024, conservation-based zoning plans have been made for Kemeraltı, but these plans have not been effectively implemented during the application phase.