Parcel-based Spatial Evaluation of Actual Land-use Non-conformity with Green Open Space Zoning in the Detailed Spatial Plan of Medan Selayang, Indonesia

Abstract

Urban development can create a measurable gap between spatial plans and actual land use, particularly where Green Open Space (Ruang Terbuka Hijau/RTH) zoning overlaps certified land parcels. This study evaluates the conformity of actual land use with RTH zoning in the Detailed Spatial Plan (Rencana Detail Tata Ruang/RDTR) of Medan Selayang District, Medan City, Indonesia. An evaluative-spatial design was applied, positioning the RDTR as the normative reference and certified land parcels as the legal-spatial units of analysis. The dataset comprised certified parcel maps, RTH zoning maps, base maps, actual land-use interpretation, field documentation and verification notes. Geographic Information System (GIS) overlay was used to identify parcels located within, or intersecting, RTH zones. Each parcel was then classified as conforming, partially conforming or non-conforming according to its observed use and spatial relationship with the RTH designation. The analysis of 200 certified parcels showed that 165 parcels (82.5%) were conforming, 17 parcels (8.5%) were partially conforming and 18 parcels (9.0%) were non-conforming. Non-conformities did not constitute a large contiguous conversion area; instead, they appeared as micro-spatial cases on specific parcels, particularly near road networks, developing urban areas and RTH zoning boundaries or intersections. The identified forms included parking areas, residential use, shop houses, boarding houses, service activities, permanent or semi-permanent buildings and mixed land use. The findings indicate that RTH protection requires parcel-based monitoring that integrates RDTR data, cadastral information, actual land use and Spatial Utilisation Suitability (KKPR) or permit data. The study is limited to a cross-sectional evaluation of 200 field-verified parcels and does not reconstruct historical land-use trajectories or determine the legality of individual permits. Accordingly, the results should be interpreted as a planning-control diagnosis rather than a final legal determination for each parcel.