Ten collections describing property, zoning, vacancy, and affordable housing in Philadelphia, mirrored from the City of Philadelphia's ArcGIS services via OpenDataPhilly.
Guidance for AI agents and LLMs working with this collection.
Boundaries of Philadelphia's zoning overlay districts, enacted 15 December 2011 and effective 22 August 2012. 195 polygons.
An overlay adds rules on top of the base district beneath it. A single parcel can sit under several overlays at once, so these polygons deliberately intersect.
Coordinates are EPSG:3857 (Web Mercator) metres. DuckDB reads geometry
natively, so do not wrap it in ST_GeomFromWKB.
overlay_name — the overlay's full name.overlay_symbol — its short symbol, e.g. /CTR (54 polygons), /NCA (14), /NCO (13), /TOC (13). 30 polygons carry the literal string [N/A].type — three values: Overlay District (165 polygons), Supplemental Control (25), and Wissahickon Watershed Impervious Coverage Restriction (5).code_section, code_section_link — the section of the zoning code that created the overlay, and a link to its text.pending, pendingbill, pendingbillurl, sunset_date, sunsetbillnum, sunsetbilllink — pending and expiring legislation, as in zoning_basedistricts.Overlays intersect by design. They are not a partition of the city. Summing Shape__Area across overlays double-counts any ground covered by more than one. Dissolve first if you need total covered area.
21 invalid geometries were repaired during extraction.
30 of 195 rows carry [N/A] as their symbol, a literal string rather than a null.
Every rule applying at one point, base district and overlays together:
Overlays by type:
Named overlays with their code sections: