US Census 2000 Tract Geography modified to conform with SFGIS Library Geography (Streets, Lakes, et al). Water areas have been clipped from this layer. Please refer to the Federal Census for the latest data, these boundaries provided as a convenience.

A. SUMMARY
This dataset is derived from parcels and several other overlay administrative boundaries (listed below). The dataset was developed by DataSF as a convenience for matching parcels to districts where appropriate. This can be simpler than running a geospatial process every time you want to join parcels to a boundary. The districts provided here run along streets and are non-overlapping so that the parcels will be contained within a single district.

The boundaries included are:
1. Analysis Neighborhoods
2. Supervisor Districts
3. Police Districts
4. Planning Districts

B. HOW THE DATASET IS CREATED
A script runs daily that overlays parcels with each of the boundaries to produce the composite dataset.

C. UPDATE PROCESS
Updated daily by a script based on the upstream parcels dataset which is also updated daily.

D. HOW TO USE THIS DATASET
You can use this dataset to match to administrative districts provided here to datasets that contain a parcel number. This can be a simpler process than running these joins spatially.

In short, we pre-process the spatial overlays to make joins simpler and more performant.

Official parcel boundaries pending recorded Covenants, Conditions & Restrictions (CC&R) maintained by San Francisco Public Works