Import City of Santa Clara buildings

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In 2017, Mapbox’s data team digitized 32,443 buildings within the Santa Clara city limits based on Bing and Mapbox aerial imagery and imported them into OSM. These manually digitized buildings are of high quality, but the available imagery was quite old, from 2013 or earlier: mapbox/mapping#141 (comment). Since they didn’t come from an official dataset, they lack attributes like addresses and heights that have become the norm elsewhere in Santa Clara County.

The City of Santa Clara has made a building layer from 2015 available under the Public Domain Dedication and License. This data is old but still a couple years newer than what got digitized. It also contains elevations (ele), heights (height), and eave heights (roof:height). We can either update the geometries based on the dataset or enrich the existing geometries with these attributes.

The City also has an address point layer (including subaddresses) from last year we should apply to the buildings at the same time. The land parcel and air parcel layers would make it easier to join the address points to the building polygons.

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These buildings could also go into OpenHistoricalMap at the same time. The City’s MapSantaClara application uses a more detailed land parcel layer under the hood that includes a YEARBUILT attribute equivalent to start_date.

The terms of use mentioning the PDDL apply to the City’s Enterprise GIS Public Portal, not MapSantaClara. However, MapSantaClara contains this language confirming that the data would be in the public domain under California public records law:

Parcel lines and building footprints are not legal representations. The data used in this map is generated by the City and County of Santa Clara, and may contain errors. For the latest assessor's office information, please refer to the County of Santa Clara's Assessor's Office. For the latest Flood Zone information, please reference the FEMA official site.

[1ec5]

Overture Maps resorted to backfilling Santa Clara’s building heights from 3DEP because we haven’t imported this dataset yet. I think this dataset would be a significant improvement over that backfill. I don’t know how 3DEP compares to the LiDAR scan Santa Clara did in terms of accuracy, but the Santa Clara dataset has additional detail about eave heights.