Santa Cruz County, California/Archive

Landuse Archive

In late 2009, user:srmixter (nmixter) imported official landuse=* zones from the Santa Cruz County GIS (SCCGIS) site. (But not without significant problems!)

The purpose of the SCCGIS landuse=* import was to add official zones for residential, industrial, commercial, parks, farms and forests. The import included (multi)polygons with tags of landuse=public_facility and landuse=special_use, which do not render. These were improved after the import was completed. As they don't display, we added supplemental tags (keeping original tags) based on observation and relevant to something rendered. For example, often a landuse=public_facility polygon can be seen via aerial imagery to be a water tower or sewage treatment facility, so we changed to landuse=industrial. Thus, we hewed to keeping the original data, as we avoided straying towards "coding for the renderers."

Imports are complete for Santa Cruz County. Thanks for your patience. I thought there should have been more zones loaded, but I checked with the shapefile, and it looks like they are all there. Unfortunately I had some problems with the script crashing so there may be some repeated areas and extra nodes. I'll go ahead and continue cleaning them up. Validator in JOSM usually does a good job of deleting the empty nodes. Feel free to adjust any of the layers so they better match the Yahoo/Bing imagery or are not overlapping. The import had two tags for landuse=*: public_facility and and special_use. These are obviously not rendered in OSM. So if you know a better use, feel free to add them. We prefer to keep these areas in OSM if possible. The project is all about the data not necessarily the rendering. I still have a lot of work to do to clean up the imports. Thanks again for your help and patience. - nmixter

Due to the upload script crashing, results occurred in two parts/versions. Unfortunately, there remained broken multipolygon remnants from these uploads, so JOSM's Validator reported multipolygon relations missing their outer member(s) and extra nodes to delete. We had hoped to establish a tag called something like upload_version=1, 2... (monotonically increasing integers) but didn't do so. However, a (multi)polygon WITH Zoning=* (which might have been tagged upload_version=2) is later than an otherwise-identical one WITHOUT Zoning=* (which might have been tagged upload_version=1). Likewise, Atribution=* was uppercased and misspelled in the first upload, but lowercased attribution=* in the second upload. As user:srmixter considers his version 1 & 2 uploads to be complete (see above paragraph), comprehensive work to clean them up (broken multipolygons and duplicate nodes, not the casing and spelling) was completed on the part of user:stevea in 2014: see "landuse version 3" below.

user:stevea took a more render-positive, yet still accurate approach to the landuse=special_use areas of srmixter's versions 1 & 2 landuse=* import which don't render: as Santa Cruz County is largely (over 2/3) wooded with redwood and mixed conifer/deciduous, landuse=special_use areas which are also completely or largely wooded (as viewed by Yahoo/Bing aerial/satellite imaging) were additionally tagged natural=wood. This allowed them to accurately render where they otherwise wouldn't. Some of these landuse=special_use areas have a minor amount of grassland/meadow instead of wood, so while these are wholly tagged as natural=wood they also have scattered landuse=meadow (r natural=grassland areas sprinkled over them. Technically this is a "double-overlap" of landuse=* ("special_use," meaningful only from the SCCGIS data upload, and "meadow or grassland" where appropriate), but as "special_use" doesn't render, wood is a natural tag, and landuse=meadow and natural=grassland superimpose over natural=wood, the effect is both accurate and visually pleasing. In some cases small details like buildings, man_made=* features (water_tower, etc.) and highway=track or highway=path are also included on these landuse=special_use parcels. This follows our early consensus of "capturing zoning with landuse=* is a good first step to avoid large blank areas, but when actual on-the-ground data are also known, they correctly supplement simple zoning (landuse=*)." So, active Santa Cruz County editors (should or do) know that having the County zoned with landuse=* from official data is a (renders pleasingly) good first step, but only that. There is much more editing to do which, over time, additionally improves these data with more details of what is actually "on the ground." Please do not confuse landuse with landcover. Note that landuse=residential means ownership of the entire parcel where the owner lives or rents, so reducing these areas to smaller residential areas (e.g. only where a house and appurtenant structures exist) is incorrect. Also, landuse=meadow is more agricultural than what is often conveyed (it will continue to be used where, for example, cattle can be seen to be actively grazing in aerial imagery or hay is growing), so a newer (2019 onward) trend is to use natural=grassland appropriately. This is correct as it disallows contradictory tags of wood and grassland to exist on the same polygon simultaneously.

After several years (2009-2013) of effort by user:stevea to untangle user:srmixter's version 1 & 2 landuse=* imports, much cleanup was completed, but there remained messy problems (wrong/confusing multipolygons, duplicate polygons and nodes, misspelled tags...) especially in south county's agricultural lands and in the changing patchwork of parcels that make up Big Basin Redwood State Park, Big Creek Forests and the new San Vicente Redwoods (many thousands of hectares in the northwest county). To remedy this, user:stevea did an "import update" using newer SCCGIS data: specifically, the Zoning shapefile from SCCGIS's Landuse folder dated November 2013. These data ("version 3") contained tags of SHAPE_STAr and SHAPE_STLe instead of SHAPE_area and SHAPE_len, though replacement into OSM of any given version 1 or 2 (multi)polygon happened only as older data needed correction or replacement. These (version 3) data have Attribution=Santa Cruz County GIS (contrasted with versions 1 and 2, above). Zones which inherited Zoning=RA are Residential-Agricultural (a live-on "family farm") and may oscillate between landuse=residential and landuse=farmland, so if you have better knowledge, please improve them! Zoning=CA means "Commercial Agricultural" and are more intensively farmed compared to Zoning=RA, usually excluding a residence. There are also some landuse=orchard or landuse=vineyard polygons superimposed on farmland (multi)polygons as viewed by Bing or Digital Globe imagery (especially Zoning=RA as it implies they be agriculturally developed by the live-on landowner). There are >3000 landuse polygons in the version 3 data, each of which were manually/visually compared to version 1 & 2 data and Bing imagery. As of May 18, 2014, this version 3 Zoning (landuse=*) update was completed.

In 2018, newer (than v3) SCCGIS county data (web site, click Data, Land Use & Planning, scroll to Zoning, 11/2/2018 Spatial Dataset) were asserted as v4. We are now at v5 with the 2/9/2019 Zoning.zip Spatial Dataset. Some v5 data have richer tags than earlier versions. The intention continues to be to "best map" these data to OSM-accurate values of landuse=* where newer/better data exist compared to OSM's data. Tag GENERIC is deleted as superfluous. As requested in this changeset comment dialog, the tags used should be documented, as they can and do change slightly between upload_versions. So, starting with upload_version=5: the BASEDTL and BASENM tags are useful descriptions of how the landuse is legally designated, the BASEZN, FULLZN and Zoning tags are useful zoning abbreviations using a countywide protocol, the OBJECTID tag is helpful for direct comparison of data between upload_versions, and the SHAPESTAre and SHAPESTLen tags are useful geometric devices to accurately capture area and length data (in square feet and feet, respectively) of the polygon. A common value for the Zoning tag is TP for Timber Production, entered as landuse=forest. This is contrasted with natural=wood which are areas not actively logged.

Subsequent updates should use increasing integers (6, 7, 8,...) to denote upload_version=* values of newer objects. Going forward, please continue to associate these with explicit dates matching upload_version=* values in the table on the main page. When updating OSM data please add an explicit upload_version=* tag to all newer uploaded SCCGIS objects and/or changeset comments and if needed, update the table, too (including the data's publsh-date). Please use good judgement updating OSM data with newer versions: map your best. Countywide, there are many badly offset (several meters) polygons from these uploads, it seems largely due to a "drift error" when copying and pasting in JOSM. In central county, user:bdiscoe, in Live Oak user:Hartmut Holzgraefe and many others have their names on these edits; the effort to clean them up continues by user:stevea.