Kansas/Riley County

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County GIS Department

User ToeBee has made contact with the Riley county GIS department. They are happy to share data with OSM. The only restriction they put on data is that the name and address in parcel data can't be used for marketing. Since OSM has no interest in owner names, this is not a problem. In order to gain access you have to fill out a form and then they give you access to an FTP server with shapefiles on it.


Imports

Several imports of Riley county data are planned. Specific technical details of each import are documented in the ogr2osm translation file. Changesets will be tagged with these tags:

County and City Boundaries

This will only be a geometry update of existing boundaries. The existing boundaries are from older TIGER data. The county data is much higher quality and recent. This does mean it is over-noded in some parts. Simplification using JOSM's way simplification feature with a max error of 2 meters. The results can be inspected in the following files:
county border
city borders
The ways need to be appropriately split up and integrated into existing relations.

Parks

The "parks" shapefile contains outlines of federal, state county and city parks in the county. It has information about who operates the park, contact phone numbers and in some cases an address. Some of the parks in the city of Manhattan are already mapped and the information will need to be manually conflated. Some of the borders are also a little odd with areas being split up along some roads and such. To bring the data into line with normal OSM mapping procedures, some of these areas will be merged, simplified and modified based on the high quality aerial imagery also available from the county GIS department. An ogr2osm translation file is available on github. The raw post-conversion file is available here.

Churches

The "churches" shapefile contains points for places of worship. It includes address and phone number information. Some churches are already mapped and some were imported from GNIS so manual conflation is required. Where possible, the points should be turned into building outlines. I am hoping to distribute this import among several local mappers to help get them involved. So each user would only add maybe a dozen churches. With the small number of objects and manual work of tracing building outlines, no dedicated import accounts will be used. An ogr2osm translation file is avilable on github. The raw post-conversion file is available here

Addresses

Approximately 20,000 addresses are available for the entire county. The data is not entirely homogeneous. It looks like it was pieced together from city and county data. But all of it is very accurate with nodes being placed near the center of building footprints. An ogr2osm translation file is avilable on github. The initial post-conversion file is available here. Manual processing was performed to fix some problems and deal with some odd data including apartments and mobile home parks. The results can be seen in this file.

Further processing has taken place to conflate the data with existing data in OSM. This step has been performed with the addressmerge script. The script was run with the following parameters:

./addressmerge.py [database options] riley_county_addresses_processed.osm riley_county_addresses_merged_new.osm --osc riley_county_addresses_merged_change.osm --nocity 50 --building 2 --buffer 2 -w rl.wkt

This script produces two output files. One file contains changes to existing objects in OSM. This includes merging address data onto building outlines where appropriate and updates to existing address points to add missing city and postcode information. The other file contains new points that will be created. The two files can be opened in JOSM for preview and can be found here: changes and additions. JOSM will prompt you to upload the change file when you go to delete it. Please don't! :)